From: jmelzer@aol.com (JMELZER)
Subject: Re: TECH: LCD yields, configurations, cost
Date: 30 Nov 1995 03:38:56 -0500
Organization: America Online, Inc. (1-800-827-6364)


From: jmelzer@aol.com (JMELZER)

>From: wilson@cs.utexas.edu (Paul Wilson)
>In article <48kvq4$j1f@news1.halcyon.com>,
>Leo Nikora  <Leo_Nikora@vio.com> wrote:
>> [...]
>>wilson@cs.utexas.edu (Paul Wilson) wrote:
>>
>>>...
>>>I would expect that somebody would make HMD's with four LCD's, two per
>>>eye, with only partial overlap.
>>>...
>>
>>Partial overlap has two major problems.  First, with the possible
>>exception of an SGI Reality Engine, there aren't many sources (games,
>>TV, etc.) that generate partially overlapped images.  This might be
>>solved in the future, but there's always the chicken-and-egg quandary.

We build a partially overlapped HMD display that tiles the images. There
are two tiles per eye. The central two are overlapped for a 100 by 30
degree FOV. The input is SVGA video (800 by 600, I think). The electronics
splits the single video channel to the eyes. No muss, no fuss. 

>>Second, the area of overlap always appears brigher than the rest of
>>the image.  This might be solved by complex brightness controls, but
>>that keeps driving costs up.

The overlapped pair appearing brighter is an old wives tale (or shall I
say old husbands tale?) The central pair do not appear brighter than the
flanking pair.

Regards,

Jim Melzer
Kaiser Electro-Optics