Newsgroups: sci.virtual-worlds
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!van-bc!ubc-cs!uw-beaver!milton!hlab
From: prosun!te (Thilo Ernst)
Subject: Poor man's VR  (world's cheapest stereographic display)
Message-ID: <1991May17.213646.27113@milton.u.washington.edu>
Sender: hlab@milton.u.washington.edu (Human Int. Technology Lab)
Organization: University of Washington
Date: Fri, 17 May 91 13:42:18 +0200
Approved: cyberoid@milton.u.washington.edu




Hi Virtual Realists,

Here's my version of a REALLY cheap stereo display device, which
I invented some years ago visualizing and animating some wireframes
on a hercules-equipped XT (top view): 

_______________________________________
|       _______          'table' plane |
|      /  PC   \                       |
|     / monitor \                      |
|    |_LI_____RI_|                     |
|       \     .|                       |
|        \ [ . |                       |
|         \[.  |                       |
|         /[   |                       |
|        / [   |                       |
|       /      |                       |
|      .___^___.                       |
|     /YOUR HEAD\                      |
|     |(somewhat|                      |
|     \stylized)/                      |
|       --------                       |
|______________________________________|

Simply place a mirror ([)  between you and your PC/workstation
screen and make your software display the left and right stereo 
images LI and RI side by side, with one of them (LI) mirrored (by
software, too). Surprise: LI's virtual image exactly matches RI, 
as shown above.Full 3D look-and-feel (almost) free of charge, 
although not really well suited for headmounting :-)
A more convenient variant is to use special 'glasses' containing
prisms or (small) mirrors to make the eyes look onto different 
images displayed side by side (no need for mirroring of one image).
Works very fine, but yields headaches if wrong adjusted. 
I found this solution sufficient for experiments; might be useful
for off line prototyping in a system like Pausch's 5$/day VR, too.

COPYLEFTed, i.e. donated to the non-commercial, non-military 
public domain hereby, unless this is a (g)oldie (sorry then).

Have a pleasant journey into 3space,

  Thilo Ernst, Berlin, Germany

(te@gmdtub.uucp, te@prosun.first.gmd.dbp.de, ..!unido!gmdtub!te)