Working principle of CCD and CMOS sensors

CCD is the abbreviation of Charge CoupLED Device in English, Chinese translates as the charge coupled device. It was developed in 1969 by W.B. Boyle and G.E. Smith of Bell Laboratories in the United States. It uses a high-sensitivity It is made of semiconductor material and contains many photosensitive elements. Each photosensitive element is called a pixel. CCD can be regarded as an assembly of these pixels. When the surface of the CCD is exposed to light, each photosensitive unit reflects the charge on the component, and the signals generated by all the photosensitive units are added together to form a complete picture.

The full name of CMOS in English is Comple? -Mentary Metal-Oxide Semicon? -Ductor, which is a complementary metal oxide semiconductor, and like CCD, it is also a semiconductor that records light changes. The manufacturing technology of CMOS is no different from that of general computer chips. It is mainly a semiconductor made of silicon and germanium, which coexist with negatively charged (N pole) and positively charged (P pole) semiconductors on CMOS. The current generated by the two complementary effects can be recorded and interpreted as an image by the processing chip. Then through the on-chip analog-to-digital converter (ADC) to convert the obtained analog image signal into a digital signal output.

It can be seen that whether it is CCD or CMOS, they all use photosensitive elements as the basic means of image capture. The core is a photodiode. This diode can produce an output current after being exposed to light, and the intensity of the current is Corresponds to the intensity of light.