misc.


DTI announces their autostereoscopic display

From Electronic Engineering Times -- Monday 1991 October 21st
By Richard Doherty

"Rochester, N.Y. - The first commercial display to deliver video and computer-generated images in true stereoscopic 3-D, without the need for special glasses, has been developed by Dimension Technologies Inc.

The introduction of the new color 3-D display comes 16 months after Dimension rolled out a smaller, monochrome flat-panel screen that also provided stereoscopic imagery without the need for special viewers or glasses. The new displays are available now for PC systems; Apple Macintosh and Unix workstation versions will soon follow.

Because of the fast response of the active-matrix LCD, the display works in real time. The LCD measures 12 x 10 x 6 inches and weighs eight pounds. It provides a contrast ratio of 100:1. The viewer looks directly at the display; no overlays of any kind are needed.

The key to the display's operation is a technique developed by Dimension for guiding the light behind the LCD so that one set of columns is illuminated at a time. Each LCD has two sets of vertical columns, each comprising 320 pixels. Therefore, a 640 x 480 display actually consists of two 320 x 480 sets of columns.

The sets of columns alternate on the display. As one set of alternating columns is illuminated - for 1/30th of a second - the left eye sees it. When the column darkens, the left eye retains an after image. Simultaneously, the right eye picks up the other set of columns as it is lit. The brain combines the two continually alternating sets of images to form one image that has the illusion of stereoscopic depth.

Several people can view the display at one time. There are several sets of "sweet spots," where perfect stereoscopic viewing is possible. The ideal viewing distance to achieve stereoscopic perspective is about 30 inches. At that distance, several 2.5 to 3 inch wide viewing regions deliver stereoscopic perspectives. The display can also be set to simultaneously show two-dimensional text and graphics.

Dimension is now developing a special display for NASA's Ames Research Center. Larger resolutions and panel sizes are being explored for use in "telepresence" applications, in which remote, stereoscopic TV camers would deliver real-time 3-D perspective to human operators.

The display provides 4096 colors now, and a 32000 color display is "just around the corner," according to Dimension Engineer Arthur Roberts. The display attaches to any host PC via its VGA port; within a few weeks, a SCSI-port version will be available. That will permit its use with the Apple Macintosh and a slew of workstations and servers equipped with SCSI ports.

[TEXT DELETED CONCRNING ITS POSSIBLE APPLICATIONS...]

Limited quantities of displays are shipping for delivery before the end of the year. Commercial volumes are expected next summer. Unit pricing will be under $10,000."



Synthetic 3D Imaging / Mark Lucente / copyright 1996