I have used tiny focusing lenses for optoelectronic sensors in the past to
narrow the width of an LED beam down to about 1mm in dia at a distance of
10mm but no less....The application was to track the edge of a notch on a
tray on a conveyor belt and the actual diameter of the beam on the target
was not very critical.
It does seem feasible to get the beam to a pretty tight circle
though...Edmund Scientific has loads of lenses one could browse through.
Keyence Sensors has some lens accessories for their optoelectronic sensors.
Sounds like an interesting project.
Madhu
----- Original Message -----
>  I guess what I'm interested in finding out is if anyone has had any
practical >experience of focussing an LED's beam to close tolerances.
Maybe then I'll give this >a go!
> Regards,
> Mark Brown

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