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From: esmith@goofy.apple.com (Eric Smith)
Newsgroups: sci.electronics
Subject: Re: Big Screen Projector from tiny LCD TV ?
Message-ID: <ESMITH.90Aug18135130@goofy.apple.com>
Date: 18 Aug 90 20:51:30 GMT
References: <29520@unix.cis.pitt.edu>
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Organization: Frobozz Magic Widget Company
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In-reply-to: fmgst@unix.cis.pitt.edu's message of 18 Aug 90 00:55:20 GMT

In article <29520@unix.cis.pitt.edu> fmgst@unix.cis.pitt.edu (Filip Gieszczykiewicz) writes:

>   <The problem you are going to have to beat is how to get rid of the heat
>   <from your projection source. Any light bright enough to make a decent
>   <projection display is going to throw off a lot of heat. You will have to 
>   <block or remove the IR from hitting the LCD display or it will quit
>   <working. They don't like temperature extremes.
...
>	   Greetings. I recently made curing unit for a dentist. It
>	   uses 4 300Watt halogen lamps and 4 IR filters. The lamps
>	   were $20 each and the filters $40.
>
>	   The filter looks like ordinary thick, bluish-tint glass that
>	   just _loves_ to shatter :-( 
>
>	   Heat should not be the problem. (I can get a 200Watt 12V lamp)

Heating the glass isn't the problem.  The problem is the liquid crystal
BETWEEN the two layers of glass.  They generally don't work well at
high (or low) temperatures.
--
Eric L. Smith      Opinions expressed herein do not necessarily reflect those
esmith@apple.com   of my employer, friends, family, computer, or even me!  :-)