Non-Contact Touch Switch ( Infrared Touch Pad)
We currently use a non-contact hand sensor for neurophysiological recordings based on infrared proximity sensors. The infrared (IR) touch pads are based on commercially available reflective IR sensors (Omron EE-SB5VC). We operate the sensor at 5 V (Vcc) and use a limiting resistor of at least 150 ohms and a load resistance (pull-up) of 1K. The window of the sensor is fitted to a 1" x 0.5 " x 0.5" machined aluminum block. This shape was selected to mimic earlier electrical contact sensors. The sensor is recessed and protected by an optical quality clear acrylaic disc. The sensor and its aluminum block are screwed into a black Delrin plate. A few photographs are shown below.
3 pad infrared touchpad mounted on 1" structural tubing
Closeup of touchpads
Wiring and protective cover on bottom side