An infrared thermometer uses IR technology to detect heat level which makes it so handy for everyday use. We’ve all have probably seen or used an infrared thermometer at some point in our lives.
Even if you managed to live without seeing, thanks to Covid-19 you’ve probably been held at an infrared thermometer point (see, what I did there!) in front of a gate somewhere.
Yes, that little gun thingy is an infrared thermometer to measure your hotness; I mean your body temperature!
There are so many applications for infrared thermometers. In this article, I’ll be attempting to list them with a bit of why and how about the application.
But first, as always, we’ve got to know how the machine works, isn’t it? If you already have an idea, scroll down to the main part.
What Is an Infrared Thermometer?
It’s a type of thermometer that uses infrared radiation to measure the temperature of any object. Sounds complicated? Well, it’s not.
Every object we know of emits thermal radiation i.e., it releases temperature. Your infrared thermometer picks up this radiation and measures the heat from it.
And the frequency of this radiation falls in the category of infrared light, hence the name.
How Does an Infrared Thermometer Work?
An infrared thermometer works by taking in the thermal radiation emitted by any object and transferring it onto a thermopile sensor. From there on, this thermopile translates the thermal energy into an electrical output which is what we see on the display.
The device is fitted with a lens to concentrate on a specific spot. This lens funnels the infrared light or radiation into the thermopile sensor. You could make an IR thermometer without this funneling mechanism. But it makes the readings more accurate.
You may have also heard of this thermal radiation as black-body radiation.
Sometimes an infrared thermometer is fitted with a laser to make it easy to aim at an object which is why you might have heard of it as a laser thermometer.
Different Types of IR Thermometers
Based on the same working principle, infrared thermometers can be of many types. 3 types are particularly seen in use. They are,
Spot Infrared Thermometer
When you want to check the temperature of a specific spot on a surface, you’ll use a spot infrared thermometer.
Infrared Scan Thermometer
This is used to check the temperature of a larger area. You could say it’s a type of spot thermometer, but it also uses a rotating mirror to scan the whole area.
Infrared Thermometer Camera
These are essentially infrared thermometers. They measure the temperature of an area by taking point-based temperatures, thus creating a two-dimensional thermal image.
7 Uses of Infrared Thermometer
With all those variations of this thermometer, it has become a necessary tool for various applications. Here are the common places where you can use an infrared thermometer.
1. Taking Body Temperature
This has to be mentioned at the very first since we’re living in the covid-19 era. From February 2020 until now, IR thermometers have been one of the main segments of entry checkpoints everywhere.
Although it’s proven to be less accurate than other forms of measuring body temperature, the contactless method makes it the obvious choice. FDA-certified IR thermometers are reliable.
The handheld thermometers are chosen because they have no cross-contamination risk. They are quickly getting known as forehead IR thermometers.
However, you’d want to buy a medical-grade and certified thermometer. The industrial-grade IR thermometers won’t be of much use to you.
2. Automotive Sector
The engineers in the automotive industry heavily use infrared thermometers to sort out weaknesses and other problems in different parts. Using spot infrared thermometers, you can check whether a part has any weak spots by measuring the temperature of the whole area.
If it shows an uneven temperature curve, then most likely, this part won’t make it to the final phase.
An infrared thermometer is vital in a factory environment where you can’t reach certain areas due to danger or obstacles.
Taking instant temperature after running an experiment is a perk of using such thermometers.
3. Production Plant
IR thermometers are well-suited for all kinds of manufacturing plants. It has become an essential tool for the production process.
Do you need to check the equipment condition after weeks of operation?
You use an infrared thermometer to check whether or not the machine is working above its recommended temperature. Sudden temperature rise could be a tell-tale sign of failure for mechanical parts.
The whole assembly line’s quality can be quickly checked before the start of a production week.
4. Home Use
IR thermometers might not have a lot of use for many households. But for certain households with many electronic machines such as computer workstations, a server, or anything as such will find it monumental to have an IR thermometer close by.
And if you’re someone who constantly has a DIY project at hand, you’ll find yourself using this device more often than not.
5. Cooking
You might not think that IR thermometers can be used in cooking. I agree that it’s a bit unconventional since most people use probes to check the temperature of the meat.
Indeed, you can’t tell whether or not a steak reached its proper internal temp. However, you could tell if your dish is still hot enough to be served to your guests at the BBQ party.
6. Agriculture
You can use an IR thermometer to check the temperature of your animal’s bedding. That way, you can tell whether or not it needs changing. You can also check the temperature of your plant leaves to observe their health.
7. Gardening
Having cold soil could be detrimental to your plant’s health. While the air may be warm, the soil could still be cold. Although you have to use a probe to check the internal soil temp, you can check the temperature of the soil surface.
Limitations of Infrared Thermometers
Since these infrared thermometers use infrared rays to detect heat, it also carries the same limitations of infrared rays. Here are a couple of them,
- It can only measure the surface temperature of any object
- Due to emissivity, it needs adjustments each time you change the object
- Not as accurate as probes
- It’s affected by the weather and environment such as frost, moisture, and fog, etc. though temporarily
- It’s affected by rapidly changing ambient temperature
- It can’t check through glass or plastic or any liquid
Different Forms of Infrared Thermometers
Infrared thermometer devices come in all sorts of forms. Some devices have infrared thermometers incorporated in the design. So, you might not even know that you’re using infrared thermal detection.
Here are some common forms of Infrared Thermometer Device,
Handheld Laser Thermometer
This is the most common type of IR thermometer you’ll see around you, especially since we’ve been hit with Covid-19. You can measure the temperature of objects or persons from a distance.
Pocket Infrared Thermometer
These are made to be compact devices. Some are so small that you can put them in your pocket.
Infrared Thermocouple
This is not used as a standalone thermometer. It’s a sensor that needs to be attached to electronic circuitry to give output.
Fixed Mount IR Thermometers
This is the opposite of handheld thermometers. It’ll be stationed at someplace to constantly measure the temperature of passing objects.
Two-Color Ratio Thermometer
It uses the exact principle of a simple IR thermometer. But instead of showing the temperature of a single object, it measures the temperature of two different infrared or thermal radiations and delivers their ratio.
Frequently Asked Questions
Can you measure water temperature with an IR thermometer?
Yes, you can measure the water’s temperature with an infrared thermometer but only the surface of the water. The laser of a thermometer passing through the water doesn’t mean it can measure the internal temperature.
Can you measure ambient room temperature with an IR thermometer?
Yes, you can measure the temperature of your room with an infrared thermometer. However, will it be an accurate measurement? Not likely.
Can an infrared thermometer measure temperature through glass or plastic?
No, it can’t since infrared thermometers cannot measure temperature on the other side of glass or plastic.
Are handheld infrared thermometers safe?
Yes, these thermometers are safe to use on everyone, including children, babies, and elderly citizens, as long as you don’t point the laser beam into the eyes.
How do I know if my infrared thermometer is working properly?
Easy! Take a heated object that you know the surface temperature of and measure it. If it matches, then you know it’s working well.
Are forehead IR thermometers accurate?
Forehead thermometers are only supposed to let you know whether or not you have a fever. But a 2020 study tells us that it’s less accurate than all other forms of reading temperature.
Final Words
An infrared thermometer uses the most basic technology, a simple thermocouple which transforms heat data into digital signals. You might not even know but you’re using this technology in your home.
The smoke detector in your house uses a type of IR thermometer. Some of the newer smartphones also come with an infrared thermometer built in them.
It has its limitations, as you saw. Being a non-contact device, it fails at providing better accuracy than probes that reads temperature through contact.
However, as we’re going contactless day-by-day, I reckon we’ll be using more of these in the coming days.