I was experimenting with Infrared touch. First I tried to use a normal IR LED, but I got into issues with ambient light. I tried to substract it during calculations, but results were not stable enough for me.

Next thing I tried is to use 38KHz modulated IR LED. The results are much better. However, I need more powerful LEDs to be able to get through the glass surface and able to detect a reflection properly.

It appears that many high-power IR LEDs are not so high power. I tried IR LED from a remote control, that worked nice so I need to be able to get 400 of those without braking a bank.