From: Dave Stampe-Psy+Eng <[email-masked]>
Date: Thu, 24 Oct 91 12:31:11 -0400

[email-masked] (Christopher Russell) posts:

>I just kinda had a crazy idea and I was wondering what you more
>experienced types think of it.  (Maybe this is already being done, I
>don't know).  Maybe one small screen could be used with shutter
>glasses in between the screen/optics and your eyes.  I've heard the
>Sega glasses aren't too good, but assuming that good shutter glasses
>were used, it seems to me one could get away with one screen and save
>weight and money.  Though I'm not sure how you could place the screen
>(private eye? lcd? ) without having to use mirrors to get it to both
>eyes. hey, just brainstorming...  This might induce some SERIOUS
>eyestrain.. Whatcha think...

You're right-- the problem IS how to get the display image to both eyes.
Unless you use fiber optics (HAH!) you need mirrors to get both eyes
in the act.  The optical path is so long that you get a FOV of less
than 20 degrees.  If the images are'nt placed properly, you probably
won't be able to fuse the two inages, and the displays will LOOK close
(not good for the VR illusion.  You might try strong prisms to "bend" the
display into place, but this causes BIG distortions with the prism
power you'd need.  Also, each eye will see an image of the display tilted
in opposite directions.

That means that for non-stereo eyephones, you have the choice of:
1) using 2 displays, and feeding them both with the same signal
2) using one display, and covering/closing the other eye

BTW, is anyone SERIOUSLY planning to drive their eyephones with
stereo pictures, or is eyeryone going to start with a single image
(flat).  I'd like to suggest emulating the Sega glasses as a start for
eyephone stereo.

Switching the LCD backlights on and off won't work, as the image on the 
panels changes too slowly and the backights switch too slowly 
(I've measured their rise and fall times).  A better way is to switch
the video (but NOT the sync signals) to each display on and off.
This will have lower the contrast somewhat, of course.  If you're using
CRTs or camera viewfinders are used, blanking signals could be sent right
to the CRT driver electronics.

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| My life is Hardware,                    |                              | 
| my destiny is Software,                 |         Dave Stampe          |
| my CPU is Wetware...                    |                              | 
| Anybody got a SDB I can borrow?         | [email-masked] |
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