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What is a Digital Infrared Thermometer?

Patrick Roland
Patrick Roland

When surface temperatures need to be measured but are too hot or too difficult to read with traditional methods, a digital infrared thermometer is a popular solution. This laser guided, gun-like tool uses infrared technology to provide thermal readings quickly and accurately. It is simple to operate and performs an incredibly complex procedure inside a small casing.

A digital infrared thermometer has a pistol shape and usually is constructed of hard plastic with one or two lenses, similar to a small flashlight. Digital thermometers also have a small light-emitting diode (LED) reading area that displays the temperature. One of the most unique aspects of this tool is its guide that produces a small red laser point to help the user aim the thermometer with precision. Like firing a pistol, users pull a trigger and hold the red laser dot over the surface for a few seconds in order to get a reading.

Woman holding a disc
Woman holding a disc

The process of attaining an accurate temperature reading is impressively simple, but the science behind getting the reading is surprisingly complex for the digital infrared thermometer. Infrared thermometers pull in a temperature by allowing infrared radiation to pass through the lens. There, a rotating disc known as an optical chopper slices the radiation beam into dozens of snippets per second. Simultaneously, a filament within the gun shoots radiation beams toward the object being measured. The internal computer on the thermometer calculates the difference between the incoming and outgoing heat measurements and provides an accurate reading.

A digital infrared thermometer is an ideal way to get a Fahrenheit or Celsius reading on many different objects. In cooking, a laser thermometer is useful in measuring the surface heat of items such as charcoal grills or gas burners. Chefs also use these to check the temperature of liquids, such as soups, to ensure that they are at an appropriate serving temperature. Other industries, such as laboratory work, use digital infrared thermometers to measure temperatures in chemical mixtures where the surface is too hot or too dangerous.

A digital infrared thermometer is useful in many areas but is not a good match for all temperature-taking needs. When measuring shiny surfaces, such as chrome, the gun cannot get an accurate reading because of the reflection. Additionally, kitchens must use traditional probe thermometers to get internal meat readings because lasers can provide only surface temperatures.

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    • Woman holding a disc
      Woman holding a disc