How do infrared temperature sensors work

On the contrary, an infrared thermometer with a narrow temperature range is better where higher resolutions are necessary to ensure proper temperature control of a specific process. Reading speed is a time the thermometer takes to deliver an accurate reading after initiating the thermometer's reading process.

This factor is essential when measuring the temperature of a moving object, or in cases where the objects heat up quickly. Industrial IR thermometers must have a rugged design. No-lens and Fresnel lens thermometers are durable due to their polymer structure, which keeps them safe. Whereas, tough Mica lens thermometers need a more durable shell and a carrying case implemented into their design to prevent the lens from cracking.

Warranty is a must-have feature in thermometers, as they are fragile or may even turn out to be defective. No-lens and Fresnel thermometers are cheaper than Mica lens thermometers, which can be a pretty massive investment. If you are buying any expensive thermometer, get the one that comes with a manufacturer's warranty.

Infrared thermometers are essential to use while reading the temperature of a surface that's too dangerous, and almost impossible to reach. With the complex inner workings process, these thermometers give rapid results and are simple to use. However, before picking an IR thermometer, try to figure out the temperature range and your application. Also, make sure to use the device correctly and at the right place to get accurate results.

Radiation is a process where heat energy in a form of electromagnetic waves is emitted by a hot object and absorbed by a colder object. Most of this radiation is in the infrared IR region of the electromagnetic spectrum, but some also spread into the visible light band. The IR wavelength band stretches from 0.

If an object is exposed to IR energy radiated by a heat source, such as an electric heater, light bulb, sun, or other sources, the energy reaching the object is called incident energy. Part of this energy is reflected off the object surface. Rough, matt surfaces have low reflectivity. Polished and glossy surfaces, especially metals, have high reflectivity. Depending on the object material, thickness, and the radiation wavelength, part of the radiation can go through the object or be transmitted.

The coefficient of transmission can vary from 0 no energy transmitted through object to 1. High transmittance examples include glass, quartz, plastic film, and various gasses. Materials opaque in the IR spectrum have close to zero transmission coefficients. The remaining energy is absorbed by the object and raises its temperature. A hypothetical body that has no reflection or transmission and absorbs all incident energy across the entire spectrum has a coefficient of absorption equal to 1.

Real-life objects, referred to as gray bodies, have coefficients of absorption that fall between 0 and 1. As the object absorbs energy and heats, it also emits energy. When an object absorbs more energy and its temperature increases, the amount of radiation it emits also increases. IR thermometry is based on the fact that anybody solid, liquid, or gaseous that has a temperature above absolute zero 0 o K or o C emits radiant energy.

Energy radiated by a body can be expressed as follows:. Emissivity can range from 0 to 1 for various bodies. A hypothetical blackbody emits and absorbs all energy and thus has an emissivity equal to 1.

Real-life objects have an emissivity between 0 and 1. That is, in addition to emitting energy related to its own temperature, the object may reflect energy coming from another source, or transmit energy passing through it from a source behind it.

For accurate measurements, survey the surrounding area for possible sources of extraneous IR radiation and choose the thermometer position and aiming angle to minimize the effects of those sources. IR Thermometers Infrared temperature sensor instrument design varies from simple hand-held thermometers that can be purchased for less than a hundred dollars to complex special-purpose instruments that cost hundreds and even thousands of dollars.

However, some building blocks are common for most designs. If you are going to be back a significant distance, make sure the model you pick out is capable of remaining accurate thanks to a large distance-to-spot ratio. Although infrared thermometers are limited to taking surface temperature readings, they remain a valuable tool that is used by professionals in a variety of industries. When you are picking out your own IR unit, be sure to pay close attention to both the distance-to-spot ratio, as well as the temperature range that is offered by that model.

Once you do receive your thermometer, read all of the instructions carefully and use the unit in accordance to the manufacturer's recommendations in order to get the most accurate readings possible. While not the perfect tool for every temperature measuring job, there is a good chance you will find plenty of occasions to put an IR thermometer to work for you.

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The store will not work correctly in the case when cookies are disabled. How Do Infrared Thermometers Work? A Simple Principle While the technology that makes these thermometers work is certainly complex, the concept itself is rather simple. Why Infrared? Getting in Range It is important to pick an infrared thermometer that is rated to measure items within the temperature range that will be applicable to your uses. Distance-to-Spot Ratio Another important element of IR thermometers is the distance-to-spot ratio that they offer.

Posted in: How To's. Leave a Reply Name. If an object is very fragile or dangerous to be near, for example, an infrared thermometer is a good way to get a temperature from a safe distance. Infrared thermometers work based on a phenomenon called black body radiation.

Anything at a temperature above absolute zero has molecules inside of it moving around. The higher the temperature, the faster the molecules move. As they move, the molecules emit infrared radiation--a type of electromagnetic radiation below the visible spectrum of light. As they get hotter, they emit more infrared, and even start to emit visible light. That is why heated metal can glow red or even white. Infrared thermometers detect and measure this radiation.

Infrared light works like visible light--it can be focused, reflected or absorbed. Infrared thermometers usually use a lens to focus infrared light from one object onto a detector called a thermopile. The thermopile absorbs the infrared radiation and turns it into heat.