Infrared products
2021 10/08
In nature, any object will produce infrared spectrum when the temperature is higher than absolute temperature (-273 degrees). The wavelength of infrared energy released by objects at different temperatures is different, so the infrared wavelength is related to the temperature. There are two key components in a passive infrared detector. One is a pyroelectric infrared sensor (PIR), which can convert infrared signal changes with a wavelength of 8-12um into electrical signals, and can detect white light in nature. The signal has an inhibitory effect. When no one is moving, the PIR senses only the background temperature of the detection area. When the human body enters the warning zone, through the Fresnel lens, the PIR senses the difference signal between the human body temperature and the background temperature. A signal is converted into an electrical signal. The other device is the Fresnel lens. The Fresnel lens has two functions: one is focusing, that is, the pyro-infrared signal is refracted (reflected) on the PIR, and the second is to divide the detection area into several bright spots. Zone and dark zone, so that moving objects entering the detection zone can produce a changing pyro-infrared signal on the PIR in the form of temperature changes.