Today we will have a look on second most important part in CT - detector.
In industrial CT is used plane detector, but exceptions can be found in R&D where is used line detector.
Detectors resolution can be from 1000x1000px to 4000x4000px. Higher resolutions are pointless these days because of tiny pixels and small gain - that results in big image noise. Best compromise is 4Mpx (2000x2000px).
Every pixel is nearly the same as these in CCD chips - most CT X-ray detectors utilize scintillators. Important parameters are scintillator material, size and geometry, and the means by which scintillation events are detected and counted. Common scintillation materials are cesium iodide, gadolinium oxysulfide, and sodium metatungstate.
Scintilator principe
Thats all what is needed to know about detectors, next time we will talk about design and principes.
Parts:
Part 1 - Tube