Industrial camera is an indispensable part of modern industrial automated production. As an important machine vision component, it can quickly and accurately acquire various information in the production process, such as position, size, colour, etc., through image acquisition and data processing. It is widely used in product quality inspection, production process control, automated assembly line operation, etc., which greatly improves production efficiency and product quality.

Gain adjustment is one of the important functions of the industrial camera, refers to the camera acquired image signal amplification or reduction, it can help the industrial camera to adapt to different application scenarios and needs, improve image quality, detection accuracy and speed, reduce noise interference, so as to better meet the needs of industrial automation production.

The principle of image acquisition gain of industrial cameras mainly involves analogue gain and digital gain in two aspects.

Analogue gain: analogue gain is achieved by adjusting the electronic amplification of the camera. Before the camera acquires the image signal, the image signal is amplified through the analogue circuit. The size of the analogue gain depends on the electronic amplification and the sensor type. When lighting conditions are poor or the contrast of the target object is low, increasing the analogue gain increases the intensity of the image signal, thereby improving the brightness and contrast of the image. However, increasing analogue gain also increases the noise level of the image, so there is a trade-off between image brightness and noise level.

Digital Gain: Digital gain is achieved by increasing the pixel value after the camera has acquired the image signal. The raw image signal captured by the camera is converted to analogue-to-digital to obtain digitised pixel values, and digital gain is a linear amplification of these pixel values. Digital gain does not introduce additional noise, so it can effectively increase the brightness and contrast of an image. Digital gain can be achieved through software or hardware, where hardware implementation usually uses DSP (Digital Signal Processor) or FPGA (Field Programmable Gate Array) and other technologies.

In short, the principle of industrial camera acquisition gain is achieved by adjusting the analogue gain and digital gain of the camera. In practical applications, according to different lighting conditions and image quality requirements to reasonably adjust the size of the camera gain. At the same time, it is also necessary to combine other parameters and indicators, such as resolution, exposure time, sensor type, etc., in order to achieve the best image acquisition results.