Hi all, new here. I have a question hopefully some of you can help with. I am working on a project that requires 3 break beam sensors in a row. Initially i had decided to use lasers and sensors on one side with mirrors reflecting them back to the sensor. After some thought this may be difficult to align. so now I am looking for better suggestions that wont break the bank. Something like a garage door sensor with the reflector on one side. this is going to be used outside and i need a range of 1-2M. Thank you all in advance for your suggestions.
here is a thing worth knowing: IR LEDs that can not be seen by the naked eye look like spotlights on a CCD camera. The CMOS camera in your cellphone will not see them, but a decent CCTV or digital camera will see them.
point a remote control at a camera to determine if it can see IR. I would use my $5 swap meet snapshot camera, not the Canon EOS.
so, you can do your alignment visually without looking directly at a laser
i get that and thank you for your response, what i mean by hard to align is i will be shooting the laser 1-2M hitting a mirror, then i need to align the mirror to hit the sensor next to the origin point again 1-2M away. I just think trying to hit an aprox 3mm target at that distance will be a pain. The garage doors use those reflectors that only require a general alignment and have a lot of leeway.
also, it should be noted that the 3 beams are only 10 inches apart. so care has to be taken that one does not interfere with the other
Why do you want to use reflectors over such a moderate distance? my garage door opener has an emitter on one side and a sensor/detector on the other side (some twenty+ feet away. It would be much easier to isolate individual sensors spaced at such a short distance on the recvr side and alignment becomes almost a null issue.
envme123:
also, it should be noted that the 3 beams are only 10 inches apart. so care has to be taken that one does not interfere with the other
That is avoided by modulating each beam with a different code and programming the sensor code to look for it's code, only.
Paul
i want to use reflectors because i will not have the ability to run wires across the span as you can on a garage door
Use retroreflectors and they only reflect back to where the light came from. As long as the IR beam hits the reflector you'll be getting a reflection back.
wvmarle:
Use retroreflectors and they only reflect back to where the light came from. As long as the IR beam hits the reflector you'll be getting a reflection back.
+1
Also known as corner cube reflectors.