How Do Infra-Red Cameras Work

Infrared cameras work using infra-red radiation. It is a type of magnetic radiation whose wavelength is longer than that of visible light. This wavelength cannot be seen through naked eyes. What an infra-red camera does is that it detect the heat and convert it to an electrical signal resulting in an image. Let’s take a deeper look into it.

How Does It Work?

An infrared camera has an optical system that grabs infrared energy and focuses it on a detector chip (sensor). Every detecting pixel in the sensory array reacts to the infrared energy and gives out an electrical signal.

Now what the camera processor does is that it takes each signal and applies a mathematical formula to it, which results in a color map. Every temperature is given a different color, and the resulting matrix produces a thermal image.

Thermal Cameras

They are made up of either cooled or uncooled infrared detectors. Cooled give better images in terms of quality and precision, whereas uncooled are expensive and less precise image-wise. However, cooled detectors always work with cryogenic coolers. The temperature is lowered to a cryogenic level and reduces heat-induced noise than the signal emitted at the scene.

Uncooled image detectors do not need cryogenic cooling devices. They work with a microbolometer device – a bolometer sensitive to infrared radiation.
You may think that infra-red cameras will help you see through the walls or other solid objects, but that is not true. These cameras can only take up heat energy emitted from objects, even a wall.

Infra-red Spectrum

The infra-red or IR spectrum is categorized into 4 regions:

  • NIR – near infra-red
  • SWIR – short wave infra-red
  • MWIR – medium wave infra-red
  • (V) LWIR – long-wave infra-red

Do Thermal or Infra-red Cameras Produce Image during Day Time?

Yes, they do; the camera and imaging focus on heat released and not reflections or any other rays; therefore remains unaffected in visible light and works as well in the day as nighttime.

4 Common Issues with an Infra-red Thermal Camera

Infra-red Camera Night Vision Detection

Night vision imaging issue is mainly caused because of the angle and function of the infra-red lamps. They work on peak waves of 850, and angles between 5 to 60 degrees can be used. When the IR tube is smaller, the irradiation distance is further increasing the flashlight effect that causes image distortion.

Fogging Troubles

Generally, the infra-red cameras are sealed in this type of design with a protection level up to IP66. However, the infra-red lamp will start working and produce excessive heat, and if the machine itself is not sealed properly, the vapor effect will distort the image. Some users or manufacturers may use an inert gas such as nitrogen for the reduction in water vapor.

IR Day Time Camera Off-Color

You must weigh the pros and cons before installing a security system. Investing in a good quality camera is essential. Any off-the-rack cheaper alternative will result in daytime off-colored images, and the reason behind this is a camera filter.

Heating Issue of The IR Camera

The infra-red camera has its distinct configuration, which generates heat; if it is not properly covered or insulated, it may spread to other parts resulting in dysfunction.
If you have finally decided on investing good security system and are in search of quality products, have a look at our Opto-series for Infra-red cameras, or call 281 438 3500 for an expert’s opinion.

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