nonCCD

nonCCD is a term used in imaging science and astronomy to refer to any detector technology that does not employ a charge‐coupled device (CCD) for photon detection and conversion into an electrical signal. The most common nonCCD devices include complement​ary metal‑oxide‑semiconductor (CMOS) sensors, photomultiplier tubes (PMTs), avalanche photodiodes (APDs), silicon photomultipliers (SiPMs), and other solid‑state or vacuum‑tube based sensors.

CMOS sensors, the workhorse of consumer digital cameras and many scientific instruments, differ from CCDs in that each pixel has its own readout circuitry, allowing for faster readout speeds, lower power consumption, and on‑chip processing. However, traditional CMOS technology historically suffered from higher read noise and lower quantum efficiency compared to CCDs, though recent advances have largely closed that gap.

PMTs and APDs are vacuum‑tube or semiconductor devices that amplify the signal at the point of photon conversion, providing extremely high sensitivity and temporal resolution. SiPMs combine the benefits of solid‑state technology with PMT‑like gain, making them attractive for applications such as particle physics detectors, LIDAR, and medical imaging (PET scanners).

While CCDs remain favored in many high‑precision astronomical surveys due to their low noise and uniform response across the array, nonCCD technologies are rapidly expanding the range of available imaging solutions. Their strengths include faster readout, lower voltage operation, and compatibility with integrated electronics, while their downsides can include higher dark current, increased cost, or more complex calibration. The choice between CCD and nonCCD sensors is therefore dictated by the specific requirements of the imaging application, such as sensitivity, speed, resolution, and environmental constraints.