What does ccd mean?

CCD charge-coupled device, a detection element that uses the amount of charge to express 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 used in: digital photography and astronomy.

Extended information:

General color digital cameras have a Bayer filter installed on the CCD. Every four pixels form a unit, one is responsible for filtering red, one is filtering blue, and two are filtering green (because the human eye is more sensitive to green). As a result, each pixel receives a photosensitive signal, but the color resolution is not as good as the photosensitive resolution.

The 3CCD system composed of three CCDs and a dichroic prism can separate colors better. The dichroic prism can analyze the incident light into three colors of red, blue and green light, and each of the three CCDs is responsible for it. The appearance of a color of light. All professional-grade digital cameras, and some semi-professional-grade digital cameras use 3CCD technology.

As of 2005, ultra-high-resolution CCD chips are still quite expensive, and the price of still cameras equipped with 3CCD is often beyond the budget of many professional photographers. Therefore some high-end cameras use rotating color filters. This type of multi-imaging camera can only be used to photograph static objects.

CCD is made of a high-sensitivity semiconductor material, which can convert light into electric charges and convert them into digital signals through an analog-to-digital converter chip. The digital signals are compressed by the flash inside the camera. Memory or built-in hard disk card storage, so the data can be easily transferred to the computer, and with the help of computer processing means, the image can be modified according to needs and imagination. A CCD is composed of many photosensitive units, usually measured in megapixels. When the CCD surface is illuminated by light, each photosensitive unit will reflect the charge on the component, and the signals generated by all the photosensitive units are added together to form a complete picture.

CCD is an extremely important component in a camera. It converts light into electrical signals, similar to the human eye, so its performance will directly affect the performance of the camera.

There are many indicators to measure the quality of CCD, including the number of pixels, CCD size, sensitivity, signal-to-noise ratio, etc. Among them, the number of pixels and CCD size are important indicators. The number of pixels refers to the number of photosensitive elements on the CCD. The picture captured by the camera can be understood as consisting of many small points, each point is a pixel.

Obviously, the more pixels, the clearer the picture will be. If the CCD does not have enough pixels, the clarity of the captured picture will be greatly affected. Therefore, in theory, the number of pixels of the CCD should The more, the better. However, the increase in the number of CCD pixels will reduce the manufacturing cost and yield. Moreover, under the current TV standards, after the number of pixels increases to a certain number, the effect of increasing the number of pixels on improving the clarity of the captured images becomes insignificant. Therefore, generally A pixel count of around a million is sufficient for general use.

Single CCD camera means that there is only one CCD in the camera and it is used for photoelectric conversion of brightness signal and color signal. The chrominance signal uses some specific color mask devices on the CCD and is combined with the following circuits. Completed. Since a CCD completes the conversion of brightness signals and chrominance signals at the same time, it is inevitable to have both, making the captured images unable to meet professional level requirements in terms of color reproduction.

In order to solve this problem, 3CCD cameras appeared. 3CCD, as the name suggests, is a camera using 3 CCDs. We know that if light passes through a special prism, it will be divided into three colors: red, green, and blue. These three colors are the three primary colors used by our TVs. Through these three primary colors, brightness signals can be generated. All TV signals included. If a CCD is used to receive each color and convert it into an electrical signal, and then processed by a circuit to generate an image signal, a 3CCD system is formed.

Compared with a single CCD, because 3CCD uses three CCDs to convert red, green, and blue signals respectively, the color reproduction of the captured images is more natural than that of a single CCD, and the brightness and clarity are also higher. Single CCD is better. However, due to the use of three CCDs, the price of a 3CCD camera is much more expensive than a single CCD.

Four-color CCD is a new CCD technology launched by Sony in 2003. Compared with the traditional three colors (red, green, blue), the color reproduction error rate of the four-color CCD is further reduced. This makes color reproduction more realistic. The first digital camera using a four-color CCD was the SONY DSC-F828.

The CCD column in digital camera specification sheets often says "1/2.7-inch CCD" and so on. The "1/2.7 inch" here is the size of the CCD, which is actually the diagonal length of the CCD.

Reference: Baidu Encyclopedia-CCD