Subject: How to destroy Sega glasses

From: Dave Stampe-Psy+Eng <dstamp@watserv1>
Date: Sat, 11 Jul 92 00:08:18 -0400

Leave them plugged in for 3 weeks with one lens having DC applied to it.
It gets sort of coagulated, milky and smeared out and NEVER recovers.
Lucky I have spares...  and I'm glad I put the auto switchoff in the
Sega driver code.

- Dave Stampe

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From: Chris Hand <[email-masked]>
Date: 11 Jul 92 21:37 +0100

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> Lucky I have spares...  and I'm glad I put the auto switchoff in the

Well done that man!

On a related topic, I was talking to a colleague whose research involves
various LCD stuff and he said the SEGA glasses can't be switched at a rate
higher than about 50Hz because of limitations of the liquid crystal.  He
said that if you want *fast* switching you have to use a different liquid
crystal (ferro-electric or chromium dioxide or something... :-).

Anyone have any evidence or arguments to the contrary?

Also, has anyone built the alternative SEGA specs interface that
can control the shutters individually (uses a 555 timer) ...?

Chris

-- 
Chris Hand, Lecturer                Internet mail: [email-masked]
Dept of Computing Science,          Voice: +44 533 551551 x8476
De Montfort University, The Gateway,  Fax: +44 533 541891  FIDOnet: 2:440/32.50
LEICESTER, UK   LE1 9BH            >> We *used* to be Leicester Polytechnic! <<

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From: Dave Stampe-Psy+Eng <dstamp@watserv1>
Date: Sat, 11 Jul 92 21:41:59 -0400

You can switch them at any rrate you please, but the turn on/off time is 
about 500 uS, so you'd have to leave blank areas at the top and bottom of the 
screen if you were to use 120 Hz, for example.  My VGA card does 72 Hz, and
they work just fine.  The cells in the Sega are pretty decent for speed:
their main problem is low light transmission (the Sega glasses are NOT
made of dark plastic: they're just designed to hide the darkness of the
cells).  The Stereographics CrystalEyes are very clear, but also bleed
through a bit more, and cost far more.

- Dave Stampe