What is CCD?

CCD is a charge coupled device.

CCD charge-coupled device, a detection element that uses the amount of charge to represent the signal size and transmits the signal in a coupling manner, has the characteristics of self-scanning, wide spectrum range, small distortion, small size, light weight, and low system noise. It has a series of advantages such as low power consumption, long life, and high reliability, and can be made into a very highly integrated assembly.

CCD is widely used in digital photography, astronomy, especially optical telemetry technology, optical and spectral telescopes and high-speed photography technology, such as Lucky imaging. CCD is widely used in cameras, digital cameras and scanners, but cameras use dot matrix CCD, which includes x and y directions for capturing plane images, while scanners use linear CCD, which only Scanning in the x direction and y direction is completed by the mechanical device of the scanner.

Extended information:

CCD functional characteristics:

CCD image sensor can directly convert optical signals into analog current signals. The current signals are amplified and analog-to-digital converted. , to achieve image acquisition, storage, transmission, processing and reproduction. Its salient features are:

1. Small size and light weight;

2. Low power consumption, low operating voltage, impact and vibration resistance, stable performance and long life;

3. High sensitivity, low noise, and large dynamic range;

4. Fast response, self-scanning function, small image distortion, and no afterimage;

5. It is produced using very large-scale integrated circuit technology, with high pixel integration, precise dimensions, and low commercial production costs. Therefore, many instruments that use optical methods to measure outer diameter use CCD devices as photoelectric receivers.

CCD can be divided into two categories: linear array CCD and area array CCD. Linear array CCD usually divides the internal electrodes of the CCD into arrays, each group is called a phase, and applies the same clock pulse. The required number of phases is determined by the internal structure of the CCD chip. CCDs with different structures can meet the requirements of different occasions.

Linear array CCDs are divided into single-channel and dual-channel. The photosensitive area is a MOS capacitor or photodiode structure, and the production process is relatively simple. It consists of a photosensitive area array and a shift register scanning circuit. It is characterized by fast information processing speed, simple peripheral circuits, and easy real-time control. However, it obtains a small amount of information and cannot process complex images (line array CCD is shown on the right) .

The structure of the area array CCD is much more complex. It consists of many photosensitive areas arranged in a square matrix and connected in a certain form to form a device. It can acquire a large amount of information and can process complex images.

Reference: Baidu Encyclopedia—CDD