Which is better: CCD or CMOS? Criterias of choice

The matrix is the basis of any photo or video device. It determines the quality and size of the resulting image. To date, the manufacture of matrices uses two different technological principles - CCD and CMOS. Very often you can hear the question: "What kind of matrix should I choose: CCD or CMOS?" Among the fans of photo and video equipment there are heated debates about this. In this article we will review these two types and try to figure out which matrix is better - CCD or CMOS.

general information

The matrices are designed to digitize the parameters of light rays on their surface. It is not possible to talk about the obvious advantage of one of the technologies. You can compare by specific parameters and identify the leader in one or another aspect. As for the preferences of users, often for them the main criterion is the cost of the product, even if it is inferior in quality or technical characteristics to its competitor.

So, let's look at what both types of devices are. CCD-matrix - a chip that consists of photosensitive photodiodes; It is built on a silicon base. The peculiarity of her work lies in the principle of the action of the device with a charge bond. CMOS-matrix is a device created on the basis of semiconductor field-effect transistors having an isolated gate with channels of various conductivity.

Principle of operation

Let's go on to identify the differences that will help determine the choice: what is better - the matrix CMOS or CCD? The main difference between these two technologies is the principle of their operation. CCD-devices charge from pixels are converted into electrical potential, which is amplified outside the photosensitive sensors. The result is an analog image. After that, the entire image is digitized in the ADC. That is, the device consists of two parts - directly the matrix and the converter. CMOS technology is characterized by the fact that it digitizes each pixel separately. At the output, you get a ready-made digital picture. That is, the electric charge in the matrix pixel is accumulated in the capacitor, from which the electric potential is removed. It is transmitted to an analog amplifier (built-in directly in the pixel), and then digitized in the converter.

What to choose: CCD or CMOS?

One of the important parameters that determine the choice between these technologies is the number of matrix amplifiers. CMOS-devices have a greater number of these devices (at each point), therefore, when the signal passes, the quality of the picture is somewhat reduced. Therefore, CCD-matrices are used to create images with a high degree of detail, for example, for medical, research, industrial purposes. But CMOS-technology is used mainly in household appliances: web cameras, smartphones, tablets, laptops, etc.

The next parameter that determines which type is better is CCD or CMOS, is the density of the photodiodes. The higher it is, the fewer photons "it will go to waste," respectively, the image will be better. In this parameter, CCD matrices bypass their competitors, as they offer a layout that does not have such gaps, whereas CMOS has them (transistors are located in them).

However, when the user gets a choice: what type of matrix - CMOS or CCD - to buy, the main parameter - the price of the device - pops up. CCD-technology is much more expensive than its competitor and more energy-efficient. Therefore, it is not advisable to install them wherever medium-quality images are sufficient.