Kodak DirectView User manual

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{TheoryGuide}{Production}{Carestream Health}{Restricted}

Publication No. TG5258-1

18JAN08

Restricted

THEORY GUIDE

for the

Kodak DirectView CLASSIC/ELITE CR SYSTEM

Service Codes: 5258, 5259

Important

• Qualified service personnel must repair this equipment.

• When performing the procedures outlined in this document, personnel must always

employ safe work practices and wear the appropriate personal protective equipment (e.g., safety eyewear) in accordance with Company Standard Operating Procedures.

H219_0001GC

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PLEASE NOTE The information contained herein is based on the experience and knowledge relating to t he subject

matter gained by Carestream Health, Inc. prior to publication. No patent license is granted by this information.

Carestream Health, Inc. reserves the right to chang e this information withou t notice, and ma kes no

warranty, express or implied, with respect to this infor mation. Carestr eam Health shall not be liable for any loss or damage, including consequ ential o r special damages, resulting fr om any use of this information, even if loss or damage is caused by Carestream Health’s negligence or other fault.

This equipment includes parts and assemblies sensitive to damage from electrostatic discharge. Use caution to prevent damage during all service procedures.

Table of Contents

Description Page

Equipment Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Features and Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Main Subsystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Radiography Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Comparison of Film/Screen and Computed Radiography (CR) . . . . . . . . . . . . 15

Overview of CR Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Exposing the STORAGE PHOSPHOR SCREEN. . . . . . . . . . . . . . . . . . . . . . 19

Stimulating the PHOSPHOR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Changing Light Energy to an Analog Signal . . . . . . . . . . . . . . . . . . . . . . . . 22

Changing Analog Signals to Digital Signals . . . . . . . . . . . . . . . . . . . . . . . . 23

Processing the Digital Image. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Sequence of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Overview of Workflow Using the CLASSIC/ELITE CR SYSTEM . . . . . . . . . . . . 25

Before Loading the CASSETTE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Loading the CASSETTE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Removing the PLATE from the CASSETTE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Scanning the SCREEN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Erasing the SCREEN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Inserting the PLATE back into the CASSETTE SHELL . . . . . . . . . . . . . . . . . . . 31

Removing the CASSETTE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

STORAGE PHOSPHOR CASSETTE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Size and Resolution of SCREENS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Fast Scan / Slow Scan Directions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

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Image Matrix Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Reading the BAR CODE LABEL of the CASSETTE . . . . . . . . . . . . . . . . . . . . . . 40

CASSETTE HANDLING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

CASSETTE Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

EXTRACTION BAR MOTOR AY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

CLAMP MOTOR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

PLATE HANDLING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Optical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

LASER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

GALVO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

COLLECTOR and PHOTOMULTIPLIER TUBE (PMT). . . . . . . . . . . . . . . . . . . . . . 61

Scan/Erase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

PLATE SUPPORT AY - Version 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

PLATE SUPPORT AY - Version 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

LEAD SCREW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

EXTRACTION BAR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

REFERENCE SENSOR S5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

PLATE PRESENT SENSOR S6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

SLOW SCAN MOTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

ENCODER. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

ERASE AY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

LAMP CURRENT SENSORS CS1 - CS5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Imaging Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

Scanning the SCREEN - Slow Scan/Fast Scan. . . . . . . . . . . . . . . . . . . . . . . . . . 81

Obtaining the Image Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

Processing the Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Processing the Image. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Logic and Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Operator Input Compone nts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

MONITOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

LOCAL USER INTERFACE (LUI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

BOARDS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

Distribution of Images to the Network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

Sequence of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

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THEORY GUIDE

Power Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

POWER SUPPLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

Power Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

INTERLOCK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

TRANSFORMER T1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

Logs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

Error and Activity Log . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

Actuation Log . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

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THEORY GUIDE Equipment Description

Section 1: Equipment Description

Features and Functions

The Kodak DirectView CLASSIC/ELITE CR SYSTEM is a LASER SCANNER that reads a latent image made on a STORAGE PHOSPHOR SCREEN during an X-ray exam and provides a digital image. Physicians and radiologists can then view, improve, store and make a print of the image, and send the image across a computer network.

Feature Function

SCANNER for the CLASSIC or ELITE CR SYSTEM

BAR CODE READERS

• Size: 43.8 x 60.3 cm (19.0 x 23.75 in.)

• single CASSETTE load with integrated LOCAL USER INTERFACE

• uses DirectView CR CASSETTES

• ELITE CR SYSTEM provides maximum CASSETTE throughput

capability

• CLASSIC CR SYSTEM provides throughput of approximately 25 - 30%

lower than the ELITE CR SYSTEM

• EXTERNAL BAR CODE READER:

– hand-held READER – used to scan the BAR CODE LABEL on CASSETTES and other

bar codes used for entering data

• INTERNAL BAR CODE READER:

– automatically scans the BAR CODE LABEL on CASSETTES that

are loaded

– provides information about the size, speed, and serial number of

the CASSETTE

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THEORY GUIDE Equipment Description

Feature Function

WORKFLOW and IMAGE VIEWING CONSOLE (WAIV)

MONITOR - options:

• 17 in. FLAT PANEL DISPLAY without TOUCH SCREEN - requires use

of KEYBOARD

• 19 in. FLAT PANEL DISPLAY with TOUCH SCREEN

• allows the operator to touch or click areas displayed on the screen to:

– enter exam and patient information – view and improve images

• allows the FE to do service diagnostics

EXTERNAL PC:

• includes software for:

– acquiring images from the CLASSIC/ELITE CR SYSTEM – processing images – providing communication with external devices and the computer

network

Software Options Available

Furniture Options Available

• available at all times to the FE

• new EVP Plus Software

• Administrative Analysis and Reporting

• Total Quality Tool

• Mammography Option - outside US and Canada

• Software Refresh

• FLOOR STAND

• WALL STAND

• either holds MONITOR, KEYBOARD, MOUSE, and BAR CODE

READER

• FLOOR STAND also holds 10 CASSETTES

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THEORY GUIDE Equipment Description

Feature Function

Kodak DirectView

REMOTE OPERATIONS PANEL (ROP)

A device that is installed on the wall in an area separate from the CLASSIC/ELITE CR SYSTEM, used for viewing images and entering data. The ROP includes:

• computer running Microsoft Windows XP

• TOUCH SCREEN MONITOR - SVGA device with a 1024 x 768 pixel

resolution

• EXTERNAL BAR CODE READER - can read all formats identified for

the hand-held BAR CODE READER on the CLASSIC/ELITE CR SYSTEM

The ROP allows operators to:

• enter patient, exam, and CASSETTE (PEC) data into a CLASSIC/

ELITE CR SYSTEM

• check patient data

• view scanned X-ray images

• send images to other nodes on the network

The PEC data entered through an ROP and sent across the network is associated with the correct image.

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THEORY GUIDE Equipment Description

Feature Function

Configurations • STANDALONE - the CLASSIC/ELITE CR SYSTEM is not connected

for use with other CR SYSTEMS on a network:

– CLASSIC/ELITE CR SYSTEM supports use with a maximum of 10

REMOTE DEVICES

– network connects to WORKSTATIONS for viewing, or reading the

images, and to PRINTERS to obtain hardcopy output

• CAPTURE LINK SYSTEM - uses a CAPTURE LINK SERVER to

support shared use of 2 - 5 CR SYSTEMS on a network

• SIMPLE CAPTURE LINK - software option allows shared use of 2 CR

SYSTEMS on a network without using a CAPTURE LINK SERVER

• In a SIMPLE or CAPTURE LINK SYSTEM:

– CR SYSTEMS configured can be Kodak DirectView CR 825/850/

950/975 SYSTEMS or CLASSIC/ELITE CR SYSTEMS

– up to 20 remote devices can be configured for use – workflow is distributed by allowing patient data, CASSETTE ID

information, CASSETTE scanning, and image review functions to be shared between CR SYSTEMS and remote devices

– CR SYSTEMS and remote devices can only share information and

function together within the same SIMPLE or CAPTURE LINK SYSTEM

– CR SYSTEMS network connect to WORKSTATIONS for viewing or

reading the images and/or to PRINTERS to obtain hardcopy output

Remote devices include:

• REMOTE OPERATION PANELS (ROP)

• Customer provided PC using REMOTE ACCESS SOFTWARE (RAS)

allows the PC to be used:

– as a REMOTE PATIENT DATA ENTRY STATION (RPDES) – for performing REMOTE KEY OPERATOR functions.

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THEORY GUIDE Equipment Description

Feature Function

Network Communications

All CLASSIC/ELITE CR SYSTEMS and ROP devices:

• connect to the 10 Base-T, 100 Base-T, or 1000 Base-T Ethernet

network of the site

• can send information to all networked DICOM digital imaging

equipment that is qualified with the CLASSIC/ELITE CR SYSTEM

• use CATEGORY 5 CABLES to connect to the network

• use a gateway device qualified by Carestream Health to enable access

to the HIS/RIS system. The customer must provide this device

On-site Service • CASTERS allow the CLASSIC/ELITE CR SYSTEM to be moved for

service without leveling

• DATA PLATES and MODIFICATION LABELS are located for easy

access and viewing

• PLUGS and CONNECTORS are identified

• data in the Error and Activity logs can be sorted by field for

troubleshooting, for example, by date and error code number

• FEs can view internal diagnostics, including error codes, component

tests, and tests of the SENSORS from the MONITOR

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THEORY GUIDE Equipment Description

Feature Function

Remote Service • remote access options:

– dedicated MODEM connected to the CLASSIC/ELITE CR SYSTEM – MODEM SERVER provided by the customer

• one point of access to the service functions of all CLASSIC/ELITE CR

SYSTEMS on the customer network from the remote service access connection

• access to all service functions, except running the SCAN/ERASE

subsystem

• remote service:

– installing software – setting up the configuration for the CLASSIC/ELITE CR SYSTEM – retrieving and clearing Error and Activity Logs – retrieving Image Processing Library (IPL) diagnostic images

Note

FEs providing remote service cannot view the information about the patient on images.

THEORY GUIDE Equipment Description

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The following table describes the specifications for the number of CASSETTES per hour:

CLASSIC CR SYSTEM ELITE CR SYSTEM

Size

High Speed and

Reduced Border

Scan Mode

Standard Speed

High Speed and Reduced Border

Scan Mode

Standard Speed

24 x 18 GP 77 77 100 100 24 x 30 GP 58 58 76 76 24 x 18 HR 77 77 101 101 24 x 30 HR 58 58 76 76 24 x 18 EHR-M 60 60 79 79 24 x 18 EHR-M2 60 60 79 79 24 x 30 EHR-M 45 45 58 58 24 x 30 EHR-M2 45 45 58 58 30 x 15 GP 92 92 122 122 35 x 35 GP 77 53 102 71 35 x 43 GP 69 46 90 61 35 x 35 GP+ 53 53 70 70 35 x 43 GP+ 46 46 61 61 35 x 43 LONG-

66 66 87 87 LENGTH CASSETTE

35 x 84 GP LLI 68 68 88 88

Tolerance is ± 5

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THEORY GUIDE Equipment Description

Main Subsystems

To Network

MONITOR

EXTERNAL

BARCODE

READER

EXTERNAL

AC Power

90-264 VAC

H219_7500DC

ERASE LAMPS

VOLTAGE

SELECTION

JUMPERS

MINI - MCB

BOARD

INTERNAL BARCODE

READER

ISOLATION

TRANSFORMER

RS-232

POWER SUPPLY

PS1

SLOW

SCAN

ENCODER

SLOW

SCAN

MOTOR

LASER DIODE

DRIVER

BOARD

A17

LASER

IEB

BOARD

LOCAL

USER

INTERFACE

GALVO

2 PMTS

PMT/DAS

BOARD

COLLECTOR

Hospital Network

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THEORY GUIDE Equipment Description

Subsystem Description See:

CASSETTE • includes:

– STORAGE PHOSPHOR

SCREEN that captures and stores the X-ray

STORAGE PHOSPHOR CASSETTE

image for processing

– CASSETTE SHELL that holds the PLATE

• available in 5 sizes and 3 resolutions (GP, HR,

and EHR)

CASSETTE HANDLING

• allows the operator to load the CASSETTE into

the CLASSIC/ELITE CR SYSTEM

• removes the PLATE from the CASSETTE SHELL

• after scanning, installs the PLATE in the

CASSETTE SHELL

• allows the CASSETTE to be removed from the

CLASSIC/ELITE CR SYSTEM

Optical • controls and moves the laser beam to the

SCREEN

• captures the blue light emitted from the SCREEN

Scan/Erase • moves the PLATE at a uniform speed:

– through the scanning area – to the erase position

• removes the residual image on the SCREEN by

exposing it to maximum light

• inserts the PLATE into the CASSETTE SHELL

again

CASSETTE HANDLING

Optical

Scan/Erase

Imaging • assembles the data from the SCREEN and

changes it to digital format

• processes the image

Imaging Sequence

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THEORY GUIDE Equipment Description

Subsystem Description See:

Logic and Control • processes commands from the operator

• controls the operation of all subsystems

Logic and Control

• sends processed images to the network for

distribution

Pow e r D i s t r ib u ti o n • provides power for all subsystems

• has an INTERLOCK SWITCH that actuates when

the FRONT COVER is removed

Error and Activity Logs

• records logs of errors in the system

• records user actions

Power Distribution

Logs

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THEORY GUIDE Radiography Theory

Section 2: Radiography Theory

Comparison of Film/Screen and Computed Radiography (CR)

FILM/

SCREEN

STORAGE

PHOSPHOR

SCREEN

H194_5012HC

X-RAY latent image TUBE

AERIAL IMAGE

X-RAY TUBE

AERIAL IMAGE

(On Film)

(Storage Phosphor)

FILM PROCESSING

CONVERSIONS

visible image

(On Film)

visible imagelatent image

(CRT)

FINAL VISIBLE

IMAGE

(Film or Viewer)

ENHANCED

PROCESSING

X-rays are used in medical imaging to make an image of given body parts on a surface, which can be read by a Radiologist or other medical personnel. The available systems for capturing these images are:

• Screen/film - captures a projection image on an X-ray film

• Computed Radiography (CR) - captures a digital image

THEORY GUIDE Radiography Theory

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The following phases are necessary to capture and process projection radiographs for both screen/film systems and CR systems:

Phase of Image Capture Description

Phase 1 Making the aerial image

In both screen/film and CR SYSTEMS:

• an X-ray TUBE emits X-rays in the direction of an IMAGE

RECEPTOR

• when the X-rays reach the body of the patient, some are

absorbed by the patient and some are not. The result is an “aerial” image with varying degrees of X-ray power (varying numbers of X-ray PHOTONS)

Phase 2 Capturing the latent image

When the IMAGE RECEPTOR is exposed to the X-rays in the

aerial image, a latent image is captured on the RECEPTOR:

• screen/film systems - image is captured on sensitized

radiographic film

• CR SYSTEMS - image is captured on a STORAGE

PHOSPHOR SCREEN. The X-ray PHOTONS that reach the SCREEN charge the PHOSPHOR, making a latent image on the screen

Phase 3 Capturing, changing, and storing the visible image

The latent image must be changed to a visible image, which

can be read by the Radiologist, moved from one place to

another, and stored for use at another time:

• screen/film systems - radiographic film is processed through

chemicals and the latent image is fixed onto the film

• CR SYSTEMS - the latent image on the STORAGE

PHOSPHOR SCREEN is scanned by a laser beam, which stimulates the charged PHOSPHOR on the SCREEN. Blue light is emitted from the stimulated PHOSPHOR, assembled, and changed into analog electrical signals. The analog image is then changed into digital signals and processed. The digital image is stored and displayed by a computer system and can be routed to other computers and PRINTERS through a network

THEORY GUIDE Radiography Theory

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The following table compares the analog and digital health image capture systems.

Analog Screen/Film Systems Digital CR Systems

Uses “Rare Earth” SCREENS GADOLINIUM OXYSULFIDE or

Uses a BARIUM FLOUROHALIDE STORAGE PHOSPHOR SCREEN.

LANTHANUM OXYBROMIDE. Speed range from 100 - 1000. Phosphor SCREEN types. Use:

• General Purpose (GP) for most general

radiography exams

• High Resolution (HR) for general

radiography extremity exams

• Enhanced High Resolution (EHR) for

mammography exams

Film processing parameters are important

No film processing is necessary. in determining the quality of the image, for example: chemical temperature and timing.

It is hard to obtain the same print quality when copies are necessary because of

The user can print a copy of the digital image

at any time with a consistent level of quality. variations in GENERATORS, PROCESSORS, positions, procedures, and conditions for developing the film.

Overexposing or underexposing an image normally makes it necessary to expose the patient to ionizing radiation again.

Image quality is changed by conditions in the environment, for example temperature or humidity.

The image cannot be viewed in more than one place at a time.

Exposure factors do not normally make it

necessary to expose the patient to ionizing

radiation again.

Image quality is not changed by conditions in

the environment.

CR images can be viewed at more than one

place at the same time, in the same building or

in remote nodes on the network.

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THEORY GUIDE Radiography Theory

Analog Screen/Film Systems Digital CR Systems

• Recording medium - film

• Output medium - film

• Storing medium - film

• Recording medium - STORAGE

PHOSPHOR SCREEN

• Output medium - film, paper, digital display

• Storing medium - digital

Image density and contrast are controlled by kilovolts peak (kvP), milliampere seconds (mA.s), and film type.

Viewing quality can only be improved by increasing the brightness of the LAMP that illuminates the film.

The quality of films that are not exposed correctly cannot be improved.

Density and contrast are controlled by image

processing parameters. kvP, and mA.s continue

to be important image control factors for details

and noise in the digital image.

Digital images can be improved by processing

on a computer to change the density, contrast,

sharpness, and other factors.

Images that were not exposed correctly can be

improved. For example, software parameters

can improve image density and contrast.

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THEORY GUIDE Radiography Theory

Overview of CR Technology

Operations

The following operations are necessary to capture the latent image in the STORAGE PHOSPHOR SCREEN and change it to a digital image that can be viewed on a computer screen and sent to a PRINTER.

• Exposing the STORAGE PHOSPHOR SCREEN

• Stimulating the PHOSPHOR

• Changing Light Energy to an Analog Signal

• Changing Analog Signals to Digital Signals

• Processing the Digital Image

Exposing the STORAGE PHOSPHOR SCREEN

X-RAY TUBE

H194_5033BC

aerial

image

STORAGE PHOSPHOR SCREEN

Charged storage phosphors proportional to X-ray energy

absorbed by screen.

latent

image

Lighter values indicate that more x-rays were absorbed by the SCREEN - bone tissue

Mid-range values indicate that fewer x-rays were absorbed by the SCREEN - soft tissue

Darker values indicate that most x-rays were absorbed by the SCREEN - did not pass through the body

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When a STORAGE PHOSPHOR SCREEN is exposed to X-rays:

• special PHOSPHOR on the SCREEN absorbs the radiation in degrees of intensity

determined by the body part and the type of SCREEN:

– soft body tissues absorb a small quantity of radiation - these areas are indicated in the

X-ray image by mid-range values

– bone tissues absorb most of the radiation - these areas are indicated in the X-ray

image by light values

– X-rays that do not hit any obstructions are indicated in the X-ray image by dark values – High Resolution SCREENS absorb less energy than General Purpose SCREENS

• SCREEN has a latent image in the areas that were exposed to the radiation. The quantity

of stored energy or charge on the SCREEN is proportional to the quantity of X-ray energy absorbed by the SCREEN.

Characteristics of the

STORAGE PHOSPHOR

SCREEN

Description

X-ray absorption About 50% of the X-ray energy is released in the form of

fluorescence when the SCREEN is exposed. The X-ray energy remaining makes the latent image on the SCREEN.

Photostimulable luminescence

When the charged PHOSPHOR on the SCREEN is stimulated by light, the PHOSPHOR releases or discharges blue light proportional to the energy the PHOSPHOR has stored.

Fading The latent image fades with time, but it is possible to read data from

the SCREEN for a number of days after scanning.

Residual image After a SCREEN is erased by exposing it to light, it keeps some

charge from the latent image. This charge does not make the SCREEN less effective when it is used again.

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THEORY GUIDE Radiography Theory

Characteristics of the

STORAGE PHOSPHOR

SCREEN

Description

Signal accumulation Signals can accumulate on SCREENS that are not used for more

than 24 hours. Erasing these SCREENS decreases the residual image to the optimum range for using the SCREEN again. Failure to erase these signals can result in artifacts.

Long life The photostimulable luminescent quality of the SCREEN does not

decrease with time. The life of a SCREEN can be decreased by damage to the material.

Stimulating the PHOSPHOR

It is necessary to stimulate the PHOSPHOR in the SCREEN to read the latent image. The following components of the CR SYSTEMS provide this function:

• light source: – exposes the SCREEN with high-intensity light that stimulates the ELECTRONS and

causes the ELECTRONS to be luminescent

– laser beam moves from one side of the SCREEN to the other to expose the image

• GALVO MIRROR: – moves the laser beam across the SCREEN and then back to the start position. At the

same time, the SCREEN moves perpendicular to the scanning direction of the laser beam

– is continually monitored and adjusted to check that the scanning operation is correct

and has a continual speed

• scanning optics: – focuses and shapes the laser beam, keeping the speed and angle of the beam the

same when it moves across the SCREEN

– angle of a laser beam determines the size, shape, and speed of the beam. An

example is the beam of a FLASHLIGHT moving across a flat surface from one edge to the center and to the other edge

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Changing Light Energy to an Analog Signal

The following components of CR SYSTEMS change the light energy in the exposed SCREEN to an analog signal:

• LIGHT COLLECTOR: – provides the collection of the blue light emitted when the SCREEN is stimulated by the

laser beam

– CLASSIC/ELITE CR SYSTEM uses an INTEGRATING CAVITY with MIRRORS to

provide the collection of the blue light

• BLUE FILTER: – does not allow any red light reflected from the SCREEN to reach the LIGHT

DETECTORS

– allows only the blue light to reach the LIGHT DETECTORS

• LIGHT DETECTORS: – are normally PHOTOMULTIPLIER TUBES (PMT) – receive light that enters the COLLECTOR – change the light PHOTONS into ELECTRONS when the PHOTONS enter through a

PHOTOCATHODE. When the ELECTRONS move through the LIGHT DETECTORS, the ELECTRONS increase in number - “gain”

– when more than one LIGHT DETECTOR is used in a system, the system adds and

changes the signals into one output. The output from the added PMTs can include frequencies that are outside of the limits of the system - “noise”. An ANALOG FILTER limits this noise

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Changing Analog Signals to Digital Signals

SAMPLING

image

sample

grid

analog image digital image

(continual values) (discrete values)

pixel code value

(0 - 4095)

image matrix

H194_5014HC

Analog signals are changed to digital signals by sampling the blue light from the STORAGE PHOSPHOR SCREEN and moving it through an ANALOG-TO-DIGITAL CONVERTER to make a digital value for the brightness of each sample.

Sampling is similar to making a photograph of the signal at a given time. The sample has both a horizontal and a vertical value. The size of the sample is defined in the system software for both the horizontal and vertical directions.

• The horizontal value indicates a point in time in the motion of the laser beam across the

SCREEN.

• The vertical value indicates a line on the screen at a right angle to the scanning direction.

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If you locate both the horizontal and the vertical points of the sample on an imaginary matrix, similar to the one in the graphic, the result indicates one pixel in the digital image.

Continual analog input values are changed to output values. In this process, the replacement of small ranges of analog input values with one digital output value occurs. The digital output value indicates one pixel of information on the MONITOR.

The output is a linear digital signal. The CLASSIC/ELITE CR SYSTEM emits a 16-bit digital signal with a total signal range of 65,536 levels. Because it is not possible for the human eye to see this range of separate values, the CLASSIC/ELITE CR SYSTEM changes the 16-bit linear image data to 12-bit log data. This 12-bit log provides data from 0 - 4095 values. These values are used in the CLASSIC/ELITE CR SYSTEM.

Processing the Digital Image

Digital imaging allows users to improve diagnostic images by processing the images. After the digital image is made, the digital data is processed using parameters set up in the software. In the CLASSIC/ELITE CR SYSTEM, this processing occurs in the EXTERNAL PC.

Examples of image processing used for digital images:

• segmentation

• tone scaling

• edge enhancement

• brightness - level

• contrast - window

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THEORY GUIDE Sequence of Operation

Section 3: Sequence of Operation

Overview of Workflow Using the CLASSIC/ELITE CR SYSTEM

1 The Radiology Department receives an exam request. 2 The Radiology Technologist (RT) assembles the patient information. Examples of patient

information are patient name, ID, and accession number.

Note

On the CLASSIC/ELITE CR SYSTEM, you can receive patient information through a DICOMMODALITY WORKLIST PROVIDER.

3 The operator can select network nodes to send the image data. 4 The operator uses a CR CASSETTE to do the exam, capturing the latent image on the

STORAGE PHOSPHOR SCREEN.

5 Using the CLASSIC/ELITE CR SYSTEM or the ROP, the operator enters the CASSETTE

ID Information by scanning the CASSETTE BAR CODE or entering it manually.

6 The operator inserts the exposed CASSETTE into the CLASSIC/ELITE CR SYSTEM.

The system scans the SCREEN, capturing the latent image on the SCREEN and changing it to a digital image. After scanning, the SCREEN is automatically erased and inserted into the CASSETTE SHELL.

7 The CLASSIC/ELITE CR SYSTEM processes the image. If the system is in:

• “Pass-Through Mode” - the image is automatically sent to all network nodes

• “QA Mode” - the operator can process the image and then send it to other network

nodes

8 If necessary, the image can be processed and sent to network nodes again.

THEORY GUIDE Sequence of Operation

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Before Loading the CASSETTE

1 After initializing, the CLASSIC/ELITE CR SYSTEM is ready to receive a CASSETTE for

scanning. The LOCAL USER INTERFACE (LUI) displays:

• Status ICON: green

• name of the system in white text

2 The RT uses a CR CASSETTE to capture the latent image of the body part on the

SCREEN.

Status Summary: Ready to Receive a CASSETTE

• CLAMP BAR is in the open position

• PIVOTING PLUSH is in the open position

• LIGHT SEAL BAR is in the open position

• EXTRACTION BAR is at the home position

• HOOKS are in the down position

Loading the CASSETTE

1 The RT loads the CASSETTE into the INPUT SLOT until the CASSETTE reaches the

CASSETTE ENTRY SENSOR S3.

2 The CASSETTE ENTRY SENSOR S3 detects the CASSETTE, and the SLOW SCAN

MOTOR moves up to lock the TOP CAP of the EXTRACTION BAR.

3 When the CASSETTE is inserted, the INTERNAL BAR CODE READER reads the size,

speed, and serial number of the CASSETTE, then:

• emits a sound

• sends information to the IEB BOARD A2: – “CASSETTE Detected” message – size of the CASSETTE

THEORY GUIDE Sequence of Operation

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4 When the CASSETTE reaches the CASSETTE EXTRACTION SENSOR S4, the CLAMP

MOTOR closes the CLAMP BAR until the CLAMP CLOSED SENSOR S2 is blocked.

Note

If the INTERNAL BAR CODE READER did not read the bar code correctly, the operator must enter the data manually at the LUI. The CLAMP MOTOR will not close the CLAMP until the operator enters the size of the CASSETTE.

5 The MINI-MCB BOARD A1 sends “CASSETTE Detected” message to the IEB BOARD

A2.

6 The IEB BOARD A2 sends a “Scan Request” message to the EXTERNAL PC. 7 The EXTERNAL PC:

• checks that it has the quantity of memory necessary to receive an image

• makes a raw image file to receive the image

• sends a “Scan Request Reply” message to the IEB BOARD A2 with a value of “OK”

8 The IEB BOARD A2 receives the information about the size and speed of the

CASSETTE.

Status Summary: CASSETTE Loaded

• SLOW SCAN is in the up position

• TOP CAP on the EXTRACTION BAR is locked

• CLAMP BAR is closed

• PLATE remains inside the CASSETTE

• HOOKS on the EXTRACTION BAR are not extended

• bar code was read

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THEORY GUIDE Sequence of Operation

Removing the PLATE from the CASSETTE

1 The IEB BOARD A2 sends a message to the MINI-MCB BOARD A1 to load the PLATE. 2 The SLOW SCAN MOTOR moves down to unlock the TOP CAP, and the HOOKS

MOTOR moves to the “HOOKS in Lane” position.

3 The SLOW SCAN MOTOR moves the HOOKS up into the CASSETTE. 4 The HOOKS MOTOR moves the HOOKS to the “Unlatch” position. 5 The PLATE is “Unlatched” from the CASSETTE, and the SLOW SCAN MOTOR moves

the PLATE to the “Star t of Scan” position.

6 The MINI-MCB BOARD A1 sends a message to the IEB BOARD A2 that the PLATE is

loaded.

Note

If any MOTOR does not move correctly, the MINI-MCB BOARD A1 sends an error message to the IEB BOARD A2.

Status Summary: PLATE Fastened

• CLAMP BARS are holding the CASSETTE

• PLATE is fastened to the EXTRACTION BAR

• EXTRACTION BAR is at the “Start of Scan” position with the fastened PLATE

• PIVOTING PLUSH has made a light-tight environment around the CASSETTE

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THEORY GUIDE Sequence of Operation

Scanning the SCREEN

1 The IEB BOARD A2:

• actuates the GALVO

• sends a signal to the MINI-MCB BOARD A1 to start the scan, which star ts the SLOW

SCAN MOTOR

• sends a signal to the EXTERNAL PC that the scan is star ting

2 The EXTERNAL PC displays a PROGRESS BAR on the Scan Status screen. This is a

graphic display only and not a real-time indication of the status of the scanning operation. The LUI also displays a PROGRESS BAR for the scan status.

3 The SLOW SCAN MOTOR rotates, moving the PLATE at a continual speed through the

field of scan in the slow scan direction.

4 The IEB BOARD A2 controls the motion of the laser beam across the SCREEN in the

fast scan direction. The SCREEN is scanned one pixel at a time, one line at a time. See

Scanning the SCREEN - Slow Scan/Fast Scan.

Note

• The fast scan motion is an almost horizontal trace across the SCREEN, from the back of

the SCREEN toward the front. When it reaches the end of a line, it does a fast retrace to start another line. During the scanning, the SCREEN is moving down at a controlled speed to make each fast scan trace one pixel line higher up on the SCREEN than the line before. The result is that the fast scan is in a slightly diagonal trace across the SCREEN.

• The slow scan runs for a determined number of lines in the vertical direction. A set

number of samplings occur for each line. The number is determined by the size of the SCREEN. Both the number of lines and the number of samplings are set up in the calibration for that size of SCREEN.

5 When the end of the scan is reached, the MINI-MCB BOARD A1 sends a status

message to the IEB BOARD A2.

6 The IEB BOARD A2 de-energizes the PMTs, GALVO, and the LASER. 7 The IEB BOARD A2 sends a “Scan End” message to the EXTERNAL PC. The

PROGRESS BAR displays until the image is transferred to the EXTERNAL PC.

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THEORY GUIDE Sequence of Operation

Erasing the SCREEN

1 The IEB BOARD A2 sends an “Erase Plate” command to the MINI-MCB BOARD A1,

which sends a signal to the SLOW SCAN to start the erasing operation.

2 The SLOW SCAN MOTOR actuates and moves the PLATE into the erase position,

determined by the counts of the SLOW SCAN ENCODER.

3 The MINI-MCB BOARD A1 energizes the ERASE LAMPS to illuminate for 2 - 16 seconds

to remove the image from the SCREEN.

Note

The length of time the ERASE LAMPS illuminate is determined by the highest pixel code value of the image that was scanned. If one pair of LAMPS is not operating, the time increases by a factor of 2. If more than one pair of LAMPS is not operating, a message displays on the MONITOR.

4 When the SCREEN is erased, the MINI-MCB BOARD A1 sends the “Erase Done” status

to the IEB BOARD A2.

THEORY GUIDE Sequence of Operation

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Inserting the PLATE back into the CASSETTE SHELL

1 The IEB BOARD A2 issues a command to the MINI-MCB BOARD A1 to:

• return the EXTRACTION BAR to the home position

• insert the PLATE into the CASSETTE

2 The MINI-MCB BOARD A1 reverses the SLOW SCAN MOTOR, which moves the PLATE

up into the open CASSETTE SHELL.

3 The PLATE POSITIONING AY guides the PLATE into the CASSETTE SHELL from the

back side.

4 When the EXTRACTION BAR reaches the home position, the SLOW SCAN MOTOR

stops. At the home position, the ENCODER counts are the saved value.

Status Summary: PLATE Inserted Into the CASSETTE

• SLOW SCAN MOTOR is stopped

• PLATE is inside the CASSETTE

• HOOKS are inside the PLATE

Removing the CASSETTE

1 The IEB BOARD A2 sends an “Eject Cassette” command to the MINI-MCB BOARD A1. 2 The HOOKS MOTOR energizes, and moves the HOOKS to the “Unlatch” position. 3 The CLAMP MOTOR energizes to open the CLAMP BAR until the CLAMP OPEN

SENSOR S1 is blocked.

4 A message on the LUI tells the operator to remove the CASSETTE. 5 The MINI-MCB BOARD A1 sends the “Cassette Ejected” status to the IEB BOARD A2. 6 After the operator removes the CASSETTE, the MINI-MCB BOARD A1 sends a

“Cassette removed” status to the IEB BOARD A2.

Note

The CLASSIC/ELITE CR SYSTEM cannot process another PLATE until the “Cassette Removed” status is received.

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THEORY GUIDE STORAGE PHOSPHOR CASSETTE

Section 4: STORAGE PHOSPHOR CASSETTE

Overview

CASSETTE SHELL

PLATE NOSEPIECE

STORAGE PHOSPHOR SCREEN

PLATE

PROTECTIVE COATING

PHOSPHOR/BINDER

BAR CODE LABEL

H194_5024HCA H194_5024HC

SIDE-1 EXTRUSION

ESTAR Base

LEAD (Pb) BACKSCATTER LAYER

ALUMINIUM (Ai)

HONEYCOMB PANEL

BLACK CELLULOS

ACETATE BACKING

Not in MAMMO

CASSETTES

STORAGE PHOSPHOR CASSETTES have a SCREEN with a layer of PHOSPHOR that is charged by X-ray PHOTONS. STORAGE PHOSPHOR SCREENS can capture a wider range of information within the aerial image than is possible with a screen/film system.

THEORY GUIDE STORAGE PHOSPHOR CASSETTE

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STORAGE PHOSPHOR CASSETTES include:

Component Description

CASSETTE SHELL The SHELL has a CARBON FIBER FRONT and an aluminum BACK.

The SHELL is open on one side for removal of the PLATE. A LATCH on the inside of the PLATE holds it in place inside the SHELL.

PLATE Includes:

• STORAGE PHOSPHOR SCREEN - made of an ESTAR BASE

with a layer of PHOSPHOR PARTICLES suspended in a POLYMER BINDING, a light-absorbing black BACKING, and a LEAD BACKSCATTER LAYER. The PHOSPHOR LAYER has a COATING that extends beyond the edge of the PHOSPHOR to protect the PHOSPHOR from damage.

• BACKING - a rigid aluminum “honeycomb” PANEL that makes

inserting the SCREEN into the CASSETTE SHELL easier.

• 2 hard plastic STRIPS - fastened to the back side of the PLATE to

make the thickness of the PLATE the same as the thickness of the PLATE NOSEPIECE. This uniform thickness allows the PLATE GUIDE ROLLERS to move smoothly on the back of the PLATE.

BAR CODE LABEL Each CASSETTE has a BAR CODE LABEL on the SIDE-1

EXTRUSION. The BAR CODE LABEL identifies the CASSETTE.

SIDE-1 EXTRUSION The edge of the PLATE with the LATCH. The EXTRACTION BAR

HOOKS insert into the LATCH to remove the PLATE from the CASSETTE SHELL.

PLATE NOSEPIECE Plastic edge on the PLATE th at guides the PLATE back into the

CASSETTE SHELL.

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THEORY GUIDE STORAGE PHOSPHOR CASSETTE

Size and Resolution of SCREENS

Size of the SCREEN

15 x 30 cm YES NO NO Kodak DirectView CR 800/825/850/900/950/

35 x 43 cm YES NO NO CR 800/825/850/900/950/975 SYSTEMS

Resolution Compatible With:

GP HR EHR

975 SYSTEMS and CLASSIC/ELITE CR SYSTEMS

and CLASSIC/ELITE CR SYSTEMS

35 x 43 cm - Kodak DirectView CR

YES NO NO CR 800/825/850/900/950/975 SYSTEMS

and CLASSIC/ELITE CR SYSTEMS LONG-LENGTH IMAGING SYSTEM

35 x 35 cm YES NO NO CR 400/800/825/850/900/950/975 SYSTEMS

and CLASSIC/ELITE CR SYSTEMS 24 x 30 cm YES YES --- CR 400/800/825/850/900/950/975 SYSTEMS

and CLASSIC/ELITE CR SYSTEMS

YES CR 850/950/975 SYSTEMS and CLASSIC/

ELITE CR SYSTEMS 24 x 18 cm YES YES --- CR 400/800/825/850/900/950/975 SYSTEMS

and CLASSIC/ELITE CR SYSTEMS

YES CR 850/950/975 SYSTEMS and CLASSIC/

ELITE CR SYSTEMS

THEORY GUIDE STORAGE PHOSPHOR CASSETTE

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The CLASSIC/ELITE CR SYSTEM uses SCREENS with the following resolutions:

Resolution of the

SCREEN

General Purpose (GP)

• thicker PHOSPHOR COATING than the HR SCREEN, making the

image less sharp

Description

• no special exposure procedures are necessary

High Resolution (HR)

• thinner PHOSPHOR COATING than the GP SCREEN, making the

image sharper

• approximately 2 times the X-ray exposure is necessary

Enhanced High Resolution (EHR)

• same PHOSPHOR COATING as the HR SCREEN

• approximately 2 times the X-ray exposure

The light intensity of the exposed GP SCREEN is less than the HR and EHR SCREENS. The CLASSIC/ELITE CR SYSTEM adjusts for the difference in light intensity by adjusting the pixel code values in the image processing.

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THEORY GUIDE STORAGE PHOSPHOR CASSETTE

Fast Scan / Slow Scan Directions

43 cm

Slow Scan

35 cm

30 cm

24 cm

30 cm

15 cm

18 cm

24 cm

Fast Scan

H194_5022BC

The diagram indicates the direction of the 2 scanning actions for each size CASSETTE:

• slow scan - the SCREEN moves vertically from up to down during scanning

• fast scan - the laser beam moves horizontally across the SCREEN at the same time it

moves down

Problems in the slow scan process can cause artifacts in the image. For example, banding artifacts can appear across the SCREEN in the horizontal direction, but the cause of the artifact might be a problem with the vertical slow scan motion of the SCREEN.

THEORY GUIDE STORAGE PHOSPHOR CASSETTE

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Image Matrix Size

The CLASSIC/ELITE CR SYSTEM scans the STORAGE PHOSPHOR SCREENS at the resolutions in the tables below.

Table 1 Standard Resolution CASSETTES (GP) - High Speed Mode

Size of SCREEN

Image Size

Pixels x Lines

30 x 15 cm 2500 x 1250 115 ± 2 4.34 LP/mm 6.3 MB 35 x 43 cm 2048 x 2500 168 ± 2 2.97 LP/mm 10.2 MB 35 x 35 cm 2048 x 2048 168 ± 2 2.97 LP/mm 8.4 MB 24 x 30 cm 2400 x 3020 97 ± 2 5.15 LP/mm 14.5 MB 24 x 18 cm 2392 x 1792 97 ± 2 5.15 LP/mm 8.6 MB 35 x 43 cm LLI 2200 x 2500 168 ± 2 2.97 LP/mm 11.0 MB 35 x 43 cm GP+ 3610 x 4400 97 ± 2 5.15 LP/mm 31.8 MB 35 x 35 cm GP+ 3610 x 3610 97 ± 2 5.15 LP/mm 26.1 MB 35 x 84 cm LLI 2048 x 2600 168 ± 2 2.97 LP/mm 10.7 MB

Table 2 Standard Resolution CASSETTES (GP) - Standard Speed Mode

Pixel Size

in Microns

Spatial Resolution

LP = Line Pairs

File Size

Size of SCREEN

Image Size

Pixels x Lines

Pixel Size

in Microns

Spatial Resolution

LP = Line Pairs

File Size

30 x 15 cm 2500 x 1250 115 ± 2 4.34 LP/mm 6.3 MB 35 x 43 cm 3610 x 4400 97 ± 2 5.15 LP/mm 31.8 MB 35 x 35 cm 3610 x 3610 97 ± 2 5.15 LP/mm 26.1 MB 24 x 30 cm 2400 x 3020 97 ± 2 5.15 LP/mm 14.5 MB 24 x 18 cm 2392 x 1792 97 ± 2 5.15 LP/mm 8.6 MB 35 x 43 cm LLI 2200 x 2500 168 ± 2 2.97 LP/mm 11.0 MB 35 x 43 cm GP+ 3610 x 4400 97 ± 2 5.15 LP/mm 31.8 MB 35 x 35 cm GP+ 3610 x 3610 97 ± 2 5.15 LP/mm 26.1 MB 35 x 84 cm LLI 2048 x 2600 168 ± 2 2.97 LP/mm 10.7 MB

THEORY GUIDE STORAGE PHOSPHOR CASSETTE

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Table 3 Standard Resolution CASSETTES (GP) - Reduced Border Mode

Size of SCREEN

Image Size

Pixels x Lines

Pixel Size

in Microns

Spatial Resolution

LP = Line Pairs

File Size

30 x 15 cm 2500 x 1250 115 ± 2 4.34 LP/mm 6.3 MB 35 x 43 cm 2048 x 2500 171 ± 2 2.97 LP/mm 10.2 MB 35 x 35 cm 2048 x 2048 171 ± 2 2.97 LP/mm 8.4 MB 24 x 30 cm 2400 x 3020 97 ± 2 5.15 LP/mm 14.5 MB 24 x 18 cm 2392 x 1792 97 ± 2 5.15 LP/mm 8.6 MB 35 x 43 cm LLI 2200 x 2500 168 ± 2 2.97 LP/mm 11.0 MB 35 x 43 cm GP+ 3610 x 4400 97 ± 2 5.15 LP/mm 31.8 MB 35 x 35 cm GP+ 3610 x 3610 97 ± 2 5.15 LP/mm 26.1 MB 35 x 84 cm LLI 2048 x 2600 168 ± 2 2.97 LP/mm 10.7 MB

Table 4 High Resolution CASSETTES (HR)

Size of SCREEN

Image Size

Pixels x Lines

Pixel Size

in Microns

Spatial Resolution

LP = Line Pairs

File Size

24 x 18 cm (HR) 2392 x 1792 97 ± 2 5.15 LP/mm 8.6 MB 24 x 30 cm (HR) 2400 x 3020 97 ± 2 5.15 LP/mm 14.5 MB

Table 5 Enhanced High Resolution CASSETTES (EHR-M and EHR-M2)

Size of SCREEN

Image Size

Pixels x Lines

Pixel Size

in Microns

Spatial Resolution

LP = Line Pairs

File Size

24 x 30 cm (EHR) 6000 x 4800 48.5 ± 2 10.3 LP/mm 54.6 MB 24 x 18 cm (EHR) 4784 x 3584 48.5 ± 2 10.3 LP/mm 34.3 MB

THEORY GUIDE STORAGE PHOSPHOR CASSETTE

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For smaller SCREENS, compared to larger SCREENS:

• pixel size is smaller

• spot size of the laser beam and digitizing rate are the same

• scanning speed is slower. To make smaller pixels, the speed of the horizontal motion of

the laser beam will decrease during the fast scan and the transport speed of the SCREEN under the COLLECTOR will decrease during the slow scan. The decrease in pixel size increases the spatial resolution of the image.

The spatial resolution is determined by the following factors:

• scatter of the PHOSPHOR

• spot size and shape of the laser beam

• bandwidth of the electronics

Note

The image file size for the 24 x 30 cm SCREEN is larger than the image file size for the 35 x 35 cm SCREEN because of the higher sampling rate.

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THEORY GUIDE STORAGE PHOSPHOR CASSETTE

Reading the BAR CODE LABEL of the CASSETTE

BAR CODE

H194_5025GCA

H194_5025GC

THEORY GUIDE STORAGE PHOSPHOR CASSETTE

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The BAR CODE LABEL identifies the CASSETTE and provides the size and resolution of the SCREEN. The following table describes the digits in the BAR CODE. Each digit indicates a group of BARS on the bar code.

Digit Value

1 Has the value “9” 2 Resolution:

1 = General Purpose (GP) 2 = High Resolution (HR) 3 = Enhanced High Resolution (EHR)

3 - 4 Size:

01 = 24 x 18 cm 02 = 24 x 30 cm 03 = 35 x 35 cm 04 = 35 x 43 cm 05 = 35 x 43 L 06 = 15 x 30 cm 07 = 24 x 30 cm (HR) 08 = 24 x 18 cm (EHR) 09 = 24 x 30 cm (EHR) 10 = 35 x 35 C 11 = 35 x 43 C

5 - 10 Serial number of the CASSETTE

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THEORY GUIDE CASSETTE HANDLING

Section 5: CASSETTE HANDLING

Overview

CASSETTE

CLAMP MOTOR

EXTRACTION BAR

EXTRACTION BAR MOTOR

H219_7501HCA H219_7501HC

The CASSETTE HANDLING SYSTEM locates the CASSETTE in the correct position in the CLASSIC/ELITE CR SYSTEM, removes the PLATE from the CASSETTE and scans the SCREEN. The CASSETTE HANDLING SYSTEM includes the following systems:

• CASSETTE Load

• EXTRACTION BAR MOTOR AY

• CLAMP MOTOR

• PLATE HANDLING

THEORY GUIDE CASSETTE HANDLING

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Overview of operation:

1. The operator inserts the CASSETTE into the INPUT SLOT of the CLASSIC/ELITE CR

SYSTEM.

2. The SENSORS detect that the CASSETTE is fully inserted into the INPUT SLOT:

• CASSETTE ENTRY SENSOR S3

• CASSETTE EXTRACT SENSOR S4

3. The CLAMP MOTOR closes the CLAMP BAR on the CASSETTE.

4. The EXTRACTION BAR fastens onto the PLATE and moves it down during scanning.

5. After scanning and erasing, the EXTRACTION BAR returns the PLATE to the CASSETTE.

6. The CLAMP MOTOR opens the CLAMP BAR to release the CASSETTE.

7. The CASSETTE is available for the operator to remove.

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THEORY GUIDE CASSETTE HANDLING

CASSETTE Load

MINI-MCB

BOARD

RS-232

IEB

BOARD

INPUT SLOT

CASSETTE ENTRY SENSOR S3

H219_7511HCA

H219_7511HC

The CASSETTE ENTRY SENSOR S3 detects that a CASSETTE is loaded and sends information about the CASSETTE to the MINI-MCB BOARD A1 and the IEB BOARD A2.

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THEORY GUIDE CASSETTE HANDLING

CASSETTE EXTRACTION SENSOR S4

PIVOTING PLUSH

CASSETTE END STOP

CASSETTE ENTRY SENSOR S3

H219_7512HCA

H219_7512HC

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THEORY GUIDE CASSETTE HANDLING

Component Description

INPUT SLOT The operator slides the CASSETTE into the INPUT SLOT. CASSETTE ENTRY

SENSOR S3

The CASSETTE ENTRY SENSOR S3 is continually monitored to detect a CASSETTE. When a CASSETTE is inserted, the light beam of S3 is blocked.

CASSETTE EXTRACT SENSOR S4

The CASSETTE EXTRACT SENSOR S4 detects that the CASSETTE is fully inserted into th e INPUT SLOT.

PIVOTING PLUSH When the CASSETTE is in scan position, the PIVOTING PLUSH

makes a light-tight environment around all sides of the CASSETTE. The PIVOTING PLUSH has FIBERS fastened to BARS on each side of the CASSETTE. To prevent light from reaching the SCREEN when it is removed from the CASSETTE, the PIVOTING PLUSH rotates toward the CASSETTE.

1. The operator inserts a CASSETTE into the INPUT SLOT.

2. When the CASSETTE ENTRY SENSOR S3 is blocked by the CASSETTE, a “Cassette

Detected” message is sent to the MINI-MCB BOARD A1.

3. The MINI-MCB BOARD A1 sends a signal to the INTERNAL BAR CODE READER, which

then reads the BAR CODE LABEL on the CASSETTE.

4. The INTERNAL BAR CODE READER sends the information about the CASSETTE to the

MINI-MCB BOARD A1.

5. The system emits a beep.

6. The MINI-MCB BOARD A1 sends:

• “Cassette Detected” message to the IEB BOARD A2

• CASSETTE ID to the IEB BOARD A2

7. The IEB BOARD A2 sends:

• “Cassette Detected” message to the MINI-MCB BOARD A1

• “Scan Request” message to the EXTERNAL PC

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8. The EXTERNAL PC:

• checks that it has the quantity of memory necessary to receive an image

• makes a raw image file to receive the image

• sends a “Scan Request Reply” message to the IEB BOARD A2 with a value of “OK”

9. The MINI-MCB BOARD A1 sends a signal to the CLAMP MOTOR to rotate the SENSOR

DRIVE PLATE counterclockwise until detected by the CLAMP CLOSED SENSOR S2. The CLAMP BAR and the PIVOTING PLUSH are closed.

10.After scanning, the MINI-MCB BOARD A1 sends a signal to the CLAMP MOTOR to rotate

the SENSOR DRIVE PLATE clockwise until detected by the CLAMP OPEN SENSOR S1. The CLAMP BAR and the PIVOTING PLUSH are opened.

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THEORY GUIDE CASSETTE HANDLING

EXTRACTION BAR MOTOR AY

LIGHT SHIELD

EXTRACTION BAR MOTOR ENCODER

INTERNAL BAR CODE READER

EXTRACTION BAR MOTOR

H219_7517BCA H219_7517BC

DRIVE CRANK

The EXTRACTION BAR MOTOR AY moves the EXTRACTION BAR HOOKS that pull the PLATE from the CASSETTE for scanning the SCREEN.

Component Description

DRIVE CRANK The DRIVE CRANK engages the HOOK PLATE and moves it to the

positions necessary to “latch” and “unlatch” the PLATE from the CASSETTE.

LIGHT SHIELD The LIGHT SHIELD decreases inter nal light reflectance from the ERASE

LAMPS.

EXTRACTION BAR MOTOR ENCODER

The EXTRACTION BAR MOTOR ENCODER sends information about the position of the EXTRACTION BAR MOTOR to the MINI-MCB BOARD A1.

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THEORY GUIDE CASSETTE HANDLING

Component Description

INTERNAL BAR CODE READER

The INTERNAL BAR CODE READER:

• is a component of the EXTRACTION BAR MOTOR AY

• reads the bar code information from the BAR CODE LABEL on the

CASSETTE

• sends the bar code information to the IEB BOARD A2

• sends the bar code information to the MINI-MCB BOARD A1 using

an RS-232 connection

Figure 1 Positions of the EXTRACTION BAR MOTOR

Home Position 1

H219_7518BC

EXTRACTION BAR MOTOR

Position 2

Position 3

The EXTRACTION BAR MOTOR moves the DRIVE CRANK to each of 3 positions:

• Home Position 1 - HOOKS are retracted.

• Position 2 - HOOKS are in position to “latch” the PLATE.

• Position 3 - HOOKS are in position to “unlatch” the PLATE.

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H219_7521BC

CLAMP CLOSED POSITION

CLAMP OPEN POSITION

CLAMP MOTOR M1

DRIVE BELT

CLAMP CLOSED SENSOR S2

SENSOR S1

CLAMP OPEN

DRIVE POST

SENSOR DRIVE PLATE

DRIVE POST

PLATE

DRIVE

SENSOR

SENSOR S2

CLAMP OPEN

SENSOR S1

CLAMP CLOSED

DRIVE BELT

CLAMP MOTOR M1

H219_7521BCA

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THEORY GUIDE CASSETTE HANDLING

CLAMP MOTOR

OPEN

The CLAMP MOTOR M1 energizes to either open or close the CLAMP BAR.

Component Description

CLAMP MOTOR M1The CLAMP MOTOR M1 energizes to rotate the SENSOR DRIVE

PLATE:

• counterclockwise to close the CLAMP BAR

• clockwise to open the CLAMP BAR

CLAMP OPEN SENSOR S1

CLAMP CLOSED SENSOR S2

SENSOR DRIVE PLATE

The CLAMP OPEN SENSOR S1 detects when the CLAMP BAR is fully open.

The CLAMP CLOSED SENSOR S2 detects when the CLAMP BAR is fully closed.

The SENSOR DRIVE PLATE rotates to actuate either :

• CLAMP OPEN SENSOR S1

• CLAMP CLOSED SENSOR S2

THEORY GUIDE CASSETTE HANDLING

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1 The operator inserts the CASSETTE into the INPUT SLOT. 2 The SENSORS detect that the CASSETTE is fully inserted:

• CASSETTE ENTRY SENSOR S3

• CASSETTE EXTRACT SENSOR S4

3 The MINI-MCB BOARD A1 energizes the CLAMP MOTOR M1 to rotate the SENSOR

DRIVE PLATE counterclockwise to close the CLAMP BAR.

4 To open the CLAMP BAR, the MINI-MCB BOARD A1 energizes the CLAMP MOTOR M1

to rotate the SENSOR DRIVE PLATE clockwise.

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THEORY GUIDE CASSETTE HANDLING

PLATE HANDLING

The PLATE HANDLING components remove

CASSETTE

HOOKS

EXTRACTION BAR

Fastening the PLATE

to the EXTRACTION BAR

END STOP

the PLATE from the CASSETTE SHELL and fast en it to t he EXTRACTION BAR.

The EXTRACTION BAR holds the PLATE dur ing the scanning operation, then inserts it back into the CASSETTE SHELL.

CASSETTE

PLATE

SCREEN

EXTRACTION BAR

Pulling the SCREEN

Down for Scanning

H219_7513CCA

H219_7513CC

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THEORY GUIDE Optical

Section 6: Optical

Overview

EXTERNAL

motion

commands

HOSPITAL

NETWORK

LUI

IEB

BOARD

digital

image

data

FOLD MIRROR

F-THETA LENS

PMT/DAS

BOARD

A/D

CONVERTER

PMTs

analog

image data

SCREEN

COLLECTOR

blue light

red

laser

light

H219_7519DCA H219_7519DC

RS-232

GALVO

A17

LASER DIODE

DRIVER BOARD

LASER

MINI-MCB

BOARD

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The OPTICAL subsystem:

• generates the laser beam and provides the deflection of the beam onto the SCREEN

• moves the laser beam across the SCREEN at a controlled rate to release the stored

energy in the PHOSPHOR

• obtains the image by capturing the light that was released and changing it to a digital

format

The OPTICAL subsystem includes the following main components:

• LASER

• GALVO

• COLLECTOR and PHOTOMULTIPLIER TUBE (PMT)

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H219_7514HC

SCREEN

H219_7514HCA

GALVO

F THETA LENS

FOLD MIRROR

F THETA LENS

GALVO

PLATE

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THEORY GUIDE Optical

LASER

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THEORY GUIDE Optical

Component Description

LASER Type 30 mW LASER DIODE DRIVER BOARD that emits a red

beam of high intensity light. The IEB BOARD A2 controls the power of the LASER:

• Threshold” - supplies minimum power when the LASER is

moving to the start of the next line - retrace

• “Scan” - supplies full power to the LASER during scanning

• “Full-on” - used for diagnostics

COLLIMATING OPTICS

MANUAL SAFETY SHUTTER

Provides focus for the light beam to make the spot of light the correct size on the SCREEN.

Has a NEUTRAL DENSITY FILTER that decreases the power of the light emitted by the LASER. When you check the operation of the OPTICAL subsystem, you can change the position of the SHUTTER to make the light from the LASER move through the FILTER. The FILTER decreases the power of the LASER, which prevents damage to the eyes. The graphic on Page 53 indicates the position of the MANUAL SAFETY SHUTTER when it is in the path of the LASER.

During normal operation of the CLASSIC/ELITE CR SYSTEM, the MANUAL SAFETY SHUTTER does not block the path of the LASER.

GALVO Controls the motion of the light beam from the LASER across the

SCREEN in the fast scan direction - horizontal.

F-THETA LENS Changes the light beam from the LASER from a continual angular

position to a continual linear position.

FOLD MIRROR Changes the direction of the light beam from the LASER to align it

in the center of the COLLECTOR.

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THEORY GUIDE Optical

GALVO

GALVO CONTROL

FPGA

IEB BOARD

Clock Signal

Offset and Amplitude

Actual

Position

Signal

Desired Position

Desired Position Signal

Closed Loop

Servo Circuit

Drive Signal

GALVO

A17

LASER DRIVER

DIODE BOARD

GALVO

MIRROR

H219_7502HC

The GALVO moves the laser beam to scan the SCREEN:

• rotates the GALVO MIRROR to cause the laser beam to scan across the SCREEN - fast

scan

• moves to the beginning of the next line on the SCREEN

• scans the next line until the SCREEN is fully scanned

The GALVO uses a feedback system in which the desired position of the GALVO MIRROR is compared to the actual position in the rotation, and corrections are made to keep the GALVO in the correct position on the SCREEN at the correct time. When the GALVO is in the correct position, the laser beam is also in the correct position.

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THEORY GUIDE Optical

Component Description

GALVO Includes:

• MOTOR - rotates the SHAFT

• SHAFT - has a MIRROR at one end to send the laser beam

toward the F-THETA LENS

IEB BOARD A2 Includes a feedback circuit that controls the position of the GALVO

MIRROR. The position of the GALVO MIRROR determines the position of the laser beam. The IEB BOARD A2 uses the following information to define the desired position of the GALVO MIRROR:

• clock signal from the FPGA, which moves the GALVO through the

desired position between the offset and amplitude.

• values for the PLATE size, which were set up during calibration:

– offset - starting point – amplitude - the distance to move across the SCREEN

Information from POSITION SENSORS determine the position of the GALVO SHAFT in the scan - the actual position. The actual position is compared to the desired position and corrections in position are made to provide a smooth motion of the beam.

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Traces in the Operation of the GALVO

POSITION

ACB

TIME

DESIRED-POSITION

TRACE

ACTUAL-POSITION

TRACE

VELOCITY

SCAN

"0" Velocity

The following table describes the positions within the 3 traces.

H219_7503HC

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THEORY GUIDE Optical

Traces of the GALVO Description

Desired position trace

• position A - the FPGA has sent a signal to the GALVO control to

retrace

• between Positions A and B - the system is moving the GALVO

to complete the retrace

• between Positions B and C - the speed of the GALVO is

increasing to operating speed

• position C - the PIXEL CLOCK starts and the PMT /DAS BOARD

A5 starts measuring the pixel data from the SCREEN. The laser beam is at the edge of the SCREEN

• between Positions C and D - the complete line of pixels is

scanned

• position D - the laser beam is at the other edge of the PLATE

and the PIXEL CLOCK stops

Actual position trace • matches the desired position trace during scanning of the

SCREEN

• does not match the desired position trace between Positions A

and B, indicating the time necessary for the GALVO to be stable and start moving across the next line

Velocity trace • GALVO is moving in the scanning direction when the trace is

above the “0 Velocity” line in the diagram

• GALVO is moving in the retrace direction when the trace is below

the “0 Velocity” line

• GALVO is moving at a constant speed during scanning

• the speed of the GALVO increasing to operating speed between

Positions B and C

• the difference between the scanning and retrace speed is larger

than it appears in the diagram

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COLLECTOR and PHOTOMULTIPLIER TUBE (PMT)

The COLLECTOR and the PMTs:

• provide the collection of the blue light emitted from the PHOSPHOR SCREEN

• measure the brightness of the blue light

• change the measurement of brightness to a propor tional electrical signal

analog signal

LIGHT COLLECTOR

PMT

(1 of 2)

red laser light

H194_5009GC

BLUE FILTER

blue light

PHOSPHOR SCREEN

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THEORY GUIDE Optical

Component Description

IEB BOARD A2 Controls the operation of the PMT/DAS BOARD A5 to provide for the

measurement and collection of image data at the correct time:

• sends a signal to the GALVO to rotate the GALVO MIRROR to

move the laser beam in the fast scan direction across the SCREEN

• sends a signal to the PMT/DAS BOARD A5 to measure the

emitted light at controlled times. Each measurement makes a pixel in the completed image.

LIGHT COLLECTOR Provides the collection of the blue light emitted from the SCREEN

and sends it toward the PMTs. The inside surface of the COLLECTOR is reflective.

BLUE FILTER Removes any red laser light reflected from the SCREEN, allowing

only the blue light to reach the PMTs.

PHOTOMULTIPLIER TUBES (PMT)

PMT/DAS BOARD A5

2 LIGHT SENSORS, which emit a current signal corresponding to the light reaching the FACE of the PMT. The PMTs use a high-voltage POWER SOURCE to operate. The voltage of the POWER SOURCE determines the sensitivity of the PMTs.

Changes analog signals from the PMTs to digital format:

• amplifies the signals from the 2 PMTs

• adds the signals from the PMTs

• filters the summed signal

• changes the summed signal to a digital format

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Collection of the Blue Light

ANODE

0 V DC

DYNODE 7

-100 V DC

DYNODE 8

-50 V DC

DYNODE 6

-150 V DC

DYNODE 5

-200 V DC

DYNODE 3

-300 V DC

DYNODE 4

-250 V DC

FOCUSING ELECTRODE

DYNODE 2

-350 V DC

DYNODE 1

-400 V DC

-500 V DC

Path of electrons from PHOTOCATHODE

Blue Light From PLATE /SCREEN

PHOTOCATHODE

-600 V DC

H194_5043HC

When the red light from the LASER reaches the SCREEN, blue light is emitted in random directions. The COLLECTOR captures most of the rays of blue light and provides the deflection of the rays toward the FACE of the PMTs.

Changing the Blue Light to Electrical Current

1 Some of the red light from the LASER that reaches the SCREEN is reflected and enters

the COLLECTOR. A BLUE FILTER between the COLLECTOR and the PMTs rejects most of the red light and allows the blue light to enter. The PMTs receive only the blue light from the SCREEN.

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2 Inside the PMT are a number of components that are connected to varying levels of high

voltage. The circuits on the PMT/DAS BOARD A5 separate the high voltage into a descending series of voltages. These voltages are connected to components in the PMT. In the graphic, examples of voltages are listed.

Note

The HIGH VOLTAGE POWER SUPPLY provides a high negative voltage limited to lower than 2 mA. The PHOTOCATHODE is connected directly to the -600 V source. The FOCUSING ELECTRODE in the PMT is set to -500 V. Next to the FOCUSING ELECTRODE are a series of DYNODES, which are set at decreasing voltages until at the end is an ANODE which is set at 0 V.

3 The PHOTOCATHODE emits an ELECTRON when it is hit by a light PHOTON. Because

the efficiency of the PHOTOCATHODE is less than 100%, the number of ELECTRONS is less than the number of PHOTONS entering the PMT.

4 The negatively charged ELECTRON is influenced by the electrical field between the

PHOTOCATHODE at -600 V and the more positive FOCUSING ELECTRODE at -500 V, pulling the ELECTRON toward the FOCUSING ELECTRODE.

5 When the ELECTRON moves toward the FOCUSING ELECTRODE, it is pulled by the

more positive DYNODE. When the ELECTRON hits the DYNODE surface, it reflects from the surface and emits more ELECTRONS. At each DYNODE, the number of ELECTRONS increases, more electrons are added, and all the ELECTRONS are attracted to the next more positive DYNODE.

6 At the end of the PMT, all the ELECTRONS are attracted to the ANODE, which

assembles the ELECTRONS and sends the ELECTRONS to the PMT/DAS BOARD A5 in a small current signal.

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Operation of the PMT/DAS BOARD A5:

PMT/DAS BOARD

2 CURRENT-TO-VOLTAGE

AMPLIFIERS

2 PMT GAIN CONTROL

D/A CONVERTERS

SUMMING AMPLIFIER

2 - LOW PASS FILTER

300 KHz - 1MHz

300 1mg

16-BIT A/D CONVERTER

16 bit

DATA MULTIPLEXER

blue light

H219_7504HC

ANODE

PMT1

ANODE

PMT1

analog voltage signals

to HIGH VOLTAGE DIVIDERS

HIGH VOLTAGE

POWER SUPPLY

Data

clock

raw image

data

Serial Data

IEB BOARD

PIXEL CLOCK

FPGA

FIFO BUFFER

RAM

EXTERNAL PC

Network

processed

digital

images

to network

1. The 2 PMTs connect to the PMT/DAS BOARD A5. The HIGH VOLTAGE POWER SUPPLY

feeds power to the HIGH VOLTAGE DIVIDERS. Each PMT has a HIGH VOLTAGE DIVIDER that sends the given levels of high voltage to the components inside the PMTs.

2. The ANODE of each PMT is connected to a CURRENT-TO-VOLTAGE AMPLIFIER, which

changes the small current signal from each PMT into a corresponding voltage signal. Each of the voltage signals moves through a PMT GAIN CONTROL D/A CONVERTER. These CONVERTERS change the signal level from each PMT to adjust for gain variations from PMT to PMT.

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3. The corrected signals are added together in the SUMMING AMPLIFIER. An offset

adjustment signal is added to adjust for any other offset error. The offset signal is provided by 2 D/A CONVERTERS that allow large and small adjustments. The offset adjustment signal causes the signal to be 0 when no light hits the PMTs.

4. The adjusted signal is sent through the correct LOW PASS FILTER for noise reduction:

• GP resolution - 300 KHz

• EHR - 1 MHz

5. The filtered signal is sent to the 16-BIT A/D CONVERTER for measurement of the

brightness of the blue light emitted by the SCREEN. The intensity of the blue light is proportional to the charge stored by the PHOSPHOR and the intensity of the laser beam that hit the PHOSPHOR. To constr uct the original image again, it is necessary to know the strength of the laser beam when the blue light was measured.

6. The PMT/DAS BOARD A5 includes logic circuits that interface with the IEB BOARD A2.

This serial data interface allows for the adjustment of the A/D CONVERTERS on the PMT/ DAS BOARD A5. The PIXEL CLOCK connects to the A/D CONVERTER and sends a command to make a measurement. The A/D CONVERTER makes a 16-bit value for each measurement.

7. The image is sent to the IEB BOARD A2 in serial format one pixel at a time. The data is

stored in a FIFO BUFFER until a complete line of data is received. The raw image data is sent to the RAM. When all the data for a given image is in the RAM, the IEB BOARD A2 sends the full raw image to the EXTERNAL PC for processing and distribution to the hospital network.

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THEORY GUIDE Scan/Erase

Section 7: Scan/Erase

Overview

from IEB BOARD

H219_7515HCA H219_7515HC

MINI-MCB

BOARD

PLATE POSITIONING AY

EXTRACTION BAR

SLOW SCAN MOTOR

CASSETTE SHELL and PLATE

ERASE LAMPS

LEAD SCREW

COIL BOARD A7

ENCODER

The Scan/Erase subsystem moves the PLATE:

• through the field of scan at a constant speed

• to the ERASE AY to be erased

• up to be inserted into the CASSETTE SHELL

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The Scan/Erase subsystem includes:

• PLATE SUPPORT AY - Version 1, or

• PLATE SUPPORT AY - Version 2

• LEAD SCREW

• EXTRACTION BAR

• REFERENCE SENSOR S5

• PLATE PRESENT SENSOR S6

• SLOW SCAN MOTOR

• ENCODER

• ERASE AY

• LAMP CURRENT SENSORS CS1 - CS5

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THEORY GUIDE Scan/Erase

PLATE SUPPORT AY - Version 1

The ARM of the PLATE SUPPORT AY keeps the PLATE in the correct vertical position for removal from the CASSETTE, for scanning, and for inserting the PLATE into the CASSETTE SHELL after scanning.

The PLATE SUPPORT AY has a single ARM. A ROLLER BEARING on the SLOW SCAN AY controls the position of the ARM.

The ARM rotates forward until it touches the back of the PLATE. After the ARM touches the PLATE, the ROLLER BEARING releases contact with the ARM, and the SPRING for the ANTI-REVERSE AY holds the contact between the ARM and the PLATE.

The ANTI-REVERSE AY:

• prevents the ARM from moving backward

• has a BOOST MECHANISM that lightly

pushes the PLATE toward the COLLECTOR to create clearance between the PLATE and the CASSETTE. The clearance prevents the PLATE from touching the WALLS of the CASSETTE when the PLATE moves out of the CASSETTE.

PLATE SUPPORT AY

ANTI-REVERSE AY

SPRING

EXTRACTION

EXTRACATION BAR

H219_7523GCA H219_7523GC

PLATE

BOOST MECHANISM

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THEORY GUIDE Scan/Erase

PLATE SUPPORT AY - Version 2

PLATE

PLATE SUPPORT AY

STOP AY

The ARM of the PLATE SUPPORT AY keeps the PLATE in the correct vertical position for removal from the CASSETTE, for scanning, and for inserting the PLATE into the CASSETTE SHELL after scanning.

A ROLLER BEARING on the SLOW SCAN AY controls the position of the PLATE SUPPORT AY.

When the SLOW SCAN AY moves down to remove the PLATE from the CASSETTE, the PLATE SUPPORT AY rotates forward until it touches the back of the PLATE. After the PLATE SUPPORT AY touches the PLATE, it continues to move forward until it touches the STOP AY.

The PLATE SUPPORT AY has 2 main components:

EXTRACTION

EXTRACATION BAR

H219_7520GCA H219_7520GC

• MOUNTING ARM - after the

POSITIONING ARM touches the PLATE, the MOUNTING ARM stops moving. The SLOW SCAN AY continues to remove the PLATE from the CASSETTE.

• SUPPORT ARM - as the SLOW SCAN

AY continues to remove the PLATE from the CASSETTE, the SUPPORT ARM continues to rotate forward until it reaches the STOP. The SUPPORT ARM pushes the PLATE from the back of the CASSETTE SHELL when it leaves the CASSETTE.

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THEORY GUIDE Scan/Erase

LEAD SCREW

The LEAD SCREW is connected to the MOTOR SHAFT. When the LEAD SCREW rotates, it moves the EXTRACTION BAR up and down.

EXTRACTION BAR

Home position Reference

position

Start of scan position

End of scan position-fixed

Erase position

H219_7516GCA

H219_7516GC

The EXTRACTION BAR holds the PLATE when it moves down during scanning and up after erasing.

Note

The PLATE is not visible in the graphic.

THEORY GUIDE Scan/Erase

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The EXTRACTION BAR has 5 vertical positions.

Position of the

EXTRACTION BAR

Description

Reference position Position of the EXTRACTION BAR when the REFERENCE SENSOR

S5 is blocked. The REFERENCE SENSOR S5 is installed at this position during manufacture. This position is not the same for all CLASSIC/ELITE CR SYSTEMS.

When the system is initialized, the EXTRACTION BAR checks for the REFERENCE SENSOR S5. Once it is located, the EXTRACTION BAR moves up to the home position 1. The EXTRACTION BAR remains at the home position 1 until the start of a new cycle.

Home position Position of the EXTRACTION BAR at the start and end of a cycle.

Home position is 3.8 - 4.5 cm (1.5 - 1.75 in.) above the position of the REFERENCE SENSOR. The home position is set in the factory, but can be adjusted in the field if necessary.

Start of scan position

Position of the EXTRACTION BAR when the SCREEN is in position to be scanned. The start of scan position is a set number of counts of the ENCODER below home position. The number of counts of the ENCODER defines the mechanical start of scanning. The optical start of scanning occurs after the IEB BOARD A2 sends a message to the GALVO to start scanning t he SCREEN. For more information about the ENCODER, see ENCODER.

End of scan position The end of scan is defined by counts of the ENCODER, determined

by the size of the PLATE.

Erase position Position below the end of scan when the PLATE is located directly in

front of the ERASE LAMPS. The erase position is determined by the size of the PLATE.

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THEORY GUIDE Scan/Erase

REFERENCE SENSOR S5

The REFERENCE SENSOR S5 checks for a FLAG on the EXTRACTION BAR that provides the SLOW SCAN AY with the reference position. All other positions of the SLOW SCAN AY are relative to the reference position.

PLATE PRESENT SENSOR S6

After the PLATE is fastened by the EXTRACTION BAR, it is pulled down by the SLOW SCAN AY. The PLATE moves between the EMITTER and DETECTOR of the PLATE PRESENT SENSOR S6. The MINI-MCB BOARD A1 reads the status of the SENSOR and determines if a PLATE is loaded before continuing the slow scan operation.

SLOW SCAN MOTOR

LEAD SCREW

RS-232

connection to

IEB BOARD A2

MINI-MCB

BOARD

H219_7505BC

COIL BOARD CABLE

COIL BOARD A7

MAGNET

FLYWHEEL

ENCODER CABLE

ENCODER

fixed to shaft

The SLOW SCAN MOTOR is a 3-phase DC MOTOR that provides all vertical motion of the PLATE necessar y for scanning and erasing operations.

THEORY GUIDE Scan/Erase

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The following components control the operation of the SLOW SCAN MOTOR:

Component Description

MINI-MCB BOARD A1Controls the motions of the SLOW SCAN MOTOR. The COIL BOARD

A7 and the ENCODER connect to this BOARD. Normally, the parameters of motion of the MOTOR include:

• direction of motion - clockwise or counterclockwise

• number of counts of the ENCODER that the MOTOR must move

• acceleration

• running speed

• deceleration

SLOW SCAN MOTOR

Includes:

• STEEL PLATE - operates with the COIL BOARD A7 to generate

the MAGNET that causes torque in the SLOW SCAN MOTOR

• COIL BOARD A7 - keeps the correct rotation of the SLOW SCAN

MOTOR

• MAGNET/FLYWHEEL - a steel CYL INDER with a MAGNET at the

top end that adds rotating mass to the MOTOR and makes the rotation smooth

ENCODER Monitors the speed and position of the MAGNET to provide:

• smooth operation of the MOTOR

• speed of the MOTOR that does not change

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THEORY GUIDE Scan/Erase

MAGNET

HALL EFFECT SENSORS

THERMAL

H194_5039AC

FUSES

The COIL BOARD A7 includes:

• 6 TRIANGULAR-SHAPED COILS of wire around the CENTRAL SHAFT of the MOTOR

• 3 HALL EFFECT SENSORS, which detect magnetic fields. The SENSORS determine the

position of the MAGNET POLES relative to the COILS

• 3 THERMAL FUSES, which protect the components if a COIL is too hot or other

malfunctions occur

The COIL BOARD A7 and the MAGNET operate together to rotate the MOTOR.

1. The HALL EFFECT SENSORS determine the polarization of the MAGNET when the

MAGNET is aligned with the COILS.

2. The MINI-MCB BOARD A1 changes the amplitude and direction of the current flow in the

COILS to make a magnetic field.

3. The MAGNET rotates to align with the magnetic field.

4. The process continues, providing a smooth rotation of the MOTOR.

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Obtaining Smooth Operation of the SLOW SCAN MOTOR

To obtain smooth operation of the SLOW SCAN MOTOR, it is necessary to have smooth rotating torque. The COILS make a magnetic field and the MAGNET aligns with the COILS. When the MAGNET POLES are almost in alignment with the magnetic field, the torque potential is highest. When the MAGNET rotates out of perfect alignment, more current is necessary in the COILS to provide the same quantity of torque.

To provide the smoothest torque, the MINI-MCB BOARD A1 uses a sinusoidal current in the COILS. When the polarization of the MAGNET is most out of alignment with the magnetic field of the COIL, the sinusoidal current is at the maximum. When the MAGNET and the field are almost perfectly aligned, the current drops to almost 0. The current in the COIL then changes to negative polarity to repel the MAGNET POLE and continue the smooth torque. When the next POLE starts to approach, the current reverses direction and reaches the maximum again.

The MINI-MCB BOARD A1 monitors the signals from the ENCODER when the MOTOR is operating. If the MOTOR is operating too slowly, the MINI-MCB BOARD A1 increases the peak of the COIL current sinuosity to provide more torque to increase the speed. If the MOTOR is operating at a higher speed than it should, it decreases the current.

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THEORY GUIDE Scan/Erase

ENCODER

LIGHT EMITTER

LIGHT DETECTOR 1

ENCODER WHEEL

( 5000 Lines )

LIGHT EMITTER

Signal from DETECTOR 1

Signal from DETECTOR 2

LIGHT DETECTOR 2

H194_5031BC

The ENCODER monitors the speed and position of the MAGNET during rotation to provide smooth operation and continual speed.

Component Description

ENCODER WHEEL A clear disk that has 5000 lines leading from the center to the

outside edge.

2 OPTICAL SENSORS EMITTER/

Placed at the edge of the ENCODER WHEEL. Each beam from the EMITTER/DETECTOR is blocked by the lines of the WHEEL when the WHEEL rotates.

DETECTORS

The signals of the SENSORS are 90 degrees out of phase with each other in a “quadrature relationship.” One DETECTOR detects the edge of a line and the other detects the middle of the line.

The ENCODER determines:

• speed of the SLOW SCAN MOTOR by measuring the frequency of the signals

• direction of rotation of the SLOW SCAN MOTOR by determining the sequence in which

the signals change

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The signals from the 2 SENSORS are continually monitored by the MINI-MCB BOARD A1, and the power to the COIL BOARD A7 is decreased or increased to provide smooth rotation and continual speed.

20,000 counts of the ENCODER make one rotation of the LEAD SCREW. The system moves to each of the following positions until it reaches the correct number of counts:

• start of scan

• erase

• end of scan

ERASE AY

The ERASE AY includes 5 pairs of highintensity ERASE LAMPS that expose the

ERASE LAMPS

scanned SCREEN to white light. This operation releases any residual charge on the SCREEN.

PLATE

SLOW SCAN MOTOR

H219_7522GCA

H219_7522GC

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1. The IEB BOARD A2 sends an “Erase” command to the MINI-MCB BOARD A1, which

sends a signal to the SLOW SCAN MOTOR to start the erasing operation.

2. The SLOW SCAN MOTOR actuates and moves the PLATE into the erase position

determined by the ENCODER counts.

3. The SLOW SCAN MOTOR stops and waits for a response from the IEB BOARD A2.

4. The IEB BOARD A2 sends the “Erase” command and time to the MINI-MCB BOARD A1,

which actuates the ERASE LAMPS.

5. The ERASE LAMPS illuminate for 2 - 16 seconds to remove the image from the SCREEN.

6. When the SCREEN is erased, the MINI-MCB BOARD A1 sends the “Erase Done” status

to the IEB BOARD A2.

Note

• The MINI-MCB BOARD A1 and the IEB BOARD A2 are not visible in the graphic.

• The length of time the ERASE LAMPS illuminate is determined by the highest pixel code

value of the image that was scanned. If one pair of LAMPS is not operating, the time increases by a factor of 2. If more than one pair of LAMPS is not operating, a message displays on the MONITOR.

LAMP CURRENT SENSORS CS1 - CS5

Each pair of ERASE LAMPS has one BALLAST. A LAMP CUR RENT SENSOR monitors the electrical current to each BALLAST.

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THEORY GUIDE Imaging Sequence

Section 8: Imaging Sequence

Overview

EXTERNAL

motion

commands

HOSPITAL NETWORK

LUI

IEB

BOARD

digital image

data

PMT/DAS

BOARD

A/D

CONVERTER

analog

image data

blue light

red

laser

light

H219_7519DC

RS-232

A17

LASER DIODE

DRIVER BOARD

LASER

MINI-MCB

BOARD

THEORY GUIDE Imaging Sequence

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The CLASSIC/ELITE CR SYSTEM uses the components of the Optical and Scan/Erase subsystems to make the digital images. The imaging sequence includes:

• Scanning the SCREEN - Slow Scan/Fast Scan

• Obtaining the Image Data

• Processing the Data

• Processing the Image

Scanning the SCREEN - Slow Scan/Fast Scan

PLATE

fast scan motion

throwaway

lines

2048 - 2392

amplitude

slow scan motion

offset

H194_5040AC

1 When the PLATE reaches the mechanical “Star t Of Scan” position, the MINI-MCB

BOARD A1 sends a message to the IEB BOARD A2 that the SCREEN is ready for scanning.

THEORY GUIDE Imaging Sequence

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2 The IEB BOARD A2 sets up the GALVO SYSTEM and PMT/DAS BOARD A5 with the

following information recorded during calibration of the CLASSIC/ELITE CR SYSTEM:

• offset and amplitude of the GALVO

• gain of the PMTs

• high voltage of the PMTs

• number of pixels/line

• number of lines to scan

• offset for start of fast scan

Note

The number of lines scanned includes the lines scanned for the image and also the “throwaway lines”. “Throwaway” lines at the beginning of the scanning are lines that are scanned but are not part of the image.

On GP and HR PLATES, the star t and stop of the fast scan is approximately 10 pixels in from the edge of the PHOSPHOR. The actual distance will vary from approximately 1 mm for small CASSETTES to approximately 5 mm for larger CASSETTES, because the pixel size is smaller on the small CASSETTES. This START/STOP OFFSET is determined at the calibration of the CASSETTE.

EHR MAMMOGRAPHY and LLI CASSETTES perform an overscan which shows the edge of the SCREEN.

3 The IEB BOARD A2 sends messages to:

• MINI-MCB BOARD A1 to start the slow scan

• PMT/DAS BOARD A5 to star t the collection of data

• start the GALVO MOTOR

4 The GALVO starts and provides the deflection of the laser beam onto the SCREEN. The

laser beam moves horizontally across the SCREEN. This horizontal motion is the fast scan direction. See GALVO.

THEORY GUIDE Imaging Sequence

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5 At the same time, the SCREEN moves vertically. This vertical motion is the slow scan

direction. Both motions are determined by calibration data for the given SCREEN size. The

MINI-MCB BOARD A1 controls the slow scan motion. The IEB BOARD A2 controls the fast scan motion.

Obtaining the Image Data

analog signal

LIGHT COLLECTOR

PMT

(1 of 2)

BLUE FILTER

red laser light

blue light

H194_5009GC

PHOSPHOR SCREEN

1 The red laser beam scans across the PHOSPHOR SCREEN in the fast scan direction.

When it hits the PHOSPHOR charged by the X-ray exposure, it causes the PHOSPHOR to emit blue light. The brightness of the blue light is proportional to the strength of the X-ray and the power of the LASER at the point it hits the PHOSPHOR. The light is emitted in a random pattern.

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2 The collection of random blue light is provided by the COLLECTOR, which reflects the

light toward the FACES of the 2 PMTs:

• for each line of the fast scan, a given number of measurements is made, determined

in the IEB BOARD A2 by the size of the SCREEN. This is the “sampling rate.” The sampling rate defines the size of each pixel of information that is read from the SCREEN. For more information about sampling, see Changing Analog Signals to

Digital Signals.

• both the red light from the LASER and the blue light emitted from the PHOSPHOR is

emitted toward the COLLECTOR. A BLUE FILTER prevents the red light from entering the PMTs. The BLUE FILTER allows only the blue light into the PMTs.

3 The PMTs change the light energy into analog electrical current signals. 4 The output from each of the 2 PMTs is sent to the PMT/DAS BOARD A5. The PMT/DAS

BOARD A5 changes and amplifies the output to a proportional voltage signal.

5 Gain control is applied to each of the voltage signals to correct for gain variations from

the 2 PMTs.

6 The SUMMING AMPLIFIER adds the corrected signals and an offset adjustment signal is

also added. This new signal is sent through a LOW PASS FILTER for noise reduction.

7 The voltage signal is sent through a 16-bit ANALOG-TO-DIGITAL (A/D) CONVERTER,

which changes it to a 16-bit digital signal.

8 The 16-bit image data is sent in a serial-data stream to the FPGA in the IEB BOARD A2.

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THEORY GUIDE Imaging Sequence

Processing the Data

1 The pixels are stored in a FIFO BUFFER in the FPGA on the IEB BOARD A2. The data

is stored in the FIFO BUFFER in the FPGA until a complete line of data is received.

2 In rapid sequence, when the GALVO is moving to the start of the next line:

• each line is moved to RAM on the IEB BOARD A2 using Direct Memory Access

(DMA)

• after the data is in the RAM, image processing starts 3 The GALVO begins to scan the next line on the SCREEN. 4 When the GALVO is scanning the next line, the IEB BOARD A2 processes the last line

received. During this time, the IEB BOARD A2 applies the “Collector Profile” to each pixel to adjust for any change in the efficiency of the COLLECTOR.

5 The IEB BOARD A2 changes the pixels from 16-bit linear values to 12-bit log values.

Each pixel has a value between 0 - 4095. The image is now a “raw image” that is formatted. The image is stored in a BUFFER on the IEB BOARD A2.

Note

When the bar code is read and the CASSETTE moves to the load position, the EXTERNAL PC sets up a raw image file to receive the raw image from the IEB BOARD A2. The size of the file is determined by the size of the SCREEN.

6 The IEB BOARD A2 sends the full raw image to the EXTERNAL PC line-by-line. 7 When the IEB BOARD A2 determines that the number of lines are scanned for the size

of the SCREEN, the PLATE is sent to be erased.

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THEORY GUIDE Imaging Sequence

Processing the Image

1 When the software on the EXTERNAL PC detects that a raw image was received from

the IEB BOARD A2, the software:

• places the data in a prepared raw image file

• checks the CASSETTE ID

• locates the patient record that matches the CASSETTE ID 2 The software on the EXTERNAL PC:

• calculates the BLACK SURROUND MASK (BSM) used for making the areas outside

the image black. The software automatically detects more than one exposure on any CASSETTE

• uses the body part and “projectile” information, and the image to deter mine the

necessary processing parameters

• uses the processing parameters to calculate a digital density Look-up Table (LUT),

and gain tables, and applies them to the image. The gain tables include:

– “Tonescale” – sharpness – noise correction

• makes preview and thumbnail size images to display

Note

The full 6.5 - 60 MB raw image is stored on the HARD DRIVE of the CLASSIC/ELITE CR SYSTEM. The image viewer allows you to view the image at 100% size.

3 The operator touches or clicks the thumbnail image on the MONITOR. The operator

makes changes and corrections to the subsample image and stores the changes. The software applies all the processing changes to the full resolution image and stores the changes in the database. The changes are applied to the image that is sent to any network nodes.

THEORY GUIDE Imaging Sequence

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4 The internal CR SYSTEM software, called the Medical Image Manager (MIM) software,

adds the Digital Imaging and Communication in Medicine (DICOM) information to the image file.

5 The MIM software makes a copy of the DICOM file and sends information from that file

to all network nodes. The MIM software recognizes the features of each node and adjusts the image for correct viewing at each node.

Note

After the MIM sends the processed image, the DICOM file is deleted. The original raw image file and all the processing parameters are stored in a database directory of the EXTERNAL PC for possible use at another time. The database has a maximum storage level, after which a program automatically deletes the raw image, thumbnail files, and all associated information.

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THEORY GUIDE Logic and Control

Section 9: Logic and Control

Overview

Hospital

CLASSIC/ELITE CR SYSTEM

PMT/DAS

BOARD

USER

INTERFACE

EXTERNAL PC

To Hospital Network

DICOM - TCP/IP

EXTERNAL BAR CODE

READER

MOUSE

MONITOR

IEB

BOARD

A17

LASER DIODE

DRIVER BOARD

H219_7506HC

GALVO MOTOR M4

The Logic and Control subsystem:

• processes commands from the operator

• controls the operation of all subsystems

COIL

BOARD

KEYBOARD

MINI-MCB

BOARD

SLOW SCAN

ENCODER

RJ-45 PLUG

INTERNAL BAR

CODE READER

• sends processed images to the network for distribution

THEORY GUIDE Logic and Control

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The Logic and Control subsystem includes:

• Operator Input Components

• BOARDS

• Distribution of Images to the Network

Operator Input Components

MONITOR

The MONITOR allows the operator to enter information for an exam into the CLASSIC/ELITE CR SYSTEM. The display of the MONITOR has a menu and control system.

The MONITOR for the ELITE CR SYSTEM is a TOUCH SCREEN. The standard MONITOR for the CLASSIC CR SYSTEM is not a TOUCH SCREEN, but the customer can purchase an optional TOUCH SCREEN.

The EXTERNAL PC provides the screen format for each menu item selected. The MONITOR enables the operator to select a displayed menu item or control by touching the SCREEN, or by moving and clicking the MOUSE. This action sends a command to the CLASSIC/ELITE CR SYSTEM. The EXTERNAL PC sends the necessary data to do that action. CONTROL BUTTONS on the MONITOR allow the user to select functions and to move to other menus or functions.

VIRTUAL KEYBOARDS for entering information into the CLASSIC/ELITE CR SYSTEM display on the MONITOR. The configuration of the KEYBOARD is determined by the type of information to be entered. Each KEYBOARD automatically displays when a menu item is selected to enter data.

The system also uses typed input from a PHYSICAL KEYBOARD connected to the EXTERNAL PC.

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THEORY GUIDE Logic and Control

Main Menu

The main menu provides access to the controls for the operation and service of the CLASSIC/ELITE CR SYSTEM. The following table describes the menu items that are available to operators. Each type of operator has a password that allows access to the indicated menu items.

Under “Study Data”, you can:

• enter or retrieve patient information

• make a “Study” with a series of images

Under “Image Review”, you can:

• review images

• send images to a DESTINATION

• check for correct exposure of an image

THEORY GUIDE Logic and Control

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Under “Key Operator Functions”, you can:

• set “Looks Preferences”

• set “Procedure Code Mapping”

• configure “Image Review Palettes”

• configure “Patient Input” screens

Operator Type Can View Main Menu Items: Description

Operator • Study Data

Operators can view patient data and images.

• Image Review

Ke y Operator • Key Operator

Functions

• Study Data

• Image Review

Security Administrator

• Security Administrator

• Key Operator

Functions

• Study Data

Key Operators can:

• set up system and image processing default

parameters

• view patient data and images

Security Administrator can:

• set up the MONITOR, SMPTE Test Pattern,

and Diagnostic Image configuration

• set up system and image processing default

parameters

• Image Review

• view patient data and images

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THEORY GUIDE Logic and Control

Operator Type Can View Main Menu Items: Description

Service Provider

• Service Functions

• Security Administrator

Service Providers can:

• have access to diagnostic and service

menus, including:

• Key Operator

Functions

• Study Data

• Image Review

– diagnostics – configuration of formats for the bar code – configuration of the network

• set up the MONITOR, SMPTE Test Pattern,

and Diagnostic Image configuration

• set up default system and image processing

parameters

• view patient data and images

LOCAL USER INTERFACE (LUI)

The LUI is a TOUCH SCREEN INTERFACE BOARD that provides a local interface to the CLASSIC/ELITE CR SYSTEM. The LUI provides access to Utility menus, service functions, and provides error and status display.

The LUI has a 100-BaseT connection with the IEB BOARD A2, and provides TCP/IP and FTP SERVER support.

The LUI is a QVGA (320 x 240 pixel) RGB TFT LCD with a TOUCH SCREEN. The LUI includes an audible device.

THEORY GUIDE Logic and Control

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BOARDS

The BOARDS control the operation of the CASSETTE HANDLING, Optical, and Scan/Erase subsystems and the imaging sequence of the CLASSIC/ELITE CR SYSTEM.

BOARD Description

MINI-MCB BOARD A1

Controls the electro-mechanical devices in the CLASSIC/ELITE CR SYSTEM, including:

• motion of the CLAMP MOTOR

• illumination of the ERASE LAMPS

• motion of the HOOKS MOTOR

The MINI-MCB BOARD A1 also:

• controls the SLOW SCAN MOTOR that provides an interface to: – remove the PLATE from the CASSETTE before scanning and

insert the PLATE back into the CASSETTE after scanning

– control the slow scan motion of the PLATE during scanning – control the motion of the PLATE when it moves to and from

the erase position

• provides an interface for the INTERNAL BAR CODE READER

• controls all vertical motion of the PLATE in a continual motion.

This motion is at a right angle to the direction of the horizontal fast scan motion of the LASER.

• connects to the COIL BOARD A7 in the SLOW SCAN MOTOR to

drive the COILS and read the HALL EFFECT SENSORS

• connects to the ENCODER at the bottom of the SLOW SCAN

MOTOR ASSEMBLY

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THEORY GUIDE Logic and Control

BOARD Description

IEB BOARD A2 The BOOT CODE of the IEB BOARD A2:

• provides configuration information for the MICRO CONTROLLER

• starts the application program for the CLASSIC/ELITE CR

SYSTEM

• checks that signals can be sent to the EXTERNAL PC

The IEB BOARD A2:

• obtains raw image data

• changes the image data from 16-bit linear to 12-bit log data

• actuates the LASER

• provides correction of the “Collector Profile” for the image data

• sends the image to the EXTERNAL PC for image processing and

viewing

• provides the scanning parameters determined by the size of the

SCREEN to be scanned

• records the maximum pixel value of a scan to allow the “smart

erase” algorithm to calculate the time to erase the SCREEN

• provides an interface to the MINI-MCB BOARD A1

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THEORY GUIDE Logic and Control

BOARD Description

IEB BOARD A2 (continued)

• The FPGA on the IEB BOARD A2: – controls the SPI to the PMT/DAS BOARD A5 – obtains the image data from the PMT/DAS BOARD A5 and

sets up timing and control to the PMT/DAS BOARD A5 and the GALVO

– synchronizes the start and horizontal motion of the GALVO

fast scan and the PMT/DAS A/D CONVERTERS that obtain the data

– receives image data one pixel at a time from the PMT/DAS

BOARD A5 and stores the data in a FIFO BUFFER until a line is completed. One pixel is made of 16-bit segments.

– starts DMA transfer of the image data from the FIFO BUFFER

to the FPGA when each line is completed

• The IEB BOARD A2: – provides drive and feedback signals to control the position of

the GALVO MIRROR that provides the deflection of the laser beam onto the SCREEN during the fast scan operation

– sends data to the GALVO CONTROL, then sends timing

signals to command the GALVO to move the MIRROR through a full line cycle

– provides timing and control of the LASER DIODE DRIVER

BOARD A17

• At the end of the cycle, the GALVO CONTROL sends a signal to

the IEB BOARD A2 to indicate that the line is completed.

• A closed loop SERVO CIRCUIT uses the POSITION SENSORS

in the GALVO to keep the speed of the MIRROR smooth and in the position necessary for the maintenance of image quality.

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THEORY GUIDE Logic and Control

BOARD Description

PHOTOMULTIPLIER TUBE/ DATA AQUISITION

Amplifies, adds, and filters the data from the 2 PMTs, then changes the analog data to digital data. The PMT/DAS BOARD A5 also supplies power to the 2 PMTs.

SYSTEM (PMT/DAS)

- A5 COIL - A7 Includes 6 triangular-shaped WIRE COILS around the CENTRAL

SHAFT of the SLOW SCAN MOTOR. At the outside edge of the COILS are 3 HALL EFFECT SENSORS. These components work with the SLOW SCAN CONTROLLER and the MAGNET of the SLOW SCAN MOTOR to rotate the MOTOR.

LASER DIODE DRIVER - A17

Includes a LASER DIODE that provides the red laser light used to scan the SCREEN. The IEB BOARD A2 controls the operation of the LASER DIODE DRIVER BOARD A17.

LOCAL USER INTERFACE (LUI) BOARD

The LUI:

• provides a local interface to the system

• allows the operator to view messages

Distribution of Images to the Network

Overview

The EXTERNAL PC receives raw images from the IEB BOARD A2, processes the images, and stores or sends the images to given nodes in the hospital network. Ethernet CABLES connect both the IEB BOARD A2 and the EXTERNAL PC to the hospital network.

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Sequence of Operation

1. When the CLASSIC/ELITE CR SYSTEM has made a raw image, a new folder is created

in the DATABASE of the EXTERNAL PC for the image and associated other files. The name of the new folder is “C:\inetpub\wwwroot\images\<DB guid>_<custom extension>”.

2. The “RawImageProcessing Service” creates the following files in the folder:

• “<XXX>.raw” - the raw image is named by the acquisition service

• “Catalog.xml” - a list of the files stored in the folder

• “State.xml” - internal image processing information

• “Thumbnail.163.200.raw” - the thumbnail image. The width and height of the thumbnail

are indicated in the name of the file.

• “Processed.2048.2500.raw” - full size image. The width and height of the full size

image are indicated in the name of the file.

• “Preview.901.1100.raw” - preview image. The width and height of the preview are

indicated in the name of the file.

• “Exposure.0.unprocessed.2048.2500.raw” - raw, full size field image

• “Exposure.0.subsample.227.277.raw” - raw, sub-sampled exposure field data

• “Exposure.0.digital.4096.UInt16” - the LUT generated during “Eclipse” processing

• “Exposure.0.anatomy.227.277.mask” - raw, sub-sampled anatomy MASK for the

exposure field

• “Display.4096.UIint16” - LUT to change GSDF output for display

3. Any event can cause an image review to occur:

• “Pass-Thru Mode” - the image is advanced with no review

• “QA Mode” - image review is necessary, and the user must click [Accept]

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4. Temporar y files for the MIM are created in a new folder with the name “C:\Program

Files\KodakCaptureConsole\bin\MIM Core\Images\<id>”:

• “<id>_processed.tif” - 12-BIT “.tif” image file

• “<id>_dam.xml” - job setup - print, store, page layout, etc.

• “<id>_clinical.xml” - all the DICOM TAGS to be put in the output DICOM file

5. The MIM controls all the DICOM communication.

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THEORY GUIDE Power Distribution

Section 10: Power Distribution

Overview

+24V DC

GALVO

MOTOR

PMT Power

Interface

Cable

PMT

BOARD

LASER

BOARD

BARCODE

READER

A17

PS1

POWER

SUPPLY

+24V DC

-24V DC

DISPLAY/

USER

INTERFACE

+24V DC

-24V DC

IEB

100-240V

AC Source

100-240AC

50/60 Hz

H219_7510DC

EXTERNAL

INPUT

VOLTAGE

JUMPER

TRANSFORMER

120VAC

ISOLATION

Front Door

Interlock

+24V DC

-24V DC

MINI_MCB

Relay Relay

K1-

RELAY

120VAC

MOTORS

HOOKS CLAMP

SLOW-SCAN

ERASE LAMPS

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The Power Distribution subsystem includes:

• POWER SUPPLY

• Power Distribution

• INTERLOCK

• TRANSFORMER T1

POWER SUPPLY

The CLASSIC/ELITE CR SYSTEM operates correctly when connected to the power sources described in the table below. These voltages can be obtained from a line-and-neutral or lineto-line connection. For all voltages, only a single-phase power distribution system is necessary.

The input power is changed at the TRANSFORMER T1 to an output voltage of 120 V AC. No additional FILT ERS, TRANSFORMERS, or other devices are necessary to provide correct operating voltage. When installing the CLASSIC/ELITE CR SYSTEM, you must set the VOLTAGE SELECTION JUMPER for the voltage at the site.

VOLTAGE

Voltage Tolerance Current Frequency

100 V AC ±10% 10 A 50/60 Hz 100 V

SELECTION

JUMPER

110 VAC ±10% 10 A 50/60 Hz 120 V 115 V AC ±10% 10 A 50/60 Hz 120 V AC +10%, -13% 10 A 50/60 Hz 127 V AC ±10% 10 A 50/60 Hz 200 V AC ±10% 5 A 50/60 Hz 200/208 V 208 V AC ±10% 5 A 50/60 Hz 220 V AC ±10% 5 A 50/60 Hz 230 V 230 V AC ±10% 5 A 50/60 Hz 240 V AC +6%, -10% 5 A 50/60 Hz

Kodak DirectView User manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Section 1: Equipment Description

Features and Functions

Main Subsystems

Section 2: Radiography Theory

Comparison of Film/Screen and Computed Radiography (CR)

Overview of CR Technology

Operations

Exposing the STORAGE PHOSPHOR SCREEN

Stimulating the PHOSPHOR

Changing Light Energy to an Analog Signal

Changing Analog Signals to Digital Signals

Processing the Digital Image

Section 3: Sequence of Operation

Overview of Workflow Using the CLASSIC/ELITE CR SYSTEM

Before Loading the CASSETTE

Loading the CASSETTE

Removing the PLATE from the CASSETTE

Scanning the SCREEN

Erasing the SCREEN

Inserting the PLATE back into the CASSETTE SHELL

Removing the CASSETTE

Section 4: STORAGE PHOSPHOR CASSETTE

Overview

Size and Resolution of SCREENS

Fast Scan / Slow Scan Directions

Image Matrix Size

Reading the BAR CODE LABEL of the CASSETTE

Section 5: CASSETTE HANDLING

Overview

CASSETTE Load

EXTRACTION BAR MOTOR AY

CLAMP MOTOR

PLATE HANDLING

Section 6: Optical

Overview

LASER

GALVO

COLLECTOR and PHOTOMULTIPLIER TUBE (PMT)

Section 7: Scan/Erase

Overview

PLATE SUPPORT AY - Version 1

PLATE SUPPORT AY - Version 2

LEAD SCREW

EXTRACTION BAR

REFERENCE SENSOR S5

PLATE PRESENT SENSOR S6

SLOW SCAN MOTOR

ENCODER

ERASE AY

Section 8: Imaging Sequence

Overview

Scanning the SCREEN - Slow Scan/Fast Scan

Obtaining the Image Data

Processing the Data

Processing the Image

Section 9: Logic and Control

Overview

Operator Input Components

MONITOR

LOCAL USER INTERFACE (LUI)

BOARDS

Distribution of Images to the Network

Overview

Sequence of Operation

Section 10: Power Distribution

Overview

POWER SUPPLY