HDPE fresnel lens technology 

HDPE fresnel lens technology The Fresnel lens, simply say to be in the lens side have equi-distant tooth tattoo. Through these tooth tattoo, can achieve to specified spectrum light band tong (reflecting or refraction) role. The traditional grinding optical equipment band-pass optical filters are expensive. The Fresnel lens can greatly reduce costs. A typical example is PIR (passive infrared detector). PIR used widely in alarm. product model 7707-1C 7709-1 7709-1B 7709-2 7709-3 7709-4 7709-4B 7709-5 specification 6*6mm Φ21*15.7mm Φ20.3*16.9mm Φ17*9mm Φ17.8*7.3mm Φ14.6*4.6mm Φ16*8mm Φ15.6*5.8mm focal length 20mm 7.6mm 7.6mm…