(WHTM) — With the manhunt for Danelo Cavalcante now over, law enforcement officials say they used many different methods to find the missing fugitive. Pennsylvania State Police used helicopters, drones, K9s, and even thermal imaging cameras.

So how do those cameras work?

By definition, a thermal camera is a non-contact device that detects infrared energy (heat in this case) and converts it into a visual image.

According to inferred camera company Teledyne Flir, thermal cameras do not work like regular photo cameras. Photo cameras use visible light energy that hits something and a detector receives the reflected light, which in turn becomes an image.

Thermal imagers take photos of heat. Both heat and light are on the electromagnetic spectrum.

Inside a thermal camera is a lens, a thermal sensor, electronics, and then the housing where all of the technology is kept.

Resolutions of thermal cameras, according to Teledyne Flir, are at a much lower resolution than a regular photo camera. This is because thermal detectors need to sense the energy that has much larger wavelengths than visible light, which then requires each element of the sensor to be very large.

The company states that heat sensed by the infrared cameras can be very precise, as small as 0.01 degrees Celsius in some instances.

Thermal cameras can be used for a variety of things. For example, building inspections firefighting, autonomous vehicles and automatic braking, skin temperature screening, industrial inspections, and manhunts, when it comes to finding escaped prisoners such as Cavalcante.