Which two technologies are commonly used in solid-state detectors?

• A. CCD and CMOS
• B. PSP and CCD
• C. Scintillator and Photodiode
• D. Photomultiplier and APD

Answer: (A)

Solid-state detectors rely on semiconductor devices that directly convert radiation or the light it produces into an electrical signal within a silicon substrate. The two technologies most commonly used for imaging detectors are CCDs and CMOS sensors. Both are solid-state image sensors built as pixel arrays on silicon, which lets them capture and read out signals in a compact, integrated form. CCDs traditionally transfer charge across the array to a readout node, providing high uniformity and low noise in many setups, while CMOS sensors put more of the readout electronics in each pixel, enabling lower power, faster readout, and easier integration with other circuitry. This combination of direct, solid-state signal conversion in a pixelated silicon array is what makes CCD and CMOS the standard choices for solid-state detectors. Other options involve different detection concepts—PSP plates are storage phosphor plates used in computed radiography, not solid-state detectors; photomultiplier tubes are vacuum-tube devices; a scintillator paired with a photodiode is a light-conversion approach but not a pure solid-state imaging sensor like CCD or CMOS.