CCD sensor
CCDs, Charged-coupled devices, are sensors based on an array of passive photodiodes which integrates charge during the exposure time of the camera.
The charge is then transferred to electronics which reads the accumulated charges of the different pixels and translates them in voltages.
CCD is a passive-pixel device (i.e. with no electronics at pixel level), so the quantum efficiency is very high: this is an advantage in applications where the light is quite poor.
Then, since the electronics is the same for all the pixels, it’s possible to achieve a high pixel uniformity. On the other hand, the charge transfer is quite slow, resulting in a low frame rate (typically <20fps) and they are quite expensive since construction technology is not standard.