This sensor is designed for phone has two functions. The first function is the detection of the spatial light (ALS) and using the software for adjusting the brightness of the backlight automatically adjusts the brightness of the backlight of the phone according to the current ambient light. The dim lighting of the backlight protects your vision, and can achieve battery savings.
The next function we call the shooting function zoom (PROX), the use of internal reflection infrared LED emitter the role of the sensor and the built-in PDS receiver to determine whether the phone is during a call near the face and this will determine the status of the backlight of the buttons on the touch screen.
1x TMD27713 sensor face detection for a short distance and lighting for arduino