What Is an Infrared Camera?
An infrared camera is a camera that creates images by capturing “infrared light,” a type of electromagnetic radiation.
Normal digital cameras take pictures using electromagnetic waves called “visible light,” which is visible to the human eye. These cameras have the problem that it is difficult to take pictures in the dark, or other environments where there is no light source.
Infrared cameras use infrared light, not visible light, to take pictures. Infrared radiation is emitted from all objects except those that don’t have heat, i.e., those that are at absolute zero. Therefore, an infrared camera that can detect infrared light can take pictures with or without a light source, unlike a normal camera.
Uses of Infrared Cameras
Infrared cameras are unique in that they can detect infrared radiation that cannot be captured by ordinary digital cameras. They are used as security cameras and surveillance cameras because they can be used in dark places where it is difficult for normal digital cameras to capture images.
The infrared radiation emitted by an object can also provide information on the object’s heat and temperature, as well as information on the object’s composition. Therefore, infrared cameras are widely used for applications other than simple cameras, such as temperature control and inspections of production processes and infrastructure.
Principle of Infrared Cameras
Infrared cameras are special cameras that use infrared light to take pictures, but the configuration and principle of operation itself is basically the same as that of a regular digital camera.
Infrared cameras have an infrared sensor built into the camera, which acts as the “image sensor” in a normal digital camera. The infrared sensor consists of a regular array of tiny elements called pixels.
Each material used in an infrared sensor has a different range of detectable infrared light. For example, indium antimonide sensors have a range of 1.5 to 5.1 µm. It is therefore important to check that the infrared radiation emitted by the object being photographed is included in the detection range before use.
Like ordinary digital cameras, infrared cameras are also equipped with a lens that directs the captured light to the sensor. Various types of lenses are available for normal and close-up photography, and the most appropriate one should be selected according to the size of the object to be photographed and other factors.