Method and apparatus for radiography and radiation detector

Abstract

A method and apparatus for radiography and also a detector for detecting incident radiation. In the method and the apparatus X-rays (9) are emitted from an X-ray source (60). Said X-rays which have interfered with an object to be imaged are detected (62) in a detector (64). The detector (64), which detects incident radiation is a gaseous avalanche chamber, including electrode arrangements between which a voltage is applied for creating an electrical field, which causes electron-ion avalanches of primary and secondary ionisation electrons released by incident radiation. The detector detects electrical signals in at least two detector electrode modules, said electrical signals being induced by electron-ion avalanches, in at least one of a plurality of detector electrode elements arranged adjacent to each other, each along a direction being essentially parallel to the incident radiation, and where the at least two independent detector electrode modules are arranged in close proximity to each other, each along a direction being essentially parallel to the incident radiation.

Description

field of invention [0001] The present invention relates to a method and apparatus for radiography and a gas avalanche detector. Background of the invention [0002] X-rays have been used in radiography for a long time and have been greatly developed. In its simplest form, imaging is performed by providing a source of x-rays, an imaged object penetrated by the radiation, and a detector for detecting and recording the transmitted radiation. X-rays can also be scattered by the imaged object and detected by the detector. X-ray detectors currently used in hospitals are usually composed of screen membranes. In phosphorus screens (such as Gd 2 o 2 In S), X-ray photons are converted, thereby generating secondary light, which is recorded onto the optical imaging film. The use of imaging films limits the dynamic range of imaging. Because secondary light is emitted isotropically, phosphor screens are used to improve efficiency by sacrificing resolution. [0003] Current digital ...

AI Technical Summary

Problems solved by technology

[0006] A disadvantage of the above-mentioned prior art is that each module of the detector must be in physical and electrical contact with another module to produce the large-area X-ray image capture element described, which leads to high production and assembly costs

[0007] Another disadvantage of module detectors of the type described above is that the data and addressing circuits of each module have to be connected to the corresponding circuits of adjacent modules, which will also lead to higher assembly costs

[0008] A further disadvantage of module detectors of the type described above is that a cracked module cannot be replaced, if possible, without removing and redepositing the radiation detecting layer.

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