Vishay VCNT2025X01 Reflective Optical Sensor is a reflective sensor in a miniature SMD package. It has a compact construction where the emitting light source and the detector are arranged in the same plane. The operating infrared wavelength is 940nm. The detector consists of a silicon phototransistor. The sensor analog output signal (photocurrent) is triggered by the detection of reflected infrared light from a close-by object.