I want to use a garage style beam to detect if someone walks in an area. This idea is just like a garage door IR beam from point to point. This cannot be cameras or motion sensors other methods, it must be point to point for a very tight precise detection and easy concealment. I have other thermal and IR devices to detect motion and presence which don’t apply here. This is point to point and the goal is to make it as inconspicuous as possible. The distance is 50’ to watch. I bought several types that have more than enough range but these devices are very large and would require some effort to conceal including having to cover with IR plastic. The other goal is very long life without maintenance or repairs. Once I experimented with a cheap laser pointer and an opto device and could run the light through a 1/4” hole and it was perfect but the laser pointer didn’t last long and it didnt have the range. Any ideas on a small method to do this?