This sensor uses infrared technology to detect an object at 5mm by determining the difference between low reflective conditions (i.e. black) and high reflective conditions (i.e. white).
The 33370 sensor consists of an infrared emitting diode and an NPN silicon phototransistor mounted side by side on a converging optical axis in a black plastic housing. The phototransistor responds to radiation from the emitting diode only when a reflective object passes within its field of view. The area of the optimum response approximates a circle .5mm in diameter.
Comes packaged with a 60cm Sensor Cable.