Long Distance Switch
This long distance infrared switch has a reflective distance of more than one inch, depending on circuitry. Designated the OPB732 series, the reflective switch configuration includes an infrared LED and phototransistor, and uses an opaque housing to reduce the sensor’s ambient light sensitivity. When infrared light strikes the phototransistor, it becomes forward biased and is considered to be in the “on” state, providing an IC(ON) current proportional to the light striking the phototransistor. When the infrared light from the LED is not reflected to the phototransistor, the device turns “off,” minimizing the IC(ON) current.