I’m looking for a way to use a IR sensor to detect movement. I’ve seen some examples on the web on how to use a IR sensor, but I’m not sure about it. For instance I’ve seen IR sensors on parking doors and they have a reflector on the other side. None of the examples I’ve seen mentions the use of a reflector and I don’t know which role it really plays.
Can somebody fill me in here?, some link, tutorial, article I might have missed?
Thanks in advance!