Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site dartvax.UUCP
Path: utzoo!linus!vaxine!wjh12!genrad!decvax!dartvax!robertm
From: robertm@dartvax.UUCP (Robert P. Munafo)
Newsgroups: net.micro
Subject: Re: 3-d spreadsheet
Message-ID: <1697@dartvax.UUCP>
Date: Sun, 27-May-84 02:52:48 EDT
Article-I.D.: dartvax.1697
Posted: Sun May 27 02:52:48 1984
Date-Received: Wed, 30-May-84 00:10:43 EDT
Organization: Dartmouth College
Lines: 20

-
       I have heard of two ways of producing 3-d color TV without
glasses.  The first creates a "virtual image" of a CRT with mirrors
or lenses, which vibrate to make the image move in the 3rd dimension.
This creates an fake image the same way concave mirrors do (you might
remember it from high-school physics) - the three-d effect is not very
good unless you're "used" to seeing three-d this way.
       The other method is to make the glass front surface of the
CRT with many narrow, vertical ridges - like long, thin prisms running
up and down the front of the screen.  For each ridge there should be
several (four to eight will do) columns of pixels displayed on the
screen.  The ridges make each of the eight columns of pixels visible from
only one angle.  Typically, your left eye will see only the first
column of each group of eight and your right eye will see the fourth.
The left-eye image is made different from the right-eye image by the
computer, and you have three-d.   Some of you might have seen three-d
postcards or pictures with this type of surface sold as novelties.
-- 
  
  Robert P. Munafo   ...!{decvax,cornell,linus}!dartvax!robertm