Infrared night vision devices can sense infrared rays.
Infrared rays are electromagnetic waves with different properties from visible light, including thermal effects. Infrared rays can be reflected, absorbed, and scattered by objects, so they can be detected by night vision devices and other equipment. Infrared night vision devices detect and receive infrared rays emitted by objects and convert them into visible light images, so that objects in night or dark environments can also be seen.
The working principle of infrared night vision devices is to use the infrared rays emitted by objects to be diffusely reflected, received by the lens of infrared night vision devices, and then undergo photoelectric conversion and signal processing to finally present a clear image. Compared with visible light, infrared rays have the following characteristics:
1. Longer wavelength: The wavelength of infrared rays is longer than that of visible light, so infrared night vision devices can see farther or darker targets.
2. Thermal effect: When an object emits or reflects infrared rays, the intensity and range of the infrared rays will change due to the presence of heat. Infrared night vision devices sense the presence of targets by detecting and receiving these changing infrared rays.
3. Not easy to be scattered: Compared with visible light, infrared rays are not easy to be scattered, so they can penetrate thinner materials such as fog, rain, and snow.
4. Susceptible to interference: Infrared rays propagate slower in the air than visible light, so they are easily scattered or absorbed by materials such as leaves, smoke, and dust, which affects the performance of infrared night vision devices.
Although infrared rays have some limitations, infrared night vision devices are still very useful tools in some specific situations. For example, in military and police operations, observation and search are required at night or in bad weather, and infrared night vision devices can provide better observation and aiming capabilities.
In addition, in scientific research and medical fields, there are also some special equipment that use infrared rays for observation and diagnosis. In short, infrared night vision devices can sense infrared rays.
