I have a closed box with a hole in the wall. A IR beam is directed at the front of the box. Due to a small 6mm borehole in the wall only a certain part of the beam can pass trough.
The left small pieces are IR sensors. I'm wondering now if I need an additional tube for focusing the beam like depicted?
Application is a light barrier and therfore the beam needs to be not wide but very narrow. 2nd question is: is there a difference if the ir sensor is placed like the right one or like on the left position?