Contactless turning on of IoT devices using mobile phone camera light source

摘要

Method and system for turning on an IoT device directly in a contactless manner using a mobile phone with a camera light source and an app is disclosed. A photo sensor unit is provided on top of the IoT device for converting the incident light from mobile phone into authorized and authenticated power-on switching command to the IoT device. The photo sensor unit can be a first photosensitive circuit, a second photosensitive circuit, or a third photosensitive circuit, which includes a photodiode, a photo resistor, and an amorphous silicon solar cell, respectively. The photo sensor unit is coupled to a power-on circuit of the IoT device, and used for detecting an intensity of incident light and assessing whether a voltage difference produced by the incident light exceeds a power-up voltage difference threshold value, and if so, awaking the IoT device to be power-on, otherwise, maintaining the IoT device to stay powered off.