Which term refers to a detector that is a CMOS with active pixels used to improve image quality?

• A. CMOS-APS
• B. CCD
• C. CMOS
• D. PMT

Answer: (A)

CMOS-APS stands for CMOS active-pixel sensor. This detector design puts amplification and, often, some processing right at each pixel, rather than relying on a separate readout stage after the whole array. That per-pixel amplification improves the signal-to-noise ratio, expands dynamic range, and enables faster, cleaner readout. In dental radiography, this means the image has crisper detail and better contrast, easier to interpret, with less noise especially at low exposures.

A plain CCD relies on transferring charge through the array to a separate readout, which can add noise and slower readout. A PMT is a photomultiplier tube used in older scintillator-based systems and isn’t a solid-state CMOS detector. And simply calling something CMOS doesn’t specify the on-pixel amplification architecture. Because the question describes a detector that is a CMOS with active pixels used to improve image quality, the term that fits exactly is CMOS-APS.