Visible light communication using the flash light LED of the smart phone as a light source and its application in the access control system

Visible light communication (VLC) is one of the most popular research points of the short range wireless communication. Due to the high efficiency, long lifetime, and fast switching characteristics of LEDs, LEDs are ideal light source for the VLC. In this paper, the flash light LED of the smart phone has been studied and used as the light source for the VLC. The encoding and decoding methods appropriate for the flash light have been proposed and demonstrated. This VLC technique has been applied in the access control system, which is simple, reliable, convenient, and low cost, and can be a supplement to the conventional access control system.