How to Choose Non-Contact Infrared Thermometer


There are several reasons why you may need to use a non-contact thermometer. Aside from reading a person’s internal temperature, it can also be used to read food temperature. In the industrial sector, it can also be used to find faulty terminations in high-powered electrical circuits or to locate overloaded circuit breakers, as well as identify fuses at their rated capacity.

Before you can use the best non-contact thermometer, you need first to identify the different types of this thermometer.

Types of Infrared Thermal Measuring Instrument

The biggest difference when it comes to the different types of thermometers is their lenses. This is the reason why they are categorized as no-lens, Fresnel lens, and mica lens.

1. No-lens

No-lens thermometers are inexpensive but durable. These are also easy to use and work perfectly particularly for cold environments. Compared to the other types, a no-lens thermometer is smaller in size, but these don’t have long-distance capabilities.

2. Fresnel Lens

The Fresnel lens thermometer is often used in the food industry. Aside from being inexpensive, these often come with a laser guide. Perhaps the drawback of using this thermometer is that you need to adjust it time and again, particularly when you move between different environments with a sudden drop in temperature.

3. Mica Lens

Among the different types of thermometers, the Mica lens proves to be the most expensive one. Perhaps because of its capability to take temperatures even over long distances. This type of thermometer can also read extreme temperatures accurately, which makes them great for industrial use. You just need to be careful in handling this type of thermometer because they can break easily.

Once you have a good idea of the specific type of thermometer that you need, then you will be able to choose the best one that will suit your requirements. Alongside this, it will also help if you consider some of the factors below.

Temperature Range

Different types of thermometers have varying temperature ranges. For instance, a no-lens infrared thermometer often only gives out an accurate reading when it is used under cold temperatures.

In case you need to measure temperature in a hot environment, then you need to use a Fresnel or a Mica lens thermometer. In case you need to measure temperature in an extreme environment, then make sure to go for a Mica lens thermometer.

Accuracy Rating

Even if the thermometer is non-contact, they must yield accurate measurements. Once they fail to achieve the accuracy that you need, several issues may start to arise. In this case, always consider the accuracy rating of the thermometer when you are choosing what to use. For instance, a no-lens thermometer may give out inaccurate results once you use it in a hot environment.


Emissivity is the measure of how much-infrared energy a thermometer can emit. This parameter is measured on a scale of 0 to 1 wherein if the thermometer has an emissivity of 1, then it means that it can read the temperature of most organic materials accurately.

However, this also means that it will not be able to read the temperature of metal or synthetic materials accurately. As much as possible, go for a thermometer with an adjustable emissivity for you to be able to tweak the amount of infrared energy that you need to put out to read the temperature of different materials.

Read Speed

The read speed of a thermometer is the amount of time it takes for the device to deliver an accurate temperature reading. As much as possible, you would want to acquire one with the capability to read temperatures in a matter of seconds. This will support your efficiency in any process.

However, thermometers with a faster read speed tend to be more expensive, too, such that you need to balance between the cost of the device and its read speed capability.

Design and Backlit Display

Ideally, you would want a thermometer that is made from durable materials such as no-lens or Fresnel lens type thermometers. In this case, you no longer need to get a carrying case to ensure that they are not easily damaged. Mica lens, on the other hand, can easily break, such that you need a more durable shell to ensure that it will not break when you use it.

Aside from the durability of the device, you may want to check other features as well, such as a recording capability that is beneficial if you are reading the temperature of the same object frequently. This is often tied up to a software that will show you the average temperature of the object over a certain period.

In addition to this, a backlit display will prove to be beneficial particularly if you often work in an environment that is poorly lit. Otherwise, a backlit display may not be necessary. But then again, it boils down to balancing your need when it comes to the environment that you need to work in, the accuracy level of the reading that you need, as well as the durability of the device.


Finally, go for thermometer brands that offer a warranty because even if your thermometer eventually breaks, it will be frustrating if it does within days or weeks after you purchase it. If you go for a no-lens or Fresnel lens type of thermometer, having a warranty may not be a priority particularly because these types of thermometers are quite inexpensive.

However, when it comes to a Mica lens thermometer, make sure that the device has a warranty to ensure that you will get your money’s value.

In conclusion, there are several types of thermometer that you can choose from, which uses infrared technology. Once you know the specific type that you need, you will already be able to consider its temperature range, accuracy rating, emissivity, read speed, as well as its design and backlit display.

Of course, you also need to consider its warranty because this protects your right as a consumer should you encounter any issues with the device that you have purchased.

Read More Articles

Leave a comment

Please note, comments must be approved before they are published