Regarding the message from Guy Cox:
 
> >Our MRC 600 opens the laser shutter spontaneously when, or shortly
> >after, the scan head is turned on.  Sometimes it will do this again
> >if the scanning is stopped (though the software).  This only happens
> >in the first 5 minutes after switch-on - after that everything is fine.
> >It's a trivial matter - *except* that if someone happened to do the
> >wrong thing with the sliders on the microscope they could get a
> >proportion of the laser beam coming out of the eyepieces, and this
> >worries our safety officer.
 
Laser light is coherent, i.e. parallel and in phase. However, that is
longer the case (it is no longer parallel) after it passes through a
projector lens, such as an ocular.
This isn't to say that it might not be uncomfortably bright, but is
shouldn't be dangerous in the manner of a laser. Comments appreciated,
since I've never fully understood this particular paranoia.
 
Susan Kaminskyj
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