A basic infrared temperature sensor, also known as an infrared thermometer or pyrometer, measures the temperature of an object by detecting the infrared radiation emitted by the object. All objects with a temperature above absolute zero (-273.15°C or 0 Kelvin) emit infrared radiation in the form of electromagnetic waves. The amount of radiation emitted is proportional to the object's temperature.
Here's a basic explanation of how an infrared temperature sensor works:
Infrared Detection: The sensor contains an infrared detector, which is usually a thermopile, a pyroelectric sensor, or a microbolometer. These detectors are sensitive to infrared radiation and can convert the infrared energy into an electrical signal.
Optics: The sensor has an optical system that focuses the infrared radiation from the object onto the detector. This optical system typically consists of a lens or a mirror to capture the infrared rays and direct them onto the detector element.
Signal Processing: The electrical signal generated by the infrared detector is then processed by the sensor's electronics. The signal is amplified and converted into a temperature reading using algorithms that take into account the sensitivity of the detector and the characteristics of the optical system.
Emissivity Compensation: To accurately measure the temperature of an object, the sensor must consider the object's emissivity, which is the ability of a surface to emit thermal radiation. Emissivity varies depending on the material and surface properties of the object. Most infrared thermometers allow users to adjust the emissivity setting based on the material being measured.
Display or Output: The final temperature reading is displayed on a digital screen in the case of handheld infrared thermometers, or it can be output to other devices for further processing and recording.
It's important to note that infrared temperature sensors are non-contact devices, which means they can measure the temperature of objects without physically touching them. This makes them useful for measuring the temperature of moving or hard-to-reach objects, as well as for applications where contact could contaminate the object or affect the measurement accuracy.