In long range monitoring applications such as coastal defense and anti uav, we often encounter such problems: if we need to detect 20 km people and vehicles, what kind of thermal imaging camera is needed, this paper will give the answer.

In the infrared camera system, the observation level of the target is divided into three levels: detectable, recognizable and distinguishable.

When the target occupies one pixel in the detector, it is regarded as detectable; When the target occupies 4 pixels in the detector, it is regarded as recognizable;

When the target occupies 8 pixels in the detector, it is regarded as distinguishable.

L is the target size (in meters)

S is the pixel spacing of the detector (in micrometers)

F is the focal length (mm)

Detection target range = L * f / S

Recognition target distance = L * f / (4 * s)

Discrimination target distance = L * f / (8 * s)

Spatial resolution = S / F (milliradians)

If the object to be detected is UAV or pyrotechnic target, it can also be calculated according to the above method.

Usually, thermal imaging camera will work together with long range IP zoom block camera module and laser ranging, and be used for heavy-duty PTZ camera and other products.