Philips Optimus Velara User manual

PHILIPS MEDICAL SYSTEMS DMC imaging_plates-velara.doc Oct – 17 - 2003 page 1-1

Computed Radiography, e.g. PCR or other imaging plates

Dose Rate Control setting Velara

Instead of programming IMAGING PLATE for Screens and IMAGING PLATES for Films in a later release of Velara one can select any of the following screens since they have the same kV characteristic (for a 400 speed system):

AGFA MR 400 KODAK X-OMAT.Rapid MAVIG SE-4 MCI OPTON.R.BlueFast REGO NP 400

For the film program :

X-CONSTANT RLF=1

Abbreviation: Any name up to six characters can be given. The abbreviation name should indicate the

programmed speed type if different speeds shall be used with the same imaging plates.

Dose of FSC [µGy]: Use K

explanation this page. The value can be adapted to the local "density taste".

Formula to determine the speed = S of a film-screen-combination:

K0 1000 µGy >> use speed as !! S = speed must not be mixed up !! S = ------- = --------------------------- >> abbreviation !! with S = sensitivity PCR !! K

is a constant with a value of 1000 µGy.

is a variable value principally representing a switch off dose to obtain a density of 1.0 above base and

If e.g. Ks = 5 µGy (like the example of the previous page)

1000 µGy S = = 200 5 µGy

Range of speed values S within the standard speed class SC systems:

More information, e.g. for films and screens not appearing in the selection list during programming, are available in booklet "Radiographic screens and films", manual order No. 4512 980 50592.

Dose of FSC [µGy]: >> name

fog, (normal films determined by the manufacturer of a film-screen system for defined processing conditions which are different in a computed RAD system). Can be adapted to the local "density taste"

only valid for film-screen-combinations for an optical density of 1.0

Speed class SC

Standard

dose / exposure [µGy]

Standard class SC

Speed value S

Range

6 167 5 - 9 12 83 10 - 18 25 40 20 - 36 50 20 40 - 71

100 10 80 - 140 200 5 160 - 280

400 2.5 320 - 560 800 1.25 630 – 1100 1600 0.625 1250 – 2200