How does infrared thermometer work?

How does infrared thermometer work?

When you think about a thermometer, you probably picture a device with some kind of probe that is placed into the object being measured. Whether it is a thermometer that you place under your tongue to take your own temperature, or a food thermometer that you push into a piece of meat to make sure it is done, probe-style thermometers have long been a standard. However, there are plenty of other options on the market today, and infrared thermometers are among the most exciting and useful styles to consider. Offering ease of use and accurate readings, there is a lot to like about an infrared option.

An infrared thermometer may be called for anytime the surface temperature of an object needs to be determined. Obviously, since the infrared beam is only bouncing off of the surface, this is not a suitable method of measurement when the interior temperature of an object needs to be found. There are nearly countless applications, and this technology is already used in a wide range of industries. Checking the level of heat coming from a piece of equipment, for instance, is a good way to check for trouble that may be occurring on the inside. If the equipment is hotter than it should be on the surface, there is a good chance that something is going wrong internally. Considering how many various infrared thermometer models are available today, and how accurate they have become, it is easy to see why they are a popular choice in a number of industries.


While the technology that makes these thermometers work is certainly complex, the concept itself is rather simple. Everything that has mass emits some amount of energy, and that energy is emitted in the form of heat. Since there is heat being emitted by any object, an infrared thermometer can use the difference between the IR rays coming off of the object and the surrounding environment to determine the surface temperature of the object itself.

The IR thermometer works by focusing light that is coming from the object in the form of IR rays and funneling that light into a detector – which is also known as a thermopile. It is in the thermopile that the IR radiation is turned into heat which is then turned to electricity, which is then measured. It is ultimately the amount of electricity that is generated by the rays being put out by the object in question that will provide a reading that is displayed on the thermometer. The reading will be generated in a manner of seconds, meaning an infrared thermometer is a quick way to gather a temperature reading in a number of different scenarios.


There are a number of reasons why you should consider choosing infrared technology for your temperature reading needs. When shopping for a thermometer to add to your stable of equipment, consider purchasing a quality infrared thermometer for some of the following reasons.

1. Accuracy. Obviously, you need to be confident that you are getting an accurate reading from your thermometer when you put it to use, and infrared models have a great reputation for accuracy. The technology used in these products is simple yet advanced, and you should be able to rely on the information that you receive – provided that the thermometer is used in the right way.

2. Safety. One of the great things about being able to check on temperature remotely is that you don’t actually need to touch the object in question. If you are trying to take the temperature of a particularly hot item, you won’t need to place your hand, or even another piece of equipment, onto the hot surface. Just by aiming your IR thermometer at the object you wish to measure, you can get all of the information you need without putting yourself at risk.

3. Contamination prevention. Another benefit to the remote measuring system is avoidance of contamination. This is particularly important within the food service world, but it applies in other applications as well. Since you don’t need to touch the item that you are measure, you won’t need to worry about contaminating that product with the probe of a thermometer. Rather than having to make sure that all of your temperature measuring equipment is properly sterilized prior to each use, you can simply point the IR gun at the item being measured and forget any worries about contamination problems.

4. Durability. You want an Infrared Thermometer that is tough enough to stand up to the demands of the jobsite, workshop or just being bounced around in your toolbox.

There are certainly more than three advantages to using infrared, but the three listed above are some of the most important. Additionally, the cost of this technology has come down in recent years, meaning you can access this great method of temperature measurement for a significantly lower cost than it would have required just a few short years ago.


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. Every IR unit on the market today is rated for a specific range of temperatures, and it will not be accurate if you are trying to measure items that fall outside of that range. Therefore, before picking out an infrared thermometer, you are going to need to think carefully about what you will be measuring and the expected temperature ranges for those items.

As an example, you may find one unit that is capable of measuring temperatures from as low as -40F all the way up to 428F while another unit ranges from -4F all the way up to 626F. Most units will be suitable for covering moderate temperatures, but you need to carefully check the specs on any infrared thermometer that is being purchased for the purpose of measuring extremely cold or extremely hot items.

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