SU1498201A1 - Analogue-computational tomograph - Google Patents

Abstract

The invention relates to the radiation monitoring of objects by analog-computed tomography. The purpose of the invention is to increase accuracy and sensitivity. For this purpose, a set of latent projection images, which appear as a beam of UV source 8, are formed on a plate made of radioluminescent glass and are read by a scanning photo detector 9. The image is projected by a computer. 1 hp f-ly, 1 ill.

Description

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The invention relates to the radiation monitoring of objects using analog-computed tomography methods.

The purpose of the invention is to increase accuracy and sensitivity.

The drawing shows the scheme of the proposed tomograph.

It contains an X-ray or gamma-ray source 1 that forms a flat fan beam 2, a holder 3 of an object under study 4 with a 5 rotation drive, a carrier of a latent image in the video of a radiophotoluminescent glass (RFLS) drive 7 of its linear movement the direction perpendicular to the plane of the radiation beam 2, a means of developing a carrier in the form of an ultraviolet (UV) radiation source 8, an image reading and digitizing device including a photodetector 9 with a drive 10 moving it and in the direction parallel to the plane of the radiation beam 2, and connected to the output of the photoreceiver 9 analog-to-digital converter (ADC) 11, processing unit 12 (computer), display unit 13, drive control unit 14, 5, 7, and 10 and recovery means carrier b in the form of a heater 15.

The proposed tomography works as follows.

At the beginning of the tomographic study, the carrier 6 of RFLS is located with the upper edge slightly above the plane of the beam 2 of the radiation produced by source 1. The drive 5 rotates the holder 3 of the object under study 4 and the drive 7 linearly moves the carrier 6 in step mode synchronously with each other according to commands from block 14 management The source 1 is switched on for a specified time. The flat beam 2 passes through the layer under study, the object 4 under test, and falls onto the carrier 6. in which a latent projection image is formed. Then the source 1 is turned off, the actuator 5 rotates the holder 3 by a given angle, for example 1 °, and the actuator 7 moves the carrier 6 upward by a predetermined distance not less than the thickness of the flat beam of radiation 2. To eliminate the scattered radiation, the plate b can be placed behind the screen with a slit collimator. This procedure is repeated several times until the zone of the first latent projection image reaches the zone of development formed by the source of UV-8, for example, a scanning UV-laser.

When the area of the first latent projection image reaches the area of occurrence, source 8 is turned on, under the action of UV radiation of which the latent image is displayed. The actuator 10 linear movement of the photodetector

9, which reads a projection image. Photodetector 9 signals are digitized in ADC 11 and stored in the memory of processing unit 12. Simultaneously with the appearance and reading of the latent image, the next latent projection image is formed in the manner described. Thereafter, the processes of forming hidden projection images and processes

5 occurrences and readings are performed synchronously. At the end of the angular range of transmission, for example, 180 °, the photodetector reads the remaining projection images. Unit 12 processing known

0, processes the stored digitized signals and restores the tomographic image of the examined layer of the object 4 under examination, to the display unit 13. In addition, by

5, at the end of the readout, the actuator 7 moves the carrier b to the heater 15, which is used for reducing heating of the carrier 6 from RFLS (the recovery temperature of known

0 RFLS is about). After that, the carrier 6 is ready for reuse (each plate of the RFLS permits approximately five times as much as use).

Claims (2)

Claim 1. Analog-computed tomograph containing a source of a fan beam of x-ray or gamma radiation, holder 0 of the object under study, a carrier rotation drive, a latent image carrier, a carrier movement drive, a latent image display means on the carrier, a recovery medium, 5 with the means for developing and restoring one after the other relative to the carrier and offset from the intersection zone of the carrier with the flat ray of the source, 0 a reader and digitizer of the developed image on the carrier, a processing unit, to the inputs of which the reader and digitizer are connected and the coordinate outputs of the drives, and 5, the output is connected to a display unit, and a control unit connected to the corresponding inputs of the source, drives, development means, and reader and digitizing device, characterized in that, in order to improve the accuracy and sensitivity, the carrier is made in it514982016 de plates of radiotoluminescent ka. and the means of manifestation is in the form of a source of glass; the drive for moving the carrier is high ultraviolet radiation; it is filled in the form of a drive for linear motion 2. The tomograph according to claim 1, about tl and h and y and carrier scatter in the direction that the source of ultraviolet radiation perpendicular to the plane of the fan beam is made in the form of ultraviolet radiation. laser.