Re: IR filters

[quk@isham-research.demon.co.uk (Phil Payne)]

In message <199809172238.SAA03597@urq.East.Sun.COM> Robert Houk - WorkGroup Server Firmware writes:

> How much power really is needed? The source laser *must* be down in the
> milliwatt range, and must be reading microwatt levels reflected back. It

Perhaps not that far down the milliwatt range, though.

It's dangerous to point a laser near an eye, but only because the eye
can focus a coherent beam to a point intense enough to cause retinal
damage.  An IR beam would not be brought to focus in the retinal plane,
though, so the same risk doesn't occur.

It's also probably pulsed, and the pulse might be very short.   Perhaps
it's as high as the low hundreds?

--
 Phil Payne
 Phone: 0385 302803   Fax: 01536 723021
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