A basic infrared temperature sensor, also known as an infrared thermometer or non-contact thermometer, measures the temperature of an object by detecting and analyzing the infrared radiation emitted by the object. All objects with a temperature above absolute zero emit infrared radiation, which is a form of electromagnetic radiation.
Here's how a basic infrared temperature sensor works:
Infrared Sensor: The sensor typically contains a detector that is sensitive to infrared radiation. The most common type of detector used in basic infrared thermometers is a thermopile. A thermopile consists of multiple thermocouples connected in series, which generates a small voltage proportional to the temperature difference between the sensor and the object being measured.
Optics: The sensor is equipped with an optical system that helps to focus the infrared radiation emitted by the object onto the thermopile. This system usually consists of lenses and sometimes a mirror.
Emissivity Compensation: Different materials emit infrared radiation differently, and the sensor needs to compensate for the object's emissivity to provide accurate temperature readings. Emissivity is a measure of how well an object radiates infrared energy compared to a perfect blackbody radiator (which has an emissivity of 1). The sensor may have an adjustable emissivity setting or a default value to account for different object types.
Measurement: When you point the infrared temperature sensor at an object, the optics focus the infrared radiation from the object onto the thermopile. The thermopile generates a voltage proportional to the amount of infrared radiation detected. This voltage is then converted into a temperature reading through calibration and signal processing algorithms.
Display: The temperature reading is displayed on a screen, usually in degrees Celsius (°C) or Fahrenheit (°F), allowing you to see the object's temperature without making physical contact.
It's important to note that infrared thermometers measure the surface temperature of the object and not the internal temperature. Additionally, the accuracy and range of a basic infrared temperature sensor can vary based on its design and quality. For precise and critical applications, more sophisticated infrared temperature sensors with higher accuracy and additional features are available.