



Stereoscopic Technologies Currently 
Available for Computer Displays

By John Williamson



	Three of the technologies, stereopairs (either side-by-side or over-under), anaglyph and Pulfrich require only simple glasses which are widely available.  There are several software packages available for each of these three formats of stereoscopic displays.  These include both flight simulators, fractals and computer aided design (CAD) programs.   In addition, because these techniques require only small modifications to existing 3D modeling algorithms, it is possible to write your own programs.
	The following are companies which are currently producing stereoscopic computer displays.  These technologies require hardware modifications to existing computer displays, or proprietary monitors and graphics cards.  As a result, they are considerably more expensive, though the quality of the stereoscopic image is significantly better.  I have also reviewed products from several other companies who have produced stereoscopic computer displays based on alternative designs.  However, these products were either conceptual demonstrations which were never produced or working models which were never marketed.  As a result, I have omitted them from this review.

Review: An interesting idea, very durable, as no glasses are required, it could be used for 'walk-in' audiences.  The quality of the image doesn't approach those of the other systems.  Full color images can be displayed.
Options: None


Product Name: Omni View
Company Address:        Texas Instruments Incorporated
			P.O. Box 655474
			Dallas, TX  75265
Phone: (512) 995-0604
Price: Not commercially available
System: Sun workstations
Technology:  Described as "a real-time auto-stereoscopic, multiplanar 3-D display system", the 3D image is drawn by lasers on a disk spinning at 600 rpm.  Current resolution is 750X750 pixels.  
Review: Aside from the fact that viewers do not have to wear glasses, the most significant aspect of this design is that it displays a three dimensional image on a three dimensional surface.  As a result, the viewers can actually walk around the image, look down or up at the image.  The display is crisp, though currently only line drawings can be displayed. 


Product Name:SpaceGraph
Company Address:        BBN Systems and Technologies Corporation
			BN Laboratories Division
			10 Moulton Street
			Cambridge, MA  02238
Phone: (617) 873-3000
Price: $35,000
System: PC 386 or better
Technology: An autostereoscopic varifocal mirror, multiplanar display system.  A forerunner to the Omniview system, the images are displayed on an ocilating mirror.
Review:  No glasses are required, the images are sharp, though color is limited to green.


Product Name: DTI 100 M, DIT 100 C
Company Address:        Dimension Technologies, Inc.
			176 Anderson Ave.
			Rochester, NY  14607
Phone: (716) 458-1130
Price: $6,700 for monochrome,  $22,000 for color system
System: PC AT, Mac, UNIX 
Technology: An autostereoscopic liquid crystal monitor system.  No special glasses are required.  
Review: Have not seen this model in person.  A similiar system I reviewed several years ago gave a blurry, ghosty image.  Probably the smallest of all displays.


Product Name: SGS series of Stereoscopic Display Monitors
Company Address:        Tektronix, Inc.
			Liquid Crystal Products Marketing
			P.O. Box 500 M.S. 48-300
			Beaverton, Oregon  97077
Phone: (503) 627-5000
Price: $9,000
System: PC AT, Macintosh, Unix
Technology: Multitime-multiplex technique alternately displays the left and right-eye images on a special monitor.  The card and monitor allow a very fast refresh rate, which eliminates all flicker.  Uses passive, polarized glasses.  Two sheets of liquid crystal are attached to the monitor and alternately display each image.  Several systems/screen sizes are available.
Review: A very clean, sharp image.  Easy to modify your own code to produce stereoscopic images.

		
Product Name: 3Display
Company Address:        Stereographics Corporation
			2171-H E. Francisco Blvd.
			San Rafeal, CA  94901
Phone: (415) 459-4500
Price: $9,000
System: PC AT, Macintosh, Unix
Technology:  Multitime-multiplex technique alternately displays the left and right-eye images on a special monitor.  The card and monitor allow a very fast refresh rate, which eliminates all flicker.  Uses active, liquid crystal glasses, which are kept in sync via an infra-red link.  Several systems/screen sizes are available.
Review: A very clean, sharp image.  Easy to modify your own code to produce stereoscopic images.  The glasses are remarkably lightweight and durable.

Product Name: Virtual Reality
Company Address:        VPL Research Inc.
			656- Bair Island Road, Suite 304
			Redwood City, CA  94063 
Phone: (415) 361-1710
Price: $250,000
System: Silicon Graphics
Technology:  Essentially stereopairs, with two computers and two modified 2" monitors, which are placed directly in front of the eyes via a pair of "eyephones."  Each computer is responsible for the images presented to only one eye.  The stereoscopic technology is not the main selling point of this technology, rather the sense of immersion in a "virtual world."  Because the computer keep track of not only head position, but hand gestures and locations as well, a user has the impression that they are actually inside the computer generated world.  Currently, the images do not compare with the clarity and resolution of other less expensive technologies, though this gap will shrink very rapidly.

Other Companies /Organizations of Interest

Reel 3-D Enterprises, Inc.
P.O. Box 2368
Culver City, CA  90231
Phone: (213) 558-1653 for orders only
As the "world's largest mail order selection of new 3-D supplies",  Reel 3-D carries a wide selection of anaglyph glasses and handheld stereoscopes and 3-D print viewers.  These can be used on any graphics system, by either drawing anaglyph or side-by-side pairs.  The also carry several books on 3D techniques and history, though nothing devoted exclusively to computer generated 3D images.


3-D TV Corporation
Box 13059 
San Rafeal, CA  94913-3059
Phone (415) 479-3516
The only source for 3D movies which you can watch at home.  These will run on your TV and VCR using liquid crystal shutters and the Multitime-multiplex technique.  Prices start at $190 for a complete system and one movie.


National Stereoscopic Association
P.O. Box 14801
Columbus, OH  43214
A non-profit organization devoted to the advancement new 3D technologies and the preservation of  antique 3D images.  Current membership exceeds 3,000.  Membership includes a subscription to Stereoworld, a bimonthly publication complete with 3D illustrations.  Articles cover both the history and recent advancements in 3D technology.  If you are interested in 3D, this is one organization you should join.


SIGGRAPH: Association For Computing Machinery: Special Interest Group for Computer Graphics
11 West 42nd Street
New York, NY  10036
SIGGRAPH is a large special interest group in ACM.  Their annual conferences include demonstrations by some of the above mentioned companies as well as panel discussions and courses on stereoscopic computer graphics.
