主动式红外探测器的设计
Design of active infra-red detector
室外选用主动式红外探测器，主动红外发射器发出一束经调制的红外光束，投向红外接收器，形成一条警戒线。
Selection of active outdoor infrared detectors , active infrared transmitter sent a bouquet of the infrared beam by the modulation , into the infrared receiver to form a cordon .
主动红外探测器