The “brains” of this system is the VCNL4020, an integrated proximity sensor. Located 22 mm to the left and right of the VCNL4020 are a pair of VSMF2890RGX01 infrared emitters. To view a video demonstrating this concept visit http://www.vishay.com/videos/optoelectronics/proximity-and-gesture-sensor-demo-kits.