The VCNT2020 with Optical Switches, Reflective, Phototransistor Output Ref Optical Sensor Transtr Output 940nm is manufactured by Vishay. It is a reflective that uses infrared light as the sensor output source. It has a 940nm light emitting diode (LED) and phototransistor output that can detect a signal from the 940nm LED. In addition, it features two optical switches that are used to provide an improvement of the signal or to use its multiple outputs. The optical switches are capable of providing both an open and closed status, for a simple and fast signal routing. The output of the VCNT2020 is a voltage output that is determined by the intensity of the received or reflected signal. This part comes in a convenient TO-39, 4-lead package, which is perfect for any operating environment.