The QRD1114 Phototransistor Output Photo Trans with Optical Switches and Reflective is manufactured by ON Semiconductor. It is a reflective optical switch that uses phototransistor output photo transistors for sensing and converting reflected light from object surfaces such as white paper, glass, fabric, etc. into a useable signal. It features a small symmetrical 4-pin package with an integrated optical position sensing element and reflective element. It's typically used for low power applications such as position sensing, object detection, presence sensing, and proximity detection. The QRD1114 is a low-cost, light-to-digital/analog converter that can detect small amounts of reflected light. Furthermore, it also offers a consistent response over the full range of environmental conditions. It comprises of an integrated photo device which is composed of an emitter and sensor with an optimized optical design for enhanced performance. The device is capable of detecting objects from 1.5mm to 10mm away and delivers a wide dynamic range. It is effective in applications requiring DC or AC coupling, and comes with a stable sensing.