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How Do Thermal Cameras Work

How Do Thermal Cameras Work


How do thermal cameras work. If you've ever seen all the images or videos of a red and yellow mess, it's called thermal imaging technology, generally known as thermal imaging. Here's how thermal camera works.

What is an Infrared Camera?

A thermal infrared camera is camera used for infrared energy detection. Infrared camera turns energy into a signal. A thermal image may be processed by the electronic signal. Main characteristics include resolution, precision and range of temperature.

Thermal imaging is used in all manner of various scenarios—utility and energy providers use it to see if a house might lose heat from door cracks and window cracks. Police helicopters use it to find the criminals in the night. Weather stations are using it to map storms and hurricanes. It is used in the medical profession to detect multiple illnesses and diseases. And certain home surveillance cameras will use it as well.

What is thermal imaging?

In the most simple language, thermal imagery often helps you to see the heat produced by objects. The thermal imager records almost the temperature of the individual objects in the picture, and then applies the color hue to each temperature, allowing you to see how much heat is produced relative to the surrounding objects.

Cold temperatures typically take blue, purple or green shades while warmer temperatures can show red, orange or yellow shades. You will find that this guy, for instance, is covered in red, orange and yellow while the others are blue and purple on the picture on the top of this page. It's because it emits more radiation than the objects around it.

Some thermal imaging cameras use only grayscale. Police helicopters, for example, use grayscale to identify criminal criminals.

How do thermal cameras work

Temperature is detected by thermal imaging cameras as various levels of infrared light are recognized and registered. This light is opaque to the naked eye, but it can be called heat if the temperature is high enough.

Each object emits a form of radiation infrared that is a way to distribute heat. If you place your hands on some hot coals on the barbecue, they will radiate infrared and pass the heat to your hands. Moreover the remainder are a combination of ultraviolets and infrared light and just about half of the solar radiation is released by visible light.

The hotter an object, the more infrared radiation it creates. Thermal imaging cameras can display and transform this radiation into a naked eye image, while the camera collects and transforms invisible infrared light into an image that the eyes can see.

There is a beam of small measuring devices in the thermal imager, called a microbolometer, which collects infrared radiation one for every pixel. The microbolometer records the temperature and then assigns the corresponding color to the pixel. This is why most thermal images have an extremely low resolution in comparison with modern TVs and others. In fact, the very good thermal imager resolution is only 640 x 480.

How Is It Different Than Night Vision?

Thermal imaging can technically be a form of vision at night. But it would be too much if your aim was simply to look into the dark.

For example, it is very good to have a good night vision function in a police helicopter, because people can easily differ from other environments. It not only makes it easier to find suspects in the dark, but also more easy to find people who can blend in with the environment in the broad daylight.

However, most thermal imaging cameras rely on longer infrared wavelengths, and the typical security cams with night vision are can record short infrared wavelengths. Thermal imaging cameras, on the other hand, are capable to capture infrared rays with longer wavelengths in order to detect heat.