Motion sensor with second contact to create beam

[Mike_Maxwell]

@fightingmajor

Does anyone know of a motion sensor that works if someone breaks a barrier like the sensor in an elevator. Basically if someone broke the barrier of the motion beam then I would get a notification, but I don’t want the wide spread area that most motion sensors cover. Not sure if I’m doing a great job of explaining this.

I’ve had some success putting tubes of various lengths over the PIR sensor to limit its field of view.
I have several placed across doorways and stairs in my home.
I heat shrink the tube to the PIR with the unit dissembled, and remove the metal tube or not depending on the use case.