The family of Reflective Sensors from ON Semiconductor consist of an infrared emitting diode and an NPN silicon photodarlington mounted side by side in a black plastic housing. The photodarlington responds to radiation emitted from the diode only when a reflective object or surface is in the detector’s field of view. The features include phototransistor output, no contact surface sensing, unfocused sensing of diffused surfaces, compact package, and daylight filter. Applications include Medical Electronics/Devices, Automation, Test and Measurement, and Building and Home Control.