From: hlab@milton.u.washington.edu (Human Int. Technology Lab)
Subject: Japanese stereo TV/computer terminals
Date: Tue, 18 Jun 1991 16:10:35 GMT
Organization: University of Washington, Seattle




From BUSINESS WEEK, June 24, 1991:
 
 
	THREE DIMENSIONS, NO FUNNY GLASSES
 
		Watching 3-D movies wasn't always fun.  For years, 
	you had to don glasses with red and green lenses that
	promised crude images and a cross between a popcorn 
	hangover and a migraine.  Lately, companies such as Imax
	Systems Corp. in Toronto have refined this approach with
	liquid-crystal goggles.  But Imax's short films are costly
	to produce, and they've been relegated to science museums
	and exhibitions.
 
		Now, Nippon Telegraph & Telephone Corp. is
	developing 3-D liquid-crystal displays (LCDs) that don't
	require special glasses.  Like earlier systems, NTT's
	prototype simultaneously transmits separate images,
	recorded at slightly different angles, to each eye.  But
	instead of using colors or shutters to keep the sets of
	images discrete, the system employs an outer screen,
	known as a lenticular lens, which fits over a 15-inch
	color LCD panel.  This lens is lined with hundreds of
	vertical ridges that divide and direct the twin images
	to the eyes.
 
		Others have tried lenticular lenses.  But in
	earlier versions, a slight sideways movement could mix
	the signals and shatter the effect.  NTT's display has
	two infrared sensors that track a viewer's head position
	and adjust for these movements.  NTT hopes to produce
	its screens for computer terminals and video phones but
	says commercial systems are still two years away.
 
					(Edited by Robert Buderi)