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by fest 3219 days ago
On a related note- do you know of any books that cover diode laser safety? Specifically, I'm working on a FMCW laser rangefinder (hobby project to teach myself more of analog electronics) and would like to know what is the maximum optical power I should use.
1 comments

There's actually a good quick guide to this in the article: stick to the laser pointer classification of less than 5mw.
I'm more interested in things like: if the diode is on for half the time (50% duty cycle), can I use 10mW? if I transmit a high frequency chirp with even less total duty cycle, can I use even more power?

Not that it really matters in my case: I will probably scrap the project when/if I make a good enough amplifier stage and phase detector for short range where 5mW should be enough.

Well, Hobbs is also the place to go for how to make that amplifier stage. He has some articles online for photodiode front ends, that are quite informative.

Admittedly I've never looked into those issues because the gadgets that I've helped design are all Class 1 -- the system is fully enclosed and interlocked.