An infrared camera or thermal imaging camera is a device for non-contact temperature measurement of a measurement object. Its design is similar to that of a conventional camera. However, the infrared camera does not operate by analyzing visible light; rather, it analyzes infrared radiation.
Similar to a pyrometer, the infrared radiation emitted by the measurement object is focused on an infrared detector. Focal plane arrays, which consist of thin-film bolometers that are arranged in a matrix, are often used as detectors here. This makes it possible to two-dimensionally evaluate the infrared radiation emitted by a measurement object.
Infrared cameras furthermore differ from conventional cameras due to the cooled and uncooled infrared detector. Cooled infrared cameras use cryogenic cooling in order to keep the infrared detector at a consistent, low temperature.
Compared to visual cameras, infrared cameras have a significantly lower resolution. Typical resolutions for industrial infrared cameras are 160x120, 320x240 and 640x480 pixels. As a result, infrared cameras are suitable for depicting temperature distributions or temperature changes over larger areas. In order to determine the object’s temperature, the emissivity must be known. The possible size of the measurement field is determined by the field of view. Images from an infrared camera are visualized in a false-color display, wherein various colors represent different temperatures.