You have asked the core of this question, understanding the principle can better understand its advantages! The core principle of thermal imaging night vision devices is to detect the infrared radiation (heat) emitted by the object itself, rather than relying on visible light, and ultimately convert invisible thermal signals into visible images.

The entire process is mainly divided into four key steps, from receiving heat to generating images to form a complete chain.

1. Receive infrared radiation (heat)

All objects with temperatures above absolute zero (-273.15 ℃) will continue to radiate infrared radiation outward (an invisible light that essentially reflects the energy of molecular thermal motion of the object). The lens of the thermal imaging night vision device collects infrared radiation from the target and environment, and focuses it on the core detection component.

2. Conversion heat signal

The focused infrared rays will be projected onto the infrared detector array (core component, similar to the photosensitive element of a camera). The detector will convert the received infrared energy (heat) into corresponding electrical signals, and the higher the temperature in the area, the stronger the electrical signals generated; The lower the temperature, the weaker the electrical signal.

3. Processing electrical signals

The original electrical signal output by the detector is very weak and needs to be integrated. The signal processing unit inside the device amplifies, denoises, and corrects these electrical signals, converts them into digital signals, and assigns different "image grayscale values" or "color values" based on the strength of the signal (corresponding to temperature).

4. Generate visible images

Finally, the display unit (such as screen, eyepiece) will combine different grayscale/color pixels based on the processed digital signal to form a thermal imaging image visible to the human eye. There are two common display modes: one is "grayscale mode" (bright areas represent high temperature, dark areas represent low temperature); The second is the "pseudo color mode" (using warm colors such as red and yellow to represent high temperatures, and cool colors such as blue and purple to represent low temperatures), which makes temperature differences more intuitive.

Simply put, it is equivalent to taking a thermal photo of an object. Even in completely black, smoky, or hazy environments, as long as there is a temperature difference between the object, it can be imaged. This is also the core difference between it and traditional night vision devices that rely on low light.