What is a Pyrometer? Understanding the Basics of Non-Contact Temperature Sensors
What is a pyrometer? A pyrometer is an optical instrument that remotely converts the energy emitted by a hot target into a numerical value, known as the target temperature. Each hot target emits infrared radiation, which, within a specific solid angle created by the pyrometer’s optical system, is filtered through a spectral filter before reaching the photodetector. The photodetector converts this radiation into an electrical signal (see pyrometer layout below). The controller receives this electrical signal and uses a calibration graph stored in memory to convert it into a temperature reading.
The measurement spot size depends on the relationship between the working distance and the focal length of the objective, as well as the diameter of the photodetector diaphragm.
The spectral range of the pyrometer is defined by the spectral transition of the filter, which the photodetector must cover.
The aperture diaphragm manages the temperature range tuning, and the pyrometer can be aimed at a hot target using either a visual telescope or a laser.