I need help with choosing the right sensor for a small project.
In my project, I have to sense a hand at about 5-10cm distance and I am not sure about the sensor I should use. The sensor will trigger a switch (relay) and the device will transmit data through bluetooth, etc.
The sensor will be either behind transparent plastic, or if the sensor is small enough I might drill a hole in the plastic and the sensor can be in the open.
I ruled out ultrasound sensors because of the transparent plastic. I am guessing the sensor will not work?
IR sensors are probably the best choice, but which one? I have a few TCRT5000 sensors lying around, but according to the datasheet their max range is 8mm.
Any help would be appreciated.