Super-Thin Computer Screens Near Reality For Use In Tight Spaces

September 10, 1997

GAINESVILLE — Hospital rooms, surgery suites, fighter plane cockpits and tanks — high-priced real estate where space is at a premium. They also are perfect places for super-thin color computer monitors that will result from technology being developed at the University of Florida.

Researchers are working to provide color for computer screens so small they can be mounted on the head or helmet and still display brilliant, accurate colors comparable to a color television picture.

“Now that we have computer-assisted surgery and smart weapons, the last thing surgeons and fighter pilots need is a big computer monitor crowding their valuable and small work space,” said Paul Holloway, professor of material science engineering at UF, a member university of the Phosphor Technology Center of Excellence.

Here, experiments are under way to improve the efficiency of thin films of phosphor that emit light and color when struck by electrons. These phosphor films will be used in a new breed of thin color monitors.

What makes today’s computer color monitors so long and deep is the cathode ray tube inside. The electron gun at the back of the cathode ray tube needs length to bombard the inside of the TV screen with electrons, said Holloway.

The new, slim color monitors instead will use Field Emission Display (FED) technology. FED monitors, equipped with hundreds of miniature electron guns firing a short distance instead of the single large electron gun firing a long distance, will spray electrons to create images. Phosphor films will react to the electrons to create color. But brilliant, lasting colors will be a reality only after researchers perfect efficient, long-lived, thin phosphor films.

True, today’s laptop computers have thin screens, but they use liquid crystals that are either monochrome or, at best, render poor quality lighted colors and have other drawbacks, said Holloway.

“You can’t see liquid crystal screens from a large angle. Also, the liquid crystals that provide the visual image are not rugged enough to stand up to vibrations such as those that rattle a tank,” said Holloway. “Neither limitation is good for monitors used in combat or surgery.”

Holloway said making dependable, thin FED monitors with good color display is vitally important to medicine and defense.

“Soon, instead of looking up at a computer screen when doing endoscopic procedures, surgeons will be able to wear a helmet with a small, thin, FED screen just in front of their eyes,” he said. “Of course, in surgery it is important to be able to see tissue colors accurately and right in front of you. FEDs with good color will make that possible. Likewise, soldiers driving tanks will wear goggles that will have a display feature. But the visual display must work at 20 degrees below zero in Siberia or 120 degrees above in Saudi Arabia. Liquid crystals are too temperature sensitive.”

Head- and helmet-mounted displays have been around awhile, Holloway said, but current versions are cumbersome and heavy. FED technology promises to make monitors wafer-thin compared with today’s. Once the phosphors for FEDs are perfected, they will be useful in virtual reality systems as well as in the “real time” world of the cockpit or surgery suite. Holloway said the UF researchers want to get the best colors possible from the thin phosphors while expending the least amount of electron energy.

“We can make the phosphors work for 1,000 hours, but we’re shooting for 10,000 hours,” said graduate student Sean Jones, who is working to improve the efficiency of thin film phosphors. “Also, the color quality standard set by your color TV is what we’re working toward.”