Abstract: Pyroelectric infrared sensors are widely used in air conditioning, and the decorative materials have a great influence on the actual detection distance. The infrared transmittance of the material was characterized by the characteristic infrared (9.5 µm) of human body radiation, and compared with the actual infrared detection distance of the sensor. High density polyethylene (HDPE) was used as the main material to prepare the covering film of the sensor. The lower the transmittance of the material at 9.5 μm wavelength, the shorter the actual detection distance of the sensor. Infrared transmittance can effectively evaluate the infrared penetration performance of materials, which has a good guiding significance for the development of infrared penetration materials.

Key words: Infrared wave radiated by human body, High density polyethylene, Infrared transmittance