Printer Friendly

Putting color into monochrome displays.

A device that uses liquid crystals as a gate to control the passage of light can now convert the yellow glow of a cathoderay tube into various shades of color. This shutter, developer by Tektronix, Inc., of Beaverton, Ore., allows alternating bursts of red and green light (the components of yellow light) to paint brightly colored images over a screen that would normally show only a single color.

The shutter consists of several polarizing filters and a liquid-crystal cell, which form a sandwich that can be placed in front of a cathode-ray tube. Electrical signals sent to the liquid-crystal cell rotate the liquid-crystal molecules so that green and red light get through at different times. If the switching rate is fast enough, the human eye mixes the colors to produce a colored image. A special circuit board coordinates the liquid-crystal activity with output from a computer.

Although this system doesn't provide all the colors offered by a conventional color television, it offers a much sharper picture. Word processing, for example, can't be done very well on a color monitor becuase small letters are too fuzzy. With a liquie-crystal shutter, a monochrome display retains its original clarity while color is available to highlight passages or to label charts.
COPYRIGHT 1985 Science Service, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1985, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:cathode ray tubes
Author:Peterson, Ivars
Publication:Science News
Date:Jul 27, 1985
Words:207
Previous Article:Lighting up magnetic memories.
Next Article:VDT work station standards proposed.
Topics:


Related Articles
The future of computer monitors.
RECYCLE THOSE CRTS.
Data on display: the cathode-ray tube, which dominated display technology for half a century, has given way to flat-panel displays. All current...
LOGGED ON: GETTING INTO THICK OF PCS; COMPANIES STRIVE TO THIN MONITORS.
EPA issues CRT rule.
Marshfield's West keeps nerves in check as he prepares for a spin at state meet.
BASEBALL: CAVS MAP OUT TITLE-GAME PATH CLEVELAND 12, KENNEDY 3.
'BAMAKO' PUTS HUMAN FACE ON AFRICA'S PLIGHT.
HART HIGH BAND PUTTING ON SHOW TO PAY ITS WAY TO CHAMPIONSHIPS.

Terms of use | Copyright © 2016 Farlex, Inc. | Feedback | For webmasters