What You Should Know About Thermal Imaging Cameras

What are the main uses of thermal imaging cameras? While most people have a general idea of what a thermal camera does, not many know how functional it can be.

Although regular CCTV cameras can protect homes and businesses by day, thermal imaging cameras use thermography to provide security long after the sun has set and this is when criminals take advantage of the dark.

Additionally, the thermal imaging camera is a lot more than just an after-dark camera. And there’s a lot more you need to know about your options before deciding which security camera system is suitable for you.

What is a Thermal Imaging Camera?

Thermal imaging cameras or thermogenic cameras (TIC) are handheld devices that include an LCD and use infrared thermometers to detect heat energy from surrounding objects. Users can use these devices to detect potential security risks, including unauthorised vehicles and people.

The camera can generate a picture of the object it detects with the object’s temperature gradient represented. If the thermal imaging camera has MSX technology, it has two cameras (visible light and a thermal imager). When the device takes an image, it simultaneously presents a visible image and a thermal image.

Thermal imaging cameras CCTV aren’t only used for security but in business too. Let’s consider the FLIR C3-X; a Wi-Fi capable non-contact compact camera used to inspect HVAC/R, buildings and electrical systems.

The second thermal imaging camera UK used for similar is the FLIR C5 which offers a combined visible-light inspection camera and infrared manager with an LED torch and wi-fi connectivity.

The FLIR C5 is most often used for finding hot fuses, plumbing issues, and air leaks. The cameras on the FLIR range come with the connector and adapters required to run and charge the units as needed.

How do Thermal Cameras Work?

An infrared thermal imager detects heat energy. The major component of a thermal imaging camera is the heat sensor attached to the thermographer’s lens. This sensor is adapted to work with standard digital camera image capturing technologies. The science behind it allows the device to detect body temperature, surface temperature, and areas where sources of heat energy are wasted. In a building inspection, wasted energy sources include possible thermal insulation gaps and overheating components.

Thermal imaging cameras CCTV create pictures from heat instead of visible light like the regular digital camera. Both light and heat form part of the electromagnetic spectrum, but it’s essential to know that cameras that can detect thermal energy cannot see visible light – and of course, it works the other way around too.

When you point a thermal imaging camera at an area, the sensor provides a view of the infrared spectrum that is typically invisible – this exists between microwaves and visible light at wavelengths. Users can do video recording in colour or black-and-white.

The lens fitted must permit infrared frequencies for the thermal imaging camera to detect and measure infrared radiation and provide diagnostics. These frequencies are then detected and read by a special sensor array.

The sensor array consists of a set of pixels on a grid. These pixels respond to the infrared wavelengths and convert them to an electronic signal. The resulting signals get processed within the body’s main camera unit, where they are converted (employing algorithms) into a colour map presenting temperature values and presented on the screen as follows:

  • Red/orange/yellow – warm regions.
  • Purple/blue/green – cool regions.

A thermal imaging camera can provide the data needed to an external source using USB-C adapters or Wi-Fi. And, of course, users must carry out accurate calibration of the theorem camera to correlate what the camera sees with known temperatures – this ensures radiation detected is accurately measured by the camera.

In addition, some businesses opt for thermal automation cameras to monitor processes in industries to help avoid expensive system failures, malfunctions, and mistakes from burdening finances and overall business productivity. And in some sectors, clamp meters combine thermal imaging with electrical measurement to transform the camera into a powerful inspection and monitoring tool.

The battery power of each thermal imaging camera on the market will depend on the brand of camera, the unit’s battery power and, of course, the chargers you use with the device.

Types of Thermal Imaging Cameras

There are three basic types of infrared imaging cameras: short wavelength, mid-wavelength, and long wavelength.

  • Short wavelength thermal imaging cameras: thermal imaging cameras that are short wavelength can capture infrared in the 0.9 to 1.7 microns range. As high-resolution cameras, they offer exceptional detail and shadow contrast, especially when compared to the visible light spectrum.
  • Mid wavelength thermal imaging cameras: mid wavelength infrared cameras are commonly used for capturing high-temperature readings. They are most often used to scan boiler applications and capture infrared wavelengths between 2 to 5 microns. Of course, these wavelength cameras offer higher accuracy and resolution than short-wavelength cameras.
  • Long-wavelength thermal imaging cameras: Long wavelength thermal imaging cameras are a good choice for highly detailed images. They can capture infrared wavelengths in the 7 to 12 microns range.

Uses of Thermal Imaging Cameras

Thermal imaging cameras play a role in many different scenarios, applications, and industries. For example, they have a role in navigation, military surveillance, cancer detection, and reading skin temperature, to name a few.

Below, we look at some of the many uses of thermal imaging cameras.

Thermal cameras for drones

Thermal imaging cameras are now being combined with drones to serve many purposes. In the past, low-res standard digital cameras with video recording capabilities were the norm. Nowadays, high-accuracy, top-quality thermal cameras are a top choice for private industry and government applications.

Drones with thermal imaging cameras are now routinely used for the following functions:

  • Search and rescue (emergency response)
  • Tactical military applications
  • Livestock monitoring
  • Agricultural management
  • Aerial photography
  • Solar plant performance
  • Roof and building inspection
  • Infrastructure inspection (bridges)
  • Detection of thermal runaway switches on electrical supply lines.

In 2015, the first drone thermal imaging camera (the DJI Zenmuse XT) was created by FLIR Systems and DJI – two companies combining their infrared imaging and aviation system knowledge.

In addition, certain drone companies have really gotten on board with thermal imaging cameras, including Auto Robotics, Parrot, and Yuneec.

Thermal cameras for fire detection

When detecting fire and heat, long-wavelength thermal imaging cameras are a good choice. Fire detection works on longer wavelengths of infrared emitted by surfaces and objects with high temperatures.

Thermal imaging cameras can “see” through smoke and determine the source of fire and heat. An infrared thermal imager detects a rise in temperature and possible hotspots before it ignites, providing the opportunity to be proactive about fire risk management and reaction.

Infrared thermal imagers and thermal imaging cameras play a significant role in the risk management and safety of the following:

  • Rescue efforts for survivors (fire fighting)
  • Factories
  • Wood processing plants
  • Detection of underground fires (mining industry)
  • Detection of fires in cavity walls
  • Recycling plants
  • Waste processing plants
  • Biomass facilities
  • Energy facilities

Thermal cameras for Apple & Android devices

Newbies to the world of thermal imaging cameras will undoubtedly come across various options available for mobile use. For instance, the Fluke range offers a compact camera that can be used to quickly scan building systems, HVAC, process control equipment, motors, electrical equipment and pumps for hot spots.

A compact thermal camera is readily available for most iOS and Android devices, but these pale in comparison to professional thermal imaging cameras. Mobile thermal imaging apps are just simulations. If you’re looking for a high-quality experience, you can opt for thermal imaging with an auxiliary thermal camera device that can be attached to a mobile handset and be controlled and monitored via touchscreen.

The FLIR One Pro is a popular choice for Android and Apple devices. The FLIR One is a lightweight device that can transform a mobile device into a powerful thermal infrared camera. The device displays live thermal imagery using the associated FLIR app, and you can then measure variances in temperature, record thermal videos and images, and take advantage of the MSX technology to blend visible light and thermal for high-resolution image results

Thermal cameras for wildlife

Wildlife thermal imaging camera applications play a major role in terms of wildlife monitoring and managing. IR cameras for wildlife have specific requirements; for instance, they need to be quiet (or silent), be able to withstand the elements, and offer high-resolution thermal functionality regardless of vegetation, darkness, rain, fog, and an animal’s camouflage.

When it comes to hunting, most users pair their thermal cameras with a high quality monocular, a must-have piece of hunting equipment. This is a thermal spotter allowing you to clearly see objects so that you don’t waste a shot or so that you can make a clean shot without getting too close in the range of a predator or other danger

Several IR cameras on the market are used for wildlife applications, including the FLIR Scout TS-Series, FLIR Scion OTM (with rugged IP67-rated housing and intuitive controls), Pulsar Axion Key XM30, FLIR Systems Ocean Scout 240, FLIR Systems Scout III 640, and FLIR Systems Scout TK Mini

The function of thermal imaging cameras in wildlife includes:

  • Photography
  • Environmental monitoring
  • Animal tracking
  • Wildlife conservation
  • Animal rescue
  • Scientific investigations

Thermal imaging for marine cameras

IR cameras have exceptional use in the marine environment. Being on the water or heading to the seaside seems like a lot of fun, but not when it’s dark, visibility is poor, and something potentially goes wrong. You may encounter challenges heading into a harbour or port, or your vessel may collide with another vessel. In some instances, marine vessels have passengers overboard.

Thermal imaging cameras are ideal for short to medium range detection of objects floating on the water, other vessels, traffic bouts, bridges, and even people who may have met with an accident in the water and need help when visibility is poor.

FLIR has produced a wide range of thermal imaging cameras that are purposed for shipboard security, man-overboard scenarios, anti-piracy efforts (safety and security), severe weather detection, HVAC system monitoring, and nighttime navigation. The Teledyne FLIR range is also worth investigating if quality and value for money are a priority.

Interestingly, thermal imaging cameras can be used during the day in marine applications because they are not affected by the sun’s glare and allow users to see through the marine haze.

Thermal security cameras

Thermal imaging cameras have made a name for themselves in the security sector. Law enforcement uses thermal security cameras regularly to locate, track, and capture criminals in the UK. However, regular CCTV systems and inspection cameras aren’t good enough in poor weather conditions, woodlands, and dense foliage. Thermal imaging cameras are the difference between criminals getting away and getting caught.

For security and law enforcement purposes, thermal cameras can also be used in daylight as they can provide an image of heat when someone is possibly hiding behind foliage or trying to conceal themselves in the vegetation. But, of course, these IR cameras truly shine when used in low-light or pitch dark conditions – criminals may be able to hide, but an IR camera will detect their heat

Of course, thermal imaging for law enforcement and security doesn’t have to be done on the ground. It can be used from the air too. For example, aircraft can incorporate infrared cameras, which can aid in tracking criminals on the ground who are on the run.

You can get a security IR camera in two forms:

  • CCTV mounted thermal imaging
  • Handheld thermal cameras used to scan the environment

Traditional CCTV cameras have been useful in thwarting crime, but thermal cameras take it up a notch. While traditional CCTV systems can monitor well during the day, they need to be installed in a well-lit area by night. Thermal imaging cameras used for CCTV can be used for day and night surveillance.

Most modern thermal cameras used for security also include smart sensors and analytics. Smart sensors can detect the differing temperatures of surfaces, objects, and beings. When a smart sensor is paired with analytics provided, it enables management to make quick decisions regarding safety or reaction with confidence.

Night vision cameras

Many people get night vision cameras and IR cameras confused. IR cameras use thermography to create an, which means that they read the temperature, whereas night vision cameras use light to create an image. Let’s break down the difference between these two camera types:

  • IR cameras – FLIRs create images from heat, not light. IR or thermal cameras don’t just detect heat but varying degrees of heat and then present them in different colours.
  • Night vision cameras – night vision uses infrared light to illuminate images in darkness. While infrared light is invisible to the naked eye, it is all around us. IR cameras use technology to detect infrared wavelengths to enable the camera to show images in the dark.

Industrial infrared cameras

Many industrial businesses use thermal imaging cameras for building inspection, safety and system monitoring. If you’re running an industrial setup, it is best to invest in IR cameras certified specially for industrial use.

Certified for industrial use infrared camera systems offer various different configurations and abide by certain manufacturing standards applicable in the UK, depending on the application and environment the camera will be used in.

For instance, you would want to use a specialised IR camera in an underground mining application where explosive gasses are used. This means that mining and petrochemical industries, for instance, need infrared cameras that are certified for industrial use in those particular environments.

Another example is in environments where the dust particle density is high – you would need a thermal imaging camera that can handle the environment and still work accurately regardless of the challenges.

Industrial thermal cameras include unmanned cameras (drones), handheld devices, and fixed-mount units. Some examples of when industrial IR cameras may be needed include mining, automotive, sugar processing, fire fighting, and high voltage testing, to name a few.


Can Thermal Imaging Cameras Benefit Your Business?

Thermal imaging cameras provide a non-invasive inspection technique on buildings and systems. Then ensure quicker fault detection and help businesses avoid costly repairs and maintenance tasks.

The camera ensures inspection of equipment and setups doesn’t disrupt production. You can expect fewer false alarms, and visibility isn’t deterred by light conditions and other objects. All in all, thermal imaging adds exceptional functionality to any business monitoring, security, and even maintenance system.

What is emissivity, and how is it related to infrared temperature measurements?

The dictionary definition of “emissivity” is as follows: “The relative power of a surface to emit heat by radiation: the ratio of the radiant energy emitted by a surface to that emitted by a blackbody at the same temperature.”

In simpler terms, it measures a surface’s ability to emit infrared energy. It forms a key part of measuring temperature reliability with a thermal imaging camera or an infrared temperature sensor. Emissivity plays a role in thermography. It depends on several important factors, including the finish of the surface, the material, the sensor’s wavelength sensitivity, and the measuring arrangement.

High, constant emissivity can be seen with non-metallic objects regardless of the surface finish they have. This is most often seen when using a long-wavelength infrared camera.

On the other hand, metals tend to have low emissivity depending on the material’s surface finish. When using an IR camera, it is interesting to note that when the wavelength sensitivity of the sensor is increased, the emissivity drops. Because emissivity is variable and possibly low with metals, a short wavelength sensor is recommended.

The smart sensor used is typically determined by the required measuring temperature range. For low temperatures, sensors with sensitivity to wavelengths of 1.6µm, 2.3µm and 3.9µm are required.

For very high temperatures, it’s recommended to use wavelengths of 0.5 to 1.0µm. As a point of interest, an infrared thermal imager with a sensor sensitivity of 1.0µm wavelength can measure up to a whopping 1800°C.

What should I consider about my application when selecting an infrared camera?

What thermal camera is best?

The answer to this question all depends on your specific application. While there are many high-quality infrared camera options available, you can’t just go out and buy any unit and expect it to work perfectly in your application.

Choosing the IR camera is essential if you want to ensure ultimate functionality. Critical considerations to make when choosing an infrared thermal imager include:

  • The target size and distance – this is called ‘field of view.’
  • Mounting options and limitations – fixed mount and handheld portable options available.
  • Atmospheric effects or transmission through surfaces – this is called ‘spectral response.’
  • Type of surface in question – this impacts emissivity and the type of sensor selected.
  • Response time.
  • Required signal processing.
  • The environment you’re working in (mine, processing plant, factory etc.).

Which Infrared camera is right for my application?

Choosing the right thermal imaging camera UK for your application can seem tricky if you don’t know what you’re looking for. In most instances, buying an IR camera with the highest detector resolution (this is image quality) that you can afford within your budget is recommended.

Spend time working with testers to ensure you’re selecting the right camera for you. You will notice that IR cameras have fewer pixels than regular digital cameras that work on visible light. This makes it important to note the detector resolution offered.

A higher resolution means that the infrared camera can measure a smaller object from a greater distance while creating sharp thermal images. This ensures accuracy and reliability.

Note that the detector resolution is entirely different from the display resolution, so don’t get confused when you read that the LCD resolution is high. You need to look specifically for the detector resolution, as this is what matters most when choosing the right infrared camera for your application.