What Is a Cold Mirror?

The cold mirror , as opposed to the hot mirror , is also known as an infrared transmission filter , an IR pass filter , an IR filter , and a visible light reflection filter.

Cold mirror

Right!
Cold mirror
The cold mirror reflects visible light and allows infrared or heat sources to penetrate. Colored optical glass-infrared transmissive sheet, with low surface reflection, can be applied to infrared devices or automated detection equipment, allowing the sensor to receive only infrared signals
LCD projector infrared sensing application
Cold light source application
Night (infrared) surveillance applications