As a reflective sensor, the VCNT2030 package includes an infrared emitter and phototransistor on the same plane. Light is emitted and if there is an object in range, reflects onto the phototransistor. For example, if the forward current of the emitter is 8 mA, and an object is 1 mm away, the output is 2.5 mA. In this example, the object only reflected 20% of the infrared light; a Kodak gray card. What is unique about the VCNT2030 is that the emitter is a Class 1 Vertical Cavity Surface Emitting Laser (VCSEL).