Understanding the basics of thermal imaging systems (FLIR).
Thermal imaging systems (FLIR Forward Looking Infrared Radar) are based on a variety of different sensor technologies that give the user a visual representation of infrared or “heat” energy. The sensors are made of various materials that react when infrared energy is focused onto them providing an electrical charge. This charge is read by the signal processing electronics and is then converted into an image that can be displayed on an LCD screen. This image can be quite detailed showing differences in temperature of as little as hundredths of a degree. Thermal imaging is considered the Pinnacle of Night Vision technologies since it requires zero light to operate and is totally immune to visual light sources.
Thermal imaging systems are completely passive systems in that they emit no energy in order to operate. Unlike some old night vision systems that require an infrared light source to function, the thermal imager utilizes the infrared energy that is emitted by all objects in the universe. Since infrared energy is emitted by everything it is very difficult if not impossible to defeat thermal imaging. In other words you can’t hide from infrared cameras!
Types of thermal imaging systems.
As you can imagine there are many useful applications for a technology that can “see” in total darkness. Indeed, thermal sensors have been integrated into a wide variety of products designed to help military, law enforcement and industrial users. The most common types of systems are the handheld thermal scope and the weapon mounted thermal rifle scope. These units come in different configurations that can be small pocket sized scopes to large long range imaging platforms. Some systems utilize thermal imaging as a part of a handheld binocular targeting system that includes thermal, visual, laser designator and laser rangefinder components. Thermal rifle scopes generally fall into two categories, the stand alone thermal weapon sight and the clip on thermal rifle scope. Stand alone scopes mount to your rifle in the same way that a standard optical scope does. They have a crosshair reticle and a means to adjust for windage and elevation to “zero in” the weapon. Stand alone thermal scopes are a great addition to your rifle but they do require that they be sighted in to a dedicated weapon. The clip on thermal scope is a recent innovation that lets you “clip on” the thermal scope in front of your already “zeroed in” daytime scope instantly turning it into a thermal sight. This was developed for the US Military so that soldiers could go from day to night operations without having to carry two weapons.