Knowledge interpretation of underwater camera TV system

According to the working principle, the underwater camera TV system is divided into visible light underwater camera TV and ultrasonic underwater camera TV.

Visible light underwater camera TV is widely used and consists of a TV camera, transmission cable, controller, and monitor. TV cameras are pressure-resistant, waterproof, and corrosion-resistant. They are carried by divers or installed in submersibles or towed bodies. They usually use high-sensitivity optoelectronic devices with a light sensitivity of 10-4 lux (target surface illumination). The controller and monitor are usually installed on the carrier platform (such as a lifeboat) and are connected to a TV camera through a transmission cable to perform remote control photography and monitor the captured images. According to the needs of users, the visible light underwater camera TV is also equipped with other auxiliary equipment, such as video recorders, underwater lighting fixtures, underwater communication tools, stabilization and rotation devices for fixed cameras, etc. Seawater has a strong absorption and scattering effect on visible light, the energy decays rapidly, and the visible distance is limited. When the water depth is greater than 30 meters, artificial lighting is generally required. In the water with high transparency, the visible distance is about 30 meters. The developing underwater laser TV has a viewing distance farther than the general visible light.

Ultrasonic underwater camera TV uses an ultrasonic transducer array to continuously emit ultrasonic waves to "irradiate" the observed object, the reflected echoes are received by the ultrasonic camera and focused on the image converter by the acoustic lens to become image signals, which are transmitted to the control unit through cables. a device, and then the visual image is displayed on the display. The strength of the image signal depends on the reflection strength and frequency of the ultrasonic waves by the object, and its action distance is farther than that of the visible light underwater camera TV, but it has not been widely used.