A camera is a machine that converts optical image signals into electrical signals for storage or transmission. When we shoot an object, the light reflected on the object is collected by the camera lens, so that it is focused on the light-receiving surface of the camera device (such as the target surface of the camera tube), and then the light is converted into electrical energy by the camera device, which is obtained "Video Signal". The photoelectric signal is very weak and needs to be amplified by a pre-amplifier circuit, and then processed and adjusted by various circuits. The final standard signal can be sent to a video recorder and other recording media for recording, or transmitted through a propagation system or sent to a monitor show.
The camera uses visible light for imaging. When the light molecules of various visible light reach the CCD (photosensitive device) of the camera, the image is presented through electronic technology. When the light intensity is better, the camera's imaging is also better, but as the illuminance (intensity) of the light decreases, the imaging also becomes worse. The main manifestation is that the appearance of "noise" increases and the image also increases. It becomes blurred (such as the change of camera image at dusk). As the illuminance of the light weakens further, the color camera can no longer image.
