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Objects in nature, in addition to the visible light image we are familiar with, also have an infrared thermal radiation image, but infrared rays are not visible to the naked eye because it is invisible light. The magic technology of "infrared thermography" converts thermal radiation images into visible light images, which allows people to see things that were invisible in the past. The device that implements this conversion is called a thermal imager, and through this thermal imager, we can see the sight of the day in the dark night.

Resolution
Resolution is one of the most important indicators of night vision thermal imagers, and night vision is one of the keys to the cost of night vision thermal imagers. The resolution of a typical night vision thermal imager is 160x120, 336x256 and 640x480. Prices range from tens of thousands to hundreds of thousands.

Built-in screen resolution
We observe the target through a night vision thermal imager, essentially observing the LCD screen inside it. The top-of-the-line night vision thermal imager has a very high resolution and clarity of the built-in screen for clearer viewing and better visibility.

Double or single cylinder
The double cylinder is significantly better than the single cylinder in terms of comfort and observation. Of course, the price of the dual-tube night vision thermal imager is much higher than that of the single-tube night vision thermal imager. The double cylinder night vision thermal imager will be much more productive than a single cylinder.

Magnification
Due to the technical bottleneck, the physical magnification of the night vision thermal imager, most of the instrument's magnification is only within 3 times. At present, the maximum production rate is 5 times.

External recording device
Night vision thermal imager, well-known brands will provide external recording device options, which can be directly recorded to the SD card through this device. And remote shooting can also be taken by remote control.