Baumer VLU-02M, VLU-02C, VLU-12M, VLU-12C, VLU-03M User Manual

User's Guide

VisiLine cameras (USB3 Vision™)

Document Version: v1.0
Release: 24.09.2014
Document Number: 11135443

2

3

Table of Contents

1. General Information ................................................................................................. 6

2. General safety instructions ..................................................................................... 7

3. Intended Use ............................................................................................................. 7

4. General Description ................................................................................................. 8

5. Camera Models ......................................................................................................... 9

6. Installation .............................................................................................................. 10

6.1 Lens mounting ...................................................................................................... 10

6.2 Environmental Requirements ................................................................................ 10

6.2.1 Heat Transmission ...........................................................................................11

7. Pin Assignment ...................................................................................................... 12

7.1 USB 3.0 Interface .................................................................................................. 12

7.2 Digital IOs ............................................................................................................. 12

7.2.1 LED Signalling ................................................................................................ 13

8. ProductSpecications .......................................................................................... 14

8.1 Spectral Sensitivity for Baumer VLU Cameras ..................................................... 14

8.2 Field of View Position ............................................................................................ 15

8.3 Acquisition Modes and Timings ............................................................................. 16

8.3.1 Free Running Mode ........................................................................................ 16

8.3.2 Fixed-Frame-Rate Mode ................................................................................ 17

8.3.3 Trigger Mode .................................................................................................. 18

8.3.4 Advanced Timings for USB 3.0 Vision

TM

Message Channel ........................... 22

8.4 Software ................................................................................................................ 24

8.4.1 Baumer GAPI ................................................................................................. 24

8.4.2 3

rd

Party Software ........................................................................................... 24

9. Camera Functionalities .......................................................................................... 25

9.1 Image Acquisition .................................................................................................. 25

9.1.1 Image Format ................................................................................................. 25

9.1.2 Pixel Format ................................................................................................... 26

9.1.3 Exposure Time................................................................................................ 28

9.1.4 PRNU / DSNU Correction (FPN - Fixed Pattern Noise) ................................. 29

9.1.5 HDR (High Dynamic Range) .......................................................................... 30

9.1.6 Look-Up-Table ................................................................................................ 31

9.1.7 Gamma Correction ......................................................................................... 31

9.1.8 Region of Interest (ROI) ................................................................................. 32

9.1.9 Binning............................................................................................................ 33

9.1.10 Brightness Correction (Binning Correction) .................................................. 34

9.1.11 Flip Image ..................................................................................................... 35

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9.2 Color Processing ................................................................................................... 36

9.3 Color Adjustment – White Balance ....................................................................... 36

9.3.1  User-specic Color Adjustment ...................................................................... 36

9.3.2 One Push White Balance ............................................................................... 37

9.4 Analog Controls ..................................................................................................... 37

9.4.1 Offset / Black Level ......................................................................................... 37

9.4.2 Gain ................................................................................................................ 38

9.5 Pixel Correction ..................................................................................................... 39

9.5.1 General information ........................................................................................ 39

9.5.2 Correction Algorithm ....................................................................................... 40

9.5.3 Defectpixellist ................................................................................................. 40

9.6 Process Interface .................................................................................................. 41

9.6.1 Digital IOs ....................................................................................................... 41

9.6.2 IO Circuits ....................................................................................................... 42

9.6.3 Trigger ............................................................................................................ 43

9.6.4 Trigger Source ................................................................................................ 43

9.6.5 Debouncer ...................................................................................................... 44

9.6.6 Flash Signal .................................................................................................... 44

9.6.7 Timers ............................................................................................................. 45

9.6.8 Frame counter ................................................................................................ 45

9.7 Sequencer ............................................................................................................. 46

9.7.1 General Information ........................................................................................ 46

9.7.2  Baumer Optronic Sequencer in Camera xml-le ............................................ 47

9.7.3 Examples ........................................................................................................ 47

9.7.4 Capability Characteristics of Baumer GAPI Sequencer Module .................... 48

9.7.5 Double Shutter ............................................................................................... 49

9.8 Device Reset ......................................................................................................... 49

9.9 User Sets .............................................................................................................. 50

9.10 Factory Settings .................................................................................................. 51

9.11 Timestamp ........................................................................................................... 51

10. Interface Functionalities ........................................................................................ 52

10.1 Device Information .............................................................................................. 52

10.2 Baumer Image Info Header (Chunk) ................................................................... 53

10.3 Message Channel ............................................................................................... 54

10.3.1 Event Generation ......................................................................................... 54

11. Start-Stop Behaviour ............................................................................................. 55

11.1 Start / Stop / Abort Acquisition (Camera)............................................................. 55

11.2 Start / Stop Interface ........................................................................................... 55

11.3 Acquisition Modes ............................................................................................... 55

11.3.1 Free Running ................................................................................................ 55

11.3.2 Trigger ........................................................................................................... 55

11.3.3 Sequencer .................................................................................................... 55

12. Cleaning .................................................................................................................. 56

13. Transport / Storage ................................................................................................ 56

14. Disposal .................................................................................................................. 56

5

15. Warranty Notes ....................................................................................................... 57

16. Support .................................................................................................................... 57

17. Conformity ..................................................................................................................

17.1 CE ...........................................................................................................................

17.2 RoHS ......................................................................................................................

6

General Information1.

Thank you for purchasing a camera from the Baumer range. This User's Guide describes
how to connect, set up and use the camera.

Read this manual carefully and observe the notes and safety instructions!

Target group for this User's Guide

This User's Guide is aimed at experienced users who want to integrate camera(s) into a
vision system.

Copyright

Any duplication or reprinting of this documentation, in whole or in part, and the reproduc-

tion of the illustrations even in modied form is permitted only with the written approval of 

Baumer. This document is subject to change without notice.

Classicationofthesafetyinstructions

In the User's Guide, the safety instructions are classied as follows:

Notice

Gives helpful notes on operation or other general recommendations.

Caution

Pi ctogram

Indicates a potentially dangerous situation. If the situation is not avoided,
slight or minor injury could result or the device may be damaged.

7

General safety instructions2.

Caution

Heat can damage the camera. Heat must be dissipated adequately to en­sure that the temperatures do not exceed the values (see Heat Transmis­sion).

As there are numerous options for installation, Baumer does not specify a

specic method for proper heat dissipation. 

Caution

Device heats up during operation.

Skin irritation possible.

Do not touch the camera during operation.

Caution

Observe precautions for handling electrostatically sensitive devices!

Intended Use3.

The camera is used to capture images that can then be transferred over a USB 3.0 inter­face to a PC.

Notice

Use the camera only for its intended purpose! For any use that is not described in the
technical documentation poses dangers and will void the warranty. The risk has to be
borne solely by the unit´s owner.

8

General Description4.

1

2

4

3

No. Description No. Description

1 Lens mount (C-Mount) 4 USB 3.0 port

2 LED

3 Digital IO

All VisiLine cameras with a USB 3.0 interface have the following features:

Very high image quality Low noise and structure-free image information ▪

Flexible image acquisition Industrially compliant process interface with ▪

parameter setting capability (trigger and ash)

Fast image transfer Reliable transmission at 5000 Mbit/sec according ▪

to USB 3.0 (v1.0) standard
Single cable solution for data and power ▪

▪ GenICam™ and USB3 Vision

TM

compliant

Perfect integration Flexible generic programming interface ( ▪ Baumer

GAPI) for all Baumer cameras
Powerful ▪ Software Development Kit (SDK) with

sample codes and help les for easy integration

Baumer Camera Explorer Test Tool for all camera ▪
functions
Camera features according to the SFNC (v2.0) ▪

▪ GenICam™ compliant XML le to show the 

camera features
Supplied with installation program including ▪
automatic camera recognition for easy commis­sioning

Compact design Light weight ▪

Flexible assembly ▪

Reliable operation State-of-the-art camera electronics and precision ▪

mechanics
Low power consumption and minimal heat genera- ▪
tion

9

Camera Models5.

Camera Type

Sensor

Size

Resolution

Full

Frames

[max. fps]

CCD Sensor (monochrome / color)

VLU-02M / VLU-02C 1/4" 656 x 490 160

VLU-12M / VLU-12C 1/3" 1288 x 960 42

CMOS Sensor (monochrome / color)

VLU-03M / VLU-03C 1/3" 640 x 480 376

Dimensions

C-Mount

8 - M3 depth 3

2 - M2 depth 3

Pixel 0,0

4 - M3 depth 3

8,7

18

11

3,5

26

14,2

48,3

9,8

33

33

26

12

3,5

6,75

26

26

26

3,5

◄Figure1

Baumer VLU camera

10

Installation6.

Caution

Observe precautions for handling electrostatically sensitive devices!

Lens mounting6.1

Notice

Ensure the sensor and lens are not contaminated with dust and airborne particles when
mounting the support or the lens to the device!

The following points are very important:

Install the camera in an environment that is as dust free as possible! ▪
Keep the dust cover (bag) on the camera for as long as possible! ▪
Hold the printer with the sensor downwards if the sensor is uncovered. ▪
Avoid contact with any of the camera's optical surfaces! ▪

Environmental Requirements6.2

Temperature

Storage temperature -10°C ... +70°C ( +14°F ... +158°F)

Operating temperature* see Heat Transmission

* If the ambient temperature exceeds the values listed in the table below, the camera must
be cooled. (see Heat Transmission)

Humidity

Storage and Operating Humidity 10% ... 90%

Non-condensing

Mechanical Tests6.2.1

Environmen­tal Testing

Standard Parameter

Vibration, sinu­sodial

IEC 60068-2-6 Search for Reso-

nance

10-2000 Hz

Amplitude under­neath crossover
frequencies

1.5 mm

Acceleration 1 g

Test duration 15 min

Vibration,
broad band

IEC 60068­2-64

Frequency range 20-1000 Hz

Acceleration 10 g

Displacement 5.7 mm

Test duration 300 min

Shock IEC 60068-

2-27

Puls time 11 ms / 6

ms

Acceleration 50 g / 100 g

Bump IEC60068-2-

29

Pulse Time 2 ms

Acceleration 80 g

11

Heat Transmission6.2.2

Caution

Heat can damage the camera. Heat must be dissipated adequately to en­sure that the temperature does not exceed the values in the table below.

As there are numerous possibilities for installation, Baumer do not speciy 
a specic method for proper heat dissipation, but suggest the following 
principles:

operate the cameras only in mounted condition ▪
mounting in combination with forced convection may provide proper heat ▪
dissipation

Caution

Device heats up during operation.

Skin irritation possible.

Do not touch the camera operation.

T

Measurement Point Maximum Temperature

T max. 50°C (122°F)

◄Figure2

Temperature measuring
point

12

7. Pin Assignment

7.1 USB 3.0 Interface

USB 3.0 Micro B

123 45 678 910

1 VBUS 6 MicB_SSTX-

2 D- 7 MicB_SSTX+

3 D+ 8 GND_DRAIN

4 ID 9 MicB_SSRX-

5 GND 10 MicB_SSRX+

7.2 Digital IOs

Digital IOs

(M8 / 8 pins / wire colors of the connecting cable)

8

5

7

3

1

4

2

6

1 OUT 3 white

5 IO Power VCC

grey

2 not connected

brown

6 OUT 1

pink

3 IN 1

green

7 not connected

blue

4 IO GND

yellow

8 OUT 2

red

IO Power VCC

4

6

5

I

OUT

RL *)

I

OUT

I

OUT

RL *)

R

L

*)

1

8

3

In 1

IO Ground

current limiter

cable termination

I

IN

Out 1

Out 2

Out

(Line2)

(Line1)

(Line3)

(Line0)

3

*) resistor must be used, I

Out

= 16 mA

by U

EXT

= 24 VDC recommended,
drawing shown above example
for using high active signal

13

7.2.1 LED Signalling

LED

Signal Meaning

LED

green USB 3.0 connection

yellow USB 2.0 connection

(settings possible, no frames)

Notice

Why can frames not be transferred over an USB 2.0 connection?

The camera needs to be supplied with more than 2.5W when transferring frames. With
an USB 2.0 connection maximally 2.5W are available. Therefore switching off of the
frame transfer is necessary. However, settings are still possible.

◄Figure3

LED position on Baumer
VLU camera.

14

8. ProductSpecications

8.1 Spectral Sensitivity for Baumer VLU Cameras

The following graphs show the spectral sensitivity characteristics of monochrome and
color matrix sensors for VLU cameras. The curves for the sensors do not take the char-

acteristics of lenses and light sources without lters into account.

Values relate to the respective technical data sheets for the sensors.

400 500 600 700 800 900 1000

0

0 2

0 4

0 6

0 8

1 0

Wave Length [nm]

Relative Response

VLU-02M

400 450 500 550 600 650 700

0

0 2

0 4

0 6

0 8

1 0

Wave Length [nm]

Relative Response

VLU-02C

350 450 550 650 750 850 950 1050

Wave Length [nm]

Quantum Efficiency [%]

VLU-03M

350 450 550 650 750 850 950 1050

Wave Length [nm]

Quantum Efficiency [%]

VLU-03C

400 500 600 700 800 900 1000

0

0 2

0 4

0 6

0 8

1 0

Wave Length [nm]

Relative Response

VLU-12M

400 450 500 550 600 650 700

0

0 2

0 4

0 6

0 8

1 0

Wave Length [nm]

Relative Response

VLU-12C

300 400 500 600 700 800 900

0

0 2

0 4

0 6

0 8

1 0

Wave Length [nm]

Relative Response

Filter glass

Figure4►

Spectral sensitivities for
Baumer cameras with

0.3 MP CCD sensors.

Figure5►

Spectral sensitivities for
Baumer cameras with

0.3 MP CMOS sensors.

Figure6►

Spectral sensitivities for
Baumer cameras with

1.2 MP CCD sensors.

Figure7►

Curve of the UV/IR

blocking lter for color 

cameras

15

8.2 Field of View Position

The gures  and table below show the typical  accuracy by assumption of the  root mean 
square value:

photosensitive
surface of the
sensor

front cover
glass

thickness:
1 ± 0.1 mm

cover glass
of sensor
thickness: D

optical path
c mount (17.526 mm)

± XM

± YM

± YR

± XR

± α

± Z

A

14,6

Camera

Type

± xM

[mm]

± yM

[mm]

± xR

[mm]

± YR

[mm]

± z

typ

[mm]

± α

typ

[°]

A

[mm]

D**

[mm]

VLU-02* 0.09 0.09 0.09 0.09 0.025 0.7 16.1 0.75

VLU-03* 0.07 0.07 0.07 0.07 0.025 1.23 17.54 0.45

VLU-12* 0.06 0.06 0.06 0.06 0.025 0.7 16.6 0.5

typical accuracy by assumption of the root mean square value
* C or M
** Dimension D in this table is from manufacturer datasheet (edition 06/2012)

16

8.3 Acquisition Modes and Timings

Image acquisition consists of two separate, successively processed components.

Exposing the pixels on the photosensitive surface of the sensor is only the rst part of the 
image acquisition process. Once the rst step is completed, the pixels are read out.

The exposure time (t

exposure

) can be adjusted by the user, however, the time needed for the

readout (t

readout

) is determined by the particular sensor and image format.

Baumer cameras can be operated in three different modes, Free Running Mode, Fixed­Frame-Rate Mode and Trigger Mode.

The cameras can be operated non-overlapped

1)

or overlapped, depending on the mode

used and the combination of exposure and readout time:

Non-overlapped Operation Overlapped Operation

Here, the time intervals are long enough
to process the exposure and readout suc­cessively.

In this operation mode, the exposure of a
frame (n+1) occurs during the readout of
frame (n).

Exposure

Readout

Exposure

Readout

8.3.1 Free Running Mode

In the "Free Running" mode, the camera records images permanently and transfers them
to the PC. To achieve the best results (with regard to the adjusted exposure time t

exposure

and image format), the camera is operated overlapped.

In case of exposure times equal to / less than the readout time (t

exposure

 ≤ t

readout

), the maxi­mum frame rate is provided for the image format used. For longer exposure times, the
frame rate of the camera is reduced.

Exposure

Readout

Flash

t

exposure(n)

t

flash(n)

t

flashdelay

t

flash(n+1)

t

readout(n+1)

t

readout(n)

t

exposure(n+1)

t

ash

= t

exposure

1)Non-overlapped means sequential.

Image parameters:

Offset
Gain

Mode

Partial Scan

Timings:

A - exposure time
frame (n) effective
B - image parameters
frame (n) effective
C - exposure time
frame (n+1) effective
D - image parameters
frame (n+1) effective

17

Fixed-Frame-Rate Mode8.3.2

With this feature, Baumer introduces a clever technique to the VLU camera series that

enables the user to predene a desired frame rate in continuous mode.

For this mode, the cameras are equipped with an internal clock generator that creates
trigger pulses.

Notice

Above a certain frame rate, skipping internal triggers becomes unavoidable. In general,
this depends on the combination of the adjusted frame rate, exposure and readout
times.

18

8.3.3 Trigger Mode

Image acquisition begins after a specied external event (trigger) occurs. Depending on
the interval of triggers used, the camera can operate either non-overlapped or overlapped
in this mode.

With regard to timings in the trigger mode, the following basic formulas need to be taken

into consideration:

Case Formula

t

exposure

< t

readout

(1) t

earliestpossibletrigger(n+1)

= t

readout(n)

- t

exposure(n+1)

(2) t

notready(n+1)

= t

exposure(n)

+ t

readout(n)

- t

exposure(n+1)

t

exposure

> t

readout

(3) t

earliestpossibletrigger(n+1)

= t

exposure(n)

(4) t

notready(n+1)

= t

exposure(n)

8.3.3.1 Overlapped Operation: t

exposure(n+2)

= t

exposure(n+1)

During overlapped operation, be mindful of the time interval during which the camera is
unable to process trigger signals (t

notready

) that occur. This interval occurs between two

exposures. When this processing time t

notready

has elapsed, the camera is able to react to

external events again.

Once t

notready

has elapsed, the timing of (E) depends on the readout time of the current

image (t

readout(n)

) and exposure time of the next image (t

exposure(n+1)

). It can be determined by

the formulas mentioned above (no. 1 or 3, dependant on the case).

In case of identical exposure times, t

notready

remains the same from acquisition to acquisi-

tion.

Exposure

Readout

t

exposure(n)

t

readout(n+1)

t

readout(n)

t

exposure(n+1)

t

triggerdelay

t

min

Trigger

Flash

t

flash(n)

t

flashdelay

t

flash(n+1)

TriggerReady

t

notready

Image parameters:

Offset
Gain

Mode

Partial Scan

Timings:

A - exposure time
frame (n) effective
B - image parameters
frame (n) effective
C - exposure time
frame (n+1) effective
D - image parameters
frame (n+1) effective
E - earliest possible trigger

19

8.3.3.2 Overlapped Operation: t

exposure(n+2)

> t

exposure(n+1)

If the exposure time (t

exposure

) is increased from the current acquisition to the next acquisi-

tion, the time the camera is unable to process occurring trigger signals (t

notready

) is scaled

down accordingly.

This can be simulated with the formulas mentioned above (no. 2 or 4, dependant on the
case).

Exposure

Readout

t

exposure(n)

t

readout(n+1)

t

readout(n)

t

exposure(n+1)

t

exposure(n+2)

t

triggerdelay

t

min

Trigger

Flash

t

flash(n)

t

flashdelay

t

flash(n+1)

TriggerReady

t

notready

Image parameters:

Offset
Gain

Mode

Partial Scan

Timings:

A - exposure time
frame (n) effective
B - image parameters
frame (n) effective
C - exposure time
frame (n+1) effective
D - image parameters
frame (n+1) effective
E - earliest possible trigger

20

8.3.3.3 Overlapped Operation: t

exposure(n+2)

< t

exposure(n+1)

If the exposure time (t

exposure

) is decreased from the current acquisition to the next acquisi-

tion, the time the camera is unable to process occurring trigger signals (t

notready

) is scaled

up accordingly.

If the t

exposure

is decreased to the extent that t

notready

exceeds the pause between two incom­ing trigger signals, the camera is unable to process this trigger and image acquisition will
not start (the trigger will be skipped).

Exposure

Readout

t

exposure(n)

t

readout(n+1)

t

readout(n)

t

exposure(n+1)

t

exposure(n+2

t

triggerdelay

t

min

Trigger

Flash

t

flash(n)

t

flashdelay

t

flash(n+1)

TriggerReady

t

notready

Notice

Above a certain frequency of trigger signal, skipping triggers becomes unavoidable. In
general, this frequency depends on the combination of exposure and readout times.

Image parameters:

Offset
Gain

Mode

Partial Scan

Timings:

A - exposure time
frame (n) effective
B - image parameters
frame (n) effective
C - exposure time
frame (n+1) effective
D - image parameters
frame (n+1) effective
E - earliest possible trigger
F - frame not started /
trigger skipped

21

8.3.3.4 Non-overlapped Operation

If the frequency of the trigger signal is set long enough that the image acquisitions (t

exposure

+ t

readout

) run successively, the camera operates non-overlapped.

Exposure

Readout

t

exposure(n)

t

readout(n+1)

t

readout(n)

t

exposure(n+1)

t

triggerdelay

t

min

Trigger

Flash

t

flash(n)

t

flashdelay

t

flash(n+1)

TriggerReady

t

notready

Image parameters:

Offset
Gain

Mode

Partial Scan

Timings:

A - exposure time
frame (n) effective
B - image parameters
frame (n) effective
C - exposure time
frame (n+1) effective
D - image parameters
frame (n+1) effective
E - earliest possible trigger

22

Advanced Timings for 8.3.4 USB 3.0 VisionTM Message Channel

The following charts show some timings for event signalling by the asynchronous mes­sage  channel.  Explanations  are  provided  for  vendor-specic  events  such  as  "Trigger­Ready", "TriggerSkipped", "TriggerOverlapped" and "ReadoutActive".

8.3.4.1 TriggerReady

This event signals whether the camera is able to process incoming trigger signals or not.

Exposure

Readout

t

exposure(n)

t

readout(n+1)

t

readout(n)

t

exposure(n+1)

Trigger

TriggerReady

Event: TriggerReady

t

notready

8.3.4.2 TriggerSkipped

If the camera is unable to process incoming trigger signals, meaning that the camera
should be triggered within the interval t

notready

, these triggers are skipped. On Baumer VLU

cameras, the user will be informed about this fact by way of the "TriggerSkipped" event.

Exposure

Readout

t

exposure(n)

t

readout(n+1)

t

readout(n)

t

exposure(n+1)

Trigger

TriggerReady

t

notready

TriggerSkipped

Event: TriggerSkipped

23

8.3.4.3 TriggerOverlapped

This signal is active for as long as the sensor is exposed and read out at the same time,
meaning that the camera is operated overlapped.

Exposure

Readout

t

exposure(n)

t

readout(n+1)

t

readout(n)

t

exposure(n+1)

Trigger

Trigger
Overlapped

Event: TriggerOverlapped

Once a valid trigger signal occurs outside of a readout, the "TriggerOverlapped" signal
changes to state low.

8.3.4.4 ReadoutActive

While the sensor is being read out, the camera signals this with "ReadoutActive".

Exposure

Readout

Event: ReadoutActive

t

exposure(n)

t

readout(n+1)

t

readout(n)

t

exposure(n+1)

Trigger

Readout
Active

24

8.4 Software

8.4.1 Baumer GAPI

Baumer GAPI stands for Baumer “Generic Application Programming Interface”. With this
API, Baumer provides an interface for optimal integration and control of Baumer cam­eras.

It provides interfaces to several programming languages, such as C, C++ and the .NET™
Framework on Windows

®

, meaning that other languages, such as e.g. C# or VB.NET can

also be used.

Baumer GAPI SDK higher than v2.2 supports USB3 Vision

TM

.

8.4.2 3rd Party Software

Strict compliance with the GenICam™ and USB3 VisionTM standards allows Baumer to
offer the use of 3rd Party software.

You can nd a current list of 3

rd

Party software that has been tested successfully in com­bination with Baumer cameras at http://www.baumer.com/de-en/products/identication-

image-processing/software-and-starter-kits/third-party-software/

25

C9. amera Functionalities

Image 9.1 Acquisition

9.1.1 Image Format

A digital camera usually delivers image data in at least one format - the native resolution
of the sensor. Baumer cameras are able to provide several image formats (depending on
the type of camera).

Compared with standard cameras, the image format on Baumer cameras includes not

only the resolution, but also a set of predened parameters.

These parameters are:

▪ Resolution (horizontal and vertical dimensions in pixels)
▪ Binning Mode

Camera Type

Full frame

Binning 2x2

Binning 1x2

Binning 2x1

Monochrome

VLU-02M ■ ■ ■ ■

VLU-03M ■ ■ ■ ■

VLU-12M ■ ■ ■ ■

Color

VLU-02C ■ ■ ■ ■

VLU-03C ■ ■ ■ ■

VLU-12C ■ ■ ■ ■

26

9.1.2 Pixel Format

On Baumer digital cameras, the pixel format depends on the selected image format.

Denitions9.1.2.1

RAW: Raw data format. Here, the data is stored without being processed.

Bayer: Raw data format of color sensors.

Color lters are placed on these sensors in a checkerboard pattern, generally 

in a 50% green, 25% red and 25% blue array.

Mono: Monochrome. The color range of mono images consists of shades of a sin-

gle color. In general, shades of gray or black-and-white are synonymous with
monochrome.

RGB: Color  model  in  which  all  detectable  colors  are  dened  by  three  coordinates, 

Red, Green and Blue.

Red

Green

Blue

Black

White

The three coordinates are displayed within the buffer in the order R, G, B.

BGR: Here, the color alignment mirrors RGB.

YUV: Color model, which is used in the PAL TV standard and in image compression.

In YUV, a high bandwidth luminance signal (Y: luma information) is transmitted 
together with two color difference signals with low bandwidth (U and V: chroma

information). U represents the difference between blue and luminance (U = B ­Y), V is the difference between red and luminance (V = R - Y). The third color,
green, does not need to be transmitted as its value can be calculated from the
other three values.

YUV 4:4:4 Here, each of the three components has the same sample rate.

There is therefore no sub-sampling in this case.

YUV 4:2:2 The chroma components are sampled at half the sample rate.

This reduces the necessary bandwidth to two-thirds (in relation to

4:4:4) and causes no, or low visual differences.

YUV 4:1:1 Here, the chroma components are sampled at a quarter of the

sample rate. This decreases the necessary bandwidth by half (in

relation to 4:4:4).

Figure8►

Sensor with Bayer
Pattern

Figure9►

RBG color space dis­played as color tube.

27

Pixel depth: In general,  pixel  depth denes  the  number of possible  different  values for 

each color channel. Mostly this will be 8 bit, which means 28 different "col­ors".

For RGB or BGR these 8 bits per channel equate to 24 bits overall.

Two bytes are needed to transmit more than 8 bits per pixel - even if the

second byte is not  completely  lled  with data.  In  order to  save bandwidth, 

packed formats have been added to Baumer VLU cameras. In these for-

mats, the unused bits of one pixel are lled with data from the next pixel.

8 bit:

Byte 1 Byte 2 Byte 3

12 bit:

Byte 1 Byte 2

unused bits

Packed:

Byte 1 Byte 2 Byte 3

Pixel 0Pixel 1

Pixel Formats on Baumer VLU Cameras9.1.2.2

Camera Type

Mono 8

Mono 12

Mono 12 Packed

Bayer RG 8

Bayer RG 12

RGB 8

BGR 8

YUV8_UYV

YUV422_8_UYVY

YUV411_8_UYYVYY

Monochrome

VLU-02M ■ ■ ■ □ □ □ □ □ □ □

VLU-03M ■ ■ ■ □ □ □ □ □ □ □

VLU-12M ■ ■ ■ □ □ □ □ □ □ □

Color

VLU-02C ■ □ □ ■ ■ ■ ■ ■ ■ ■

VLU-03C ■ □ □ ■ ■ ■ ■ ■ ■ ■

VLU-12C ■ □ □ ■ ■ ■ ■ ■ ■ ■

◄Figure10

Bit string of Mono 8 bit
and RGB 8 bit.

◄Figure11

Spreading of Mono 12
bit over two bytes.

◄Figure12

Spreading of two pix­els in Mono 12 bit over
three bytes (packed
mode).

28

9.1.3 Exposure Time

On exposure of the sensor, the inclination of photons produces a charge separation on
the semiconductors of the pixels. This results in a voltage difference, which is used for
signal extraction.

Light

Photon

Pixel

Charge Carrie

r

The signal strength is inuenced by the incoming amount of photons. It can be increased 

by increasing the exposure time (t

exposure

).

On Baumer VLU cameras, the exposure time can be set within the following ranges (in-

crements of 1μsec):

Camera Type t

exposure

min t

exposure

max

Monochrome

VLU-02M 4 μsec 60 sec

VLU-03M 4 μsec 60 sec

VLU-12M 4 μsec 60 sec

Color

VLU-02C 4 μsec 60 sec

VLU-03C 4 μsec 60 sec

VLU-12C 4 μsec 60 sec

Figure13►

Incidence of light causes
charge separation on
the semiconductors of
the sensor.

29

PRNU / DSNU Correction (FPN - Fixed Pattern Noise)9.1.4

Camera Type

PRNU / DSNU

correction

CCD (monochrome / color)

VLU-02M / VLU-02C □

VLU-12M / VLU12C □

CMOS (monochrome / color)

VLU-03M / VLU-03C ■

CMOS sensors exhibit  non-uniformities  that are  often called xed pattern  noise  (FPN). 
However, it is not actually noise, but rather a xed variation from pixel to pixel that can be

corrected. The advantage of using this correction is a more homogeneous picture which
may simplify image analysis. Variations of the dark signal from pixel to pixel are called
dark signal non-uniformity (DSNU) whereas photo response non-uniformity (PRNU) de­scribes variations in sensitivity. DSNU is corrected via an offset while PRNU is corrected
using a factor.

The correction is based on columns. It is important that the correction values are calcu-

lated for the sensor readout conguration used. During camera production, this is derived 

from the factory defaults. If other settings are used (e.g. different number of readout chan­nels), using this correction with the default data set may degrade the image quality. In this

case, the user may derive a specic data set for the setup used.

without PRNU / DSNU Correction
(Example image, PRNU / DSNU Correction can not
be disabled)

with PRNU / DSNU Correction

30

HDR (High Dynamic Range)9.1.5

Camera Type

HDR

CCD (monochrome / color)

VLU-02M / VLU-02C □

VLU-12M / VLU12C □

CMOS (monochrome / color)

VLUC-03M / VLU-03C ■

Alongside the standard linear response, the sensor also supports a special high dynamic
range mode (HDR) called piecewise linear response. With this mode, illuminated pixels
that reach a certain programmable voltage level are clipped. Darker pixels that do not
reach this threshold remain unchanged. The clipping can be adjusted twice within a single

exposure by conguring  the  respective  time slices  and clipping  voltage levels. See the 
gure below for details.

In this mode, the values for t

Expo0

, t

Expo1

, Pot0 and Pot1can be edited.

The value for t

Expo2

is calculated automatically within the camera. (t

Expo2

= t

exposure

- t

Expo0

-

t

Expo1

)

HDR Off HDR On

31

9.1.6 Look-Up-Table

The Look-Up-Table (LUT) is used on Baumer VLU monochrome and color cameras. It
contains 212 (4096) values for the available levels. These values can be adjusted by the
user.

9.1.7 Gamma Correction

With this feature, Baumer VLU cameras provide the option to compensate nonlinearity in
the perception of light by the human eye.

For this correction, the corrected pixel intensity (Y') is calculated using the original inten­sity of the sensor's pixel (Y

original

) and correction factor γ using the following formula (in an

oversimplied version):

Y' = Y

original

γ

On Baumer VLU cameras the correction factor γ is adjustable from 0.001 to 2.

The values of the calculated intensities are entered into the Look-Up-Table (see 9.1.5).
Previously existing values within the LUT will be overwritten.

Notice

If the LUT feature is disabled on the software side, the gamma correction feature is also
disabled.

H

E0

▲Figure14

Non-linear perception of
the human eye.
H - Perception of bright­ ness
E - Energy of light

32

Region of Interest (ROI)9.1.8

With the "Region of  Interest" (ROI)  function,  you can  predene  a so-called  Region  of 
Interest (ROI) or Partial Scan. This ROI is an area of pixels of the sensor. When an im­age is acquired, only the information about these pixels is transferred to the PC. Not all
lines of the sensor are read out, which therefore decreases the readout time (t

readout

). This

increases the frame rate.

This function is used when only a particular region of the eld of view is of interest. It is 

coupled with a reduction in resolution.

The ROI is specied by four values:

▪ Offset X  - x-coordinate of the rst relevant pixel
▪ Offset Y  - y-coordinate of the rst relevant pixel
▪ Size X - horizontal size of the ROI
▪ Size Y - vertical size of the ROI

Start ROI

End ROI

ROI Readout

In the illustration below, readout time would decrease to 40% of a full frame readout.

Readout lines

Figure15►

ROI: Parameters

Figure16►

Decrease in readout
time by using partial
scan.

33

Binning9.1.9

On digital  cameras, you can  nd several  operations  for progressing  sensitivity. One  of 

these is "Binning". Here, the charge carriers of neighboring pixels are aggregated. Thus
the progression is greatly increased by the amount of binned pixels. By using this opera­tion, the progression in sensitivity is coupled with a reduction in resolution.

Baumer cameras support three types of binning - vertical, horizontal and bidirectional.

In unidirectional binning, vertically or horizontally neighboring pixels are aggregated and
reported to the software as a single "superpixel".

In bidirectional binning, a square of neighboring pixels is aggregated.

Binning Illustration Example

without

1x2

2x1

2x2

◄Figure17

Full frame image, no
binning of pixels.

◄Figure18

Vertical binning causes
a doubly bright ,vertical­ly compressed image.

◄Figure19

Horizontal binning
causes a doubly bright,
horizontally compressed
image.

◄Figure20

Bidirectional binning
causes both a hori­zontally and vertically
compressed image with
quadruple brightness.

34

Brightness Correction (9.1.10 Binning Correction)

Aggregation of charge carriers may cause an overload. Binning correction was introduced

to prevent this. Here, three binning modes need to be considered separately:

Binning Realization

1x2 1x2 binning is performed within the sensor, binning correction also takes

place here. A possible overload is prevented by halving the exposure time.

2x1 2x1 binning takes place within the FPGA of the camera. The binning cor-

rection is realized by aggregating the charge quantities, and then halving
this sum.

2x2 2x2 binning is a combination of the above versions.

Charge quantity

Binning 2x2

Super pixel

To tal charge
quantity of the
4 aggregated
pixels

Figure21►

Aggregation of charge
carriers from four pixels
in bidirectional binning.

35

Flip Image9.1.11

The  Flip  Image function  lets you  ip  the captured  images horizontally  and/or  vertically 

before they are transmitted from the camera.

Notice

Any dened ROI will also be ipped.

Camera Type

Horizontal

Vertical

VLU-02M / VLU-02C ■ □

VLU-12M / VLU-12C ■ □

VLU-03M / VLU-03C ■ ■

Normal Flip vertical

(Reverse Y)

Normal Flip horizontal

(Reverse X)

Normal Flip horizontal and vertical

(Reverse X, Y)

◄Figure22

Flip image vertically

◄Figure23

Flip image horizontally

◄Figure24

Flip image horizontally
and vertically

36

9.2 Color Processing

Baumer color cameras are balanced to a color temperature of 5000 K.

Oversimplied, color processing is realized by 4 modules.

Camera

Module

Bayer

Processor

Color

Transfor

mation

RGB

r

g

b

r'

g'

b'

r''

b''

g''

Y

White balance

The sensor's r (red), g (green) and b (blue) color signals are amplied in total and digitized 

within the camera module.

Within the Bayer processor, the raw signals r', g' and b' are amplied using independent 
factors for each color channel. Then, the missing color values are interpolated, which re­sults in new color values (r'', g'', b''). The luminance signal Y is also generated.

The next step is color transformation. Here, the previously generated color signals r'', g''
and b'' are converted to the chroma signals U and V, which conform to the standard. Then,
these signals are transformed into the desired output format. The following steps are then

processed simultaneously:

Transformation to RGB ▪ or YUV color space

▪ External color adjustment

Color ▪ adjustment as a physical balance of the spectral sensitivities

A sub-sampling of the chroma signals can be carried out to reduce the data rate of YUV

signals. Here, the following items can be customized to the desired output format:

Order of data output ▪
Sub-sampling of the chroma components to ▪ YUV 4:2:2 or YUV 4:1:1
Data rate is limited to 8 bits ▪

9.3 Color Adjustment – White Balance

The white balance is used to sensitize the camera to the color temperature of the light at
the pickup location.

This feature is available on all color cameras in the Baumer VLU series, and takes place
within the Bayer processor.

White balance means independent adjustment of the three color channels, red, green and
blue by using a correction factor for each channel.

User-specic9.3.1 Color Adjustment

The user-specic  color  adjustment  in Baumer color cameras means you can adjust the 
correction factors for each color gain. This way, you can adjust the amplication of each

color channel exactly to suit your needs. The correction factors for the color gains range
from 1 to 4.

non-adjusted

histogramm

histogramm after

user-specific

color adjustment

Figure25►

Color processing mod­ules of Baumer color
cameras.

Figure26►

Examples of histo­grams for a non-ad­justed image and for
an image after user-

specic  white  balance 

adjustment.

37

One Push 9.3.2 White Balance

Here, the three color spectrums are balanced to a single white point. The correction fac­tors of the color gains are determined by the camera (one time).

non-adjusted

histogramm

histogramm after

„one push“ white

balance

9.4 Analog Controls

9.4.1 Offset / Black Level

CCD Sensor

On Baumer VLU cameras with CCD sensors, the offset (or black level) is adjustable from
0 to 255 LSB (relating to 12 bit).

Camera Type Increments of 1 LSB

Relating to

Monochrome

VLU-02M 12 bit

VLU-12M 12 bit

Color

VLU-02C 12 bit

VLU-12C 12 bit

CMOS Sensor

On Baumer VLU cameras with CMOS sensors, the offset (or black level) is adjustable
from 0 to 255 LSB (relating to 12 bit).

Camera Type Increments of 1 LSB

Relating to

Monochrome

VLU-03M 12 bit

Color

VLU-03C 12 bit

◄Figure27

Examples of histograms
for a non-adjusted im­age and for an image
after "one push" white
balance adjustment.

38

9.4.2 Gain

In industrial environments, motion blur is unacceptable. Therefore, exposure times are
limited. However, this causes low output signals from the camera and results in dark im-

ages. To solve this issue, the signals can be amplied by a user-dened gain factor within 

the camera. This gain factor is adjustable.

Notice

Increasing the gain factor causes an increase in image noise.

CCD Sensor

Camera Type Gain factor [db]

Monochrome

VLU-02M 0...29.5

VLU-12M 0...29.5

Color

VLU-02C 0...29.5

VLU-12M 0...29.5

CMOS Sensor

Camera Type Gain factor [db]

Monochrome

VLU-03M 0...18

Color

VLU-03C 0...18

39

Pixel Correction9.5

General information9.5.1

There is a certain probability of abnormal pixels - so-called defect pixels - occurring for
sensors from all manufacturers. The charge quantity on these pixels is not linearly depen­dent on the exposure time.

The occurrence of these defect pixels is unavoidable and intrinsic to the manufacturing
and aging process of the sensors.

The operation of the camera is not affected by these pixels. They only appear as brighter
(warm pixel) or darker (cold pixel) spots on the recorded image.

Warm Pixel

Cold Pixel

Charge quantity

„Normal Pixel“

Charge quantity
„Cold Pixel“

Charge quantity
„Warm Pixel“

◄Figure28

Distinction of "hot" and
"cold" pixels within the
recorded image.

◄Figure29

Charge quantity of "hot"
and "cold" pixels com­pared with "normal"
pixels.

40

Correction Algorithm9.5.2

On cameras in the Baumer VLU series, the problem of defect pixels is solved as follows:

Possible defect pixels are identied during the camera's production process.  ▪

The coordinates of these pixels are stored in the factory settings of the camera. ▪

Once the sensor ▪ readout is completed, correction takes place:

Before any other processing, the values of the neighboring pixels on the left and the ▪

right side of the defect pixels are read out. (within the same Bayer phase for color)

Then, the average value of ▪ these 2 pixels is determined to correct the rst defect 

pixel

Finally, the value of the second defect pixel is corrected by using the previously ▪

corrected pixel and the pixel on the other side of the defect pixel.

The correction process is able to correct up to two neighboring defect pixels. ▪

Defect Pixels

Average Value

Corrected Pixels

9.5.3 Defectpixellist

As stated previously, this list is determined within the production process of Baumer cam­eras and stored in the factory settings.

Additional hot or cold pixels can develop during the lifecycle of a camera. In this case,
Baumer gives you the option to add their coordinates to the defectpixellist.

You can determine the coordinates

1)

of the affected pixels and add them to the list. Once
the defectpixellist is stored in a user set, pixel correction is carried out for all coordinates
on the defectpixellist.

1)  Position in relation to Full Frame Format (Raw Data Format / No ipping).

41

9.6 Process Interface

9.6.1 Digital IOs

UserDenableInputs9.6.1.1

The wiring of these input connectors is left to the user.

Sole exception is the compliance with predetermined high and low levels (0 .. 4,5V low,
11 .. 30V high).

The dened signals will have no direct effect, but can be analyzed and processed on the 

software side and used for controlling the camera.

The employment of a so called "IO matrix" offers the possibility of selecting the signal and
the state to be processed.

On the software side the input signals are named "Trigger", "Timer" and "LineOut 1..3".

(Input) Line 1

Trigger
Timer

LineOut 1 (Output)
LineOut 2 (Output)
LineOut 3 (Output)

state high

state low

IO Matrix

state selection

(inverter)

signal selection

(software side)

◄Figure30

IO matrix of the
Baumer VLU on the in­put side.

42

Congurable9.6.1.2 Outputs

With this feature, Baumer offers the possibility of wiring the output connectors to internal
signals, which are controlled on the software side.

Hereby on VisiLine

®

cameras, the output connector can be wired to one of provided inter-

nal signal:  "Off", "ExposureActive", "Line 0",  "Timer 1 …  3",  "ReadoutActive", "User0 … 

2", "TriggerReady", "TriggerOverlapped", "TriggerSkipped", "Sequencer Output 0 ... 2".
Beside this, the output can be disabled.

(Output) Line 1

state high

state low

(Output) Line 2

state high

state low

(Output) Line 3

state high

state low

IO Matrix

state selection

(inverter)

signal selection

(software side)

Line0 (Input)
Line1 (Input)
Line2 (Input)
O

Tr iggerReady
Tr iggerOverlapped
Tr iggerSkipped
ExposureActive
ReadoutActive

UserOutput0
UserOutput1
UserOutput2
Timer1Active
Timer2Active
Timer3Active
SequencerOutput0
SequencerOutput1
SequencerOutput2

User defined Signals nternal Signals

Loopthroughed

Signals

9.6.2 IO Circuits

Notice

Low Active: At this wiring, only one consumer can be connected. When all Output pins 
(1, 2, 3) connected to IO_GND, then current ows through the resistor as soon as one

Output is switched. If only one output connected to IO_GND, then this one is only us­able.

The other three outputs are not usable and may not be connected (e.g. IO Power V

CC

)!

IO Power VCC

4

6

5

I

OUT

RL *)

I

OUT

I

OUT

RL *)

R

L

*)

1

8

3

In 1

IO Ground

curent limi ter

cable term na ion

I

IN

Out 1

Out 2

Out

(Line2)

(Line1)

(Line3)

(Line0)

3

*) resistor must be used, I

Out

= 16 mA

by U

EXT

= 24 VDC recommended,
drawing shown above example
for using high active signal

Figure31►

IO matrix of the
Baumer VLU on the out­put side.

43

9.6.3 Trigger

Trigger signals are used to synchronize the camera exposure and a machine cycle or, in
case of a software trigger, to take images at predened time intervals.

Trigger (valid)

Exposure

Readout

Time

A

B

C

Different trigger sources can be used here.

9.6.4 Trigger Source

p

h

o

t

o

e

l

e

c

t

r

i

c

s

e

n

s

o

r

t

r

i

g

g

e

r

s

i

g

n

a

l

p

r

o

g

r

a

m

m

a

b

l

e

l

o

g

i

c

c

o

n

t

r

o

l

e

r

o

t

h

e

r

s

s

o

f

t

w

a

r

e

t

r

i

g

g

e

r

H

a

r

d

w

a

r

e

t

r

i

g

g

e

r

Each trigger source must be activated separately. When the trigger mode is activated, the
hardware trigger is activated by default.

▲Figure32

Trigger signal, valid for
Baumer cameras.

high

low

U

t0

4.5V

11V

30V

t

start active
trigger

◄Figure33

Camera in trigger

mode:

A - Trigger delay
B - Exposure time
C - Readout time

Trigger Delay:

The trigger delay is a
exible user-dened delay
between the given trigger
impulse and the image cap­ture. The delay time can
be set between 0.0 μsec
and 2.0 sec in increments
of 1 μsec. Where there are
multiple triggers during the
delay, the triggers will also
be stored and delayed. The
buffer is able to store up to
512 trigger
signals during the delay.

Your benets:

No need for an external ▪

trigger sensor to be perfect-

ly aligned

Different objects can be ▪

captured without hardware

changes

◄Figure34

Examples of possible
trigger sources.

44

9.6.5 Debouncer

The basic idea behind this feature was to separate interfering signals (short peaks) from
valid square wave signals, which can be important in industrial environments. Debouncing

means that invalid signals are ltered out, and signals lasting longer than a user-dened 

testing time t

DebounceHigh

will be recognized and routed to the camera to induce a trigger.

In order to detect the end of a valid signal and lter out possible jitters within the signal, 

a second testing time t

DebounceLow

was introduced. The timing for this can also be adjusted

by the user. If the signal value falls to state low and does not rise within t

DebounceLow

, this is

recognized as the end of the signal.

The debouncing times t

DebounceHigh

and t

DebounceLow

are adjustable from 0 to 5 msec in incre-

ments of 1 μsec.

low

high

U

t0

4.5V

11V

30V

low

high

U

t0

4.5V

11V

30V

t

∆t

1

∆tx high time of the signal
t

DebounceHigh

user defined debouncer delay for state high

t

DebounceLow

user defined debouncer delay for state low

t

DebounceHigh

∆t

2

∆t3∆t4∆t

5

∆t

6

t

DebounceLow

Incoming signals
(valid and invalid)

Debouncer

Filtered signal

9.6.6 Flash Signal

This signal is managed by exposure of the sensor.

Furthermore, the falling edge of the ash output signal can be used to trigger a movement
of the inspected objects. For this reason, the span time used for the sensor readout t

readout

can be used in industrial environments.

Debouncer:

Please note that the edges
of valid trigger signals are
shifted by t

DebounceHigh

and

t

DebounceLow

!

Depending on these
two timings, the trigger
signal may be temporally
stretched or compressed.

45

Timers9.6.7

Timers were introduced for advanced control of internal camera signals.

For example,  using a timer allows you  to control the ash signal  in such a way that the 
illumination does  not start synchronized to the sensor  exposure but rather a predened

interval earlier.

On Baumer VLU cameras, the timer conguration includes four components:

Exposure

Timer

t

exposure

t

triggerdelay

Trigger

t

TimerDuration

t

TimerDelay

Component Description

TimerTriggerSource This feature provides a source selection for each timer.

TimerTriggerActiva­tion

This feature selects the part of the trigger signal (edges or
states) that activates the timer.

TimerDelay This feature represents the interval between the incoming trig-

ger signal and the start of the timer.

TimerDuration This feature is used to adjust the activation time of the timer.

Flash Delay9.6.7.1

As previously stated, the timer feature can be used to start the connected illumination
earlier than the sensor exposure.

This implies a timer conguration as follows:

The ash output must be wired to the selected internal timer signal. ▪

The trigger source and trigger activation for the timer need to be the same as for the ▪
sensor exposure.
The TimerDelay feature (t ▪

TimerDelay

) needs to be set to a lower value than the trigger

delay (t

triggerdelay

).

The duration (t ▪

TimerDuration

) of the timer signal should last until the exposure of the sensor

is completed. This can be realized using the following formula:

t

TimerDuration

= (t

triggerdelay

– t

TimerDelay

) + t

exposure

9.6.8 Frame counter

The frame counter is part of the Baumer Image Info Header and is supplied with every im­age, if chunk mode is activated. It is generated by hardware and can be used to verify that
each of the camera's images is transmitted to the PC and received in the right order.

◄Figure35

Poss ble timer con-

guration  on  a  Baumer 

VLU.

46

9.7 Sequencer

General Information9.7.1

A sequencer is used for the automated control of series of images using different sets of
parameters.

m

o

z

The gure above shows the fundamental structure of the sequencer module.

A sequence (o) is dened as a complete pass through all sets of parameters. 

The loop counter (m) represents the number of sequence repetitions.

The repeat counter (n) is used to control the amount of images taken with the respective
sets of parameters.

The start of the sequencer can be initiated directly (free running) or via an external event
(trigger).

The additional frame counter (z) is used to create a semi-automated sequencer. It is ab­solutely independent from the other three counters, and used to determine the number of
frames per external trigger event.

The following timeline displays the temporal course of a sequence with:

n = 5 repetitions per set of parameters ▪
o = 3 sets of parameters (A,B and C) ▪
m = 1 sequence and ▪
z = 2 frames per ▪ trigger

t

n = 1

n = 2

n = 3

n = 4

n = 5

n = 1

n = 2

n = 3

n = 1n = 2

ABC

z = 2z = 2z = 2z = 2z = 2

Figure36►

Flow chart of

sequencer.
m - number of loop
passes
n - number of set
repetitions
o - number of
sets of parameters
z - number of frames
per trigger

Sequencer Parameter:

The mentioned sets of
parameters include the
following:

Exposure time ▪

Gain factor ▪

Output line ▪

Origin of ROI (Offset X, Y) ▪

Figure37►

Timeline for a single
sequence

47

Baumer Optronic 9.7.2 Sequencer in Camera xml-le

The Baumer Optronic sequencer is described in the category

“BOSequencer”

by the fol-

lowing features:

<Category Name="BOSequencer" NameSpace="Custom">

<pFeature>BoSequencerEnable</pFeature>

Enable / Disable

<pFeature>BoSequencerStart</pFeature>

Start / Stop

<pFeature>BoSequencerRunOnce</pFeature>

Run Once / Cycle

<pFeature>BoSequencerFreeRun</pFeature>

Free Running / Trigger

<pFeature>BoSequencerSetSelector</pFeature>

Congure set of parameters

<pFeature>BoSequencerLoops</pFeature>

Number of sequences (m)

<pFeature>BoSequencerSetRepeats</pFeature>

Number of repetitions (n)

<pFeature>BoSequencerFramesPerTrigger</pFeature>

Number of frames per
trigger (z)

<pFeature>BoSequencerExposure</pFeature>

Parameter exposure

<pFeature>BoSequencerGain</pFeature>

Parameter gain

</Category>

9.7.3 Examples

9.7.3.1 Sequencer without Machine Cycle

Sequencer

Start

A

A

B

B

C

C

The gure  above  shows an example for a fully automated  sequencer  with three sets of 

parameters (A,B and C). Here, the repeat counter (n) is set to 5 and the loop counter (m)
has a value of 2.

When the sequencer is started, with or without an external event, the camera will record 5
images successively in each case, using the sets of parameters A, B and C (which consti­tutes a sequence). After that, the sequence is started again, then the sequencer stops - in
this case the parameters are maintained.

◄Figure38

Example using a fully
automated sequencer.

48

9.7.3.2 Sequencer Controlled by Machine Steps (trigger)

A

A

B

B

C

C

Trigger

Sequencer

Start

The gure above shows an example for a semi-automated sequencer with three sets of 

parameters (A,B and C) from the previous example. The frame counter (z) is set to 2. This
means the camera records two pictures after an incoming trigger signal.

Capability Characteristics of 9.7.4 Baumer GAPI Sequencer Module

up to 128 sets of parameters ▪
up to 65536 loop passes ▪
up to 65536 repetitions of sets of parameters ▪
up to 65536 images per ▪ trigger event
free running mode without initial ▪ trigger

Figure39►

Example using a semi-

automated sequencer.

49

9.7.5 Double Shutter

This feature gives you the option to capture two images within a very short period of time.

Depending on the application, this is performed in conjunction with a ash unit. The rst 

exposure time (t

exposure

) is arbitrary and accompanied by the rst ash. The second expo-

sure time must be equal to, or longer than the readout time (t

readout

) of the sensor. The

pixels of the sensor are therefore receptive again shortly after the rst exposure. In order 

to realize the second short exposure time without an overrun of the sensor, a second short
ash must be used, and any subsequent extraneous light prevented.

Trigger

Prevent Light

Exposure

Readout

Flash

On Baumer VLU cameras, this feature is realized within the sequencer.

In order to generate this sequence, the sequencer must be congured as follows:

Parameter Setting:

Sequencer Run Mode Once by Trigger

Sets of parameters (o) 2

Loops (m) 1

Repeats (n) 1

Frames Per Trigger (z) 2

Device Reset9.8

The Device Reset feature corresponds with the turn off and turn on of the camera. The
camera starts up again with the adjusted User Set.

It is therefore no longer necessary to interrupt the power supply.

◄Figure40

Example of a double
shutter.

50

9.9 User Sets

Four user sets (0-3) are available for the Baumer cameras in the VLU series. User set 0

is the default set and contains the factory settings. User sets 1 to 3 are user-specic and 
can contain any user-denable parameters (see table below).

These user sets are stored within the camera and can be loaded, saved and transferred
to other cameras in the VLU series.

By using a so-called "user set default selector", one of the four possible user sets can
be selected as the default, which means that the camera starts up with these adjusted
parameters.

Parameter

AcquisitionStart FrameCounter

AcquisitionStop ReadOutBuffering

AcquisitionAbort LineInverter

AcquisitionFrameRate LineSource

TriggerMode UserOutputValue

TriggerSource UserOutputValueAll

TriggerActivation LineDebouncerHighTimeAbs

TriggerDelay LineDebouncerLowTimeAbs

ExposureMode EventNotication

ExposureTime HDREnable

AcquisitionFrameRateEnable HDRPotentialAbs

ReadoutMode HDRExposureRatio

Gain Width

Gamma Height

BalanceWhiteAuto OffsetX

BlackLevel OffsetY

BrightnessCorrection BinningHorizontal

BoSequencerEnable BinningVertical

BoSequencerExposure ReverseX

BoSequencerFramesPerTrigger ReverseY

BoSequencerGain PixelFormat

BoSequencerIOStatus TestImageSelector

BoSequencerLoops TestPattern

BoSequencerMode LUTEnable

BoSequencerOffsetX LUTValue

BoSequencerOffsetY DefectPixelCorrection

Gamma FixedPatternNoiseCorrection

BoSequencerSetNumberOfSets TxRetryCount

BoSequencerSetRepeats RxRetryCount

BoSequencerStart TxCommandoLength

ChunkModeActive RxAcknowledgeLength

ChunkEnable Baudrate

TimerDuration TxByteDelay

TimerDelay TxMessageDelay

TimerTriggerSource RxSynchronizationDelay

TimerTriggerActivation

51

9.10 Factory Settings

The factory settings are stored in "user set 0", the default user set. This is the only user
set that cannot be edited.

9.11 Timestamp

The timestamp is part of the USB 3.0 VisionTM standard. It is 64 bits long and denoted in
nanoseconds. Any image or event includes its corresponding timestamp.

The timestamp is not resettable with a function. At power on or reset, the timestamp starts
running from zero.

1122354

1122454

1122554

1122754

1123154

1123354

1122654

1123054

1123254

◄Figure41

Timestamps of recorded
images.

52

10. Interface Functionalities

10.1 Device Information

This information on the device is part of the camera's USB descriptor.

Included information:

Product ID (PID) ▪
Vendor ID (VID) ▪

Model Name Baumer USB Vendor ID

[Hexadecimal]

Baumer USB Product ID

[Hexadecimal]

VLU-02M 2825 010A

VLU-02C 2825 010B

VLU-03M 2825 0122

VLU-03C 2825 0123

VLU-12M 2825 010C

VLU-12C 2825 010D

General Unique Identier (GUID) ▪
Device vendor name (Manufacturer) ▪
Serial number (iSerialNumber) ▪

53

Baumer Image Info Header (Chunk)10.2

The Baumer Image Info Header is a data packet that is generated by the camera and
integrated into the Payload (every image), if chunk mode is activated.

This integrated data packet contains different settings for the image. Baumer GAPI can
read the Image Info Header (Chunk). Third party software that supports chunk mode can

read the features in the table below. These settings are (not exhaustive):

Feature Description

ChunkOffsetX Horizontal offset from the origin to the area of interest (in

pixels).

ChunkOffsetY Vertical offset from the origin to the area of interest

(in pixels).

ChunkWidth Returns the width of the image included in the payload.

ChunkHeight Returns the height of the image included in the payload.

ChunkPixelFormat Returns the pixel format of the image included in the pay-

load.

ChunkTimestamp Returns the Timestamp of the image included in the pay-

load at the time of the FrameStart internal event.

ChunkExposureTime Returns the exposure time used to capture the image.

ChunkGainSelector Selects which Gain to retrieve data from.

ChunkGain Returns the gain used to capture the image.

ChunkFrameID Returns  the  unique  Identier  of  the  frame  (or  image) 

included in the payload.

ChunkBinningHorizontal Number of horizontal photo-sensitive cells to combine

together.

ChunkBinningVertical Number of vertical photo-sensitive cells to combine

together.

◄Figure42

Location of the Baumer
Image Info Header

54

10.3 Message Channel

The asynchronous message channel is described in the USB 3.0 VisionTM standard and
allows you to signal events. There is a timestamp (64 bits) for each announced event,
which contains the accurate time at which the event occurred.

Each event can be activated and deactivated separately.

10.3.1 Event Generation

Event Description

GenICam™

ExposureStart Exposure started

ExposureEnd Exposure ended

FrameStart Acquisition of a frame started

FrameEnd Acquisition of a frame ended

Line0Rising Rising edge detected on IO-Line 0

Line0Falling Falling edge detected on IO-Line 0

Line1Rising Rising edge detected on IO-Line 1

Line1Falling Falling edge detected on IO-Line 1

Line2Rising Rising edge detected on IO-Line 2

Line2Falling Falling edge detected on IO-Line 2

Line3Rising Rising edge detected on IO-Line 3

Line3Falling Falling edge detected on IO-Line 3

Vendor-specic

EventDiscarded Event discarded

EventLost Event occurred but not analyzed

TriggerReady t

notready

elapsed, camera is able to

process incoming trigger

TriggerOverlapped Overlapped Mode detected

TriggerSkipped Camera over-triggered

55

11. Start-Stop Behaviour

Start / Stop / Abort 11.1 Acquisition (Camera)

Once image acquisition is started, three steps are processed within the camera:

Determination of the current set of image parameters ▪

▪ Exposure of the sensor

Readout of the sensor. ▪

Afterwards, this process is repeated until the camera is stopped.

Stopping the acquisition means that the process mentioned above is aborted. If the stop
signal occurs within a readout, the current readout will be completed before the camera is
stopped. If the stop signal occurs during an exposure, this will be aborted.

Abort Acquisition

The acquisition abort process is a special case where the current acquisition is stopped.

When an exposure is running, the exposure is aborted immediately and the image is not
read out.

Start / Stop 11.2 Interface

Transmission of image data from the camera to the PC will not proceed until the interface
is started. If image acquisition is started before the interface is activated, the recorded
images are lost.

If the interface is stopped during a transmission, this is aborted immediately.

11.3 Acquisition Modes

In general, three acquisition modes are available for the cameras in the Baumer VLU
series.

Free Running11.3.1

Free running means the camera records images continuously without external events.

11.3.2 Trigger

The basic idea behind the trigger mode is the synchronization of cameras with machine
cycles. Trigger mode means that image recording is not continuous, but rather triggered
by external events.

11.3.3 Sequencer

A sequencer is used for the automated control of series of images, using different settings
for exposure time and gain.

56

Cleaning12.

Cover glass

Notice

The sensor is mounted dust-proof. Remove of the cover glass for cleaning is not neces­sary.

Avoid cleaning the cover glass of the sensor glass if possible. To prevent dust, follow the
instructions under "Install lens".

If you must clean it, use compressed air or a soft, lint free cloth dampened with a small
quantity of pure alcohol.

Housing

Caution!

volatile
solvents

Volatile solvents for cleaning.
Volatile solvents damage the surface of the camera.
Never use volatile solvents (benzine, thinner) for cleaning!

To clean the surface of the camera housing, use a soft, dry cloth. To remove persistent
stains, use a soft cloth dampened with a small quantity of neutral detergent, then wipe
dry.

Transport / Storage13.

Notice

Transport the camera only in its original packaging. When the camera is not installed,
store it in its original packaging.

Storage Environment

Storage temperature -10°C ... +70°C ( +14°F ... +158°F)

Storage Humidity 10% ... 90% non condensing

Disposal14.

Do not dispose of outdated products with electrical or electronic circuits in
your normal domestic waste, but rather according to your national law and
the directives 2002/96/EC and 2006/66/EC for recycling electronic waste.

The proper disposal of obsolete equipment will help to save valuable
resources and prevent possible adverse effects on human health and the
environment.

Returning the packaging to the material cycle helps conserve raw materials
and reduces the production of waste. When no longer required, dispose of
the packaging materials in accordance with the local regulations in force.

Keep the original packaging during the warranty period in order to be able
to pack the device properly in the event of a warranty claim.

57

Warranty Notes15.

Notice

If it is obvious that the device is / was dismantled, reworked or repaired by anyone other
than Baumer technicians, Baumer Optronic will not take any responsibility for the sub­sequent performance and quality of the device!

Support16.

If you have any problems with the camera, feel free to contact our support.

Worldwide

Baumer Optronic GmbH

Badstrasse 30
DE-01454 Radeberg, Germany

Tel: [phone]

Email:     [e-mail]

Website:   www.baumer.com

58

Conformity17.

Cameras of the Baumer VLU family comply with:

CE ▪
RoHS ▪

CE17.1

We declare, under our sole responsibility, that the previously described Baumer VLU cam­eras conform with the directives of the CE.

RoHS17.2

All VLU cameras comply with the recommendation of the European Union concerning
RoHS Rules.

59

Baumer Optronic GmbH

Badstrasse 30
DE-01454 Radeberg, Germany
Phone [phone] · Fax [phone]
[e-mail] · www.baumer.com

Technical data has been fully checked, but accuracy of printed matter not guaranteed.

Subject to change without notice. Printed in Germany.