Description
A phototransistor is effectively a transistor that responds to light. This specific phototransistor has a built in infrared LED and works really well as a reflectance sensor. It is ideal for detecting the difference between black and white surfaces or general object detection up to 10mm.
To use this phototransistor a simple current limiting resistor rated at 330 ohms is required on the infrared LED side with a 10K ohm resistor as a pull up on the transistor side.