Xref: utzoo sci.med:4156 sci.electronics:2179
Path: utzoo!utgpu!water!watmath!watdcsu!bmaraldo
From: bmaraldo@watdcsu.waterloo.edu (Commander Brett Maraldo)
Newsgroups: sci.med,sci.electronics
Subject: Re: is low power laser light dangerous?
Message-ID: <4428@watdcsu.waterloo.edu>
Date: 18 Feb 88 17:35:54 GMT
References: <602@anasaz.UUCP> <982@ssc-bee.ssc-vax.UUCP> <670@morningdew.BBN.COM>
Reply-To: bmaraldo@watdcsu.waterloo.edu (Commander Brett Maraldo)
Organization: Unit 36 Research
Lines: 35

In article <670@morningdew.BBN.COM> eli@BBN.COM (Steve Elias) writes:
>	i'm sure someone will correct me if i'm out of date, but...
>
>	the last i heard (Science magazine a few years back), there
>	has been no documented case of permanent vision damage from direct
>	exposure to low power lasers.  

    I have worked with, and been exposed to, the light from both 1mW and
    5mW HeNe lasers.  Due to my carelessness I have had the light from
    these devices enter my eye, unobstructed.  

    I did not sustain any damage that caused a long lasting change in my
    eye-sight.  As for pin-holes in my retinas, I can't comment as I
    haven't had my eyes checked since.  I urge anyone working with lasers
    of any sort - use EXTREME caution, treat the beam as a death ray and
    avoid ANY kind of contact with it.

    Just for fun, here are some numbers:  A comparison between the photon
    outputs of a 1mW HeNe and a broadband thermal source.

    For the HeNe:  10^16 photons/s into an angle of 2E-6 sr.
    For thermal :  10^9  photons/s into an angle of 2*pi sr
		   (note: that's only 320 photons/s into the same solid
		   angle as the laser!).

    BE REALLY CAREFUL!!!!!!

					Brett L Maraldo


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