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From: frankb@hpsad.HP.COM (Frank Ball)
Newsgroups: sci.electronics
Subject: Re: Laser show controllers?
Message-ID: <1840048@hpsad.HP.COM>
Date: 12 Jun 91 16:56:55 GMT
References: <1991Jun11.202312.10073@kcbbs.gen.nz>
Organization: HP Signal Analysis Division - Rohnert Park, CA
Lines: 16

/ Mike_Diack@kcbbs.gen.nz (Mike Diack) /  1:23 pm  Jun 11, 1991 /
*How about the focus/tracking mechanism out of a CD player ? good 2 axis 
*movement & very fast.
----------
I bought an old laser disc player surplus for $70 (no there aren't any more).
It has a He Ne laser and X-Y deflection mirrors.  The mirrors were controlled
by a complex feedback loop, but that circuitry that is not usable (for anything
but the origional function as a laser disc player).  There were some polorizers,
splitters, and lenses that I ripped out.  The mirrors have voice coils on them
(8 ohms), and I was able to use the origional deflection amplifiers.  I can get
about 200 Hz (it's rolling off by this point) of bandwidth out of the mirrors.
It looks ok with music, more bandwidth would be nicer with some types of music,
it's plenty for other types.  The bandwidth is much to limited for any type
of fancy graphics displays.

Frank Ball   frankb@hpsad.HP.COM   pyramid!hplabs!hpsad!frankb