Carl,
Do you think these displays would have any effect on the future of graphics memory requirements?
eetimes.com
Philips to use tiling technique for large, flat displays
By David Lieberman
EE Times
(11/11/99, 5:34 p.m. EDT)
SAN JOSE, Calif. ? Philips Flat Display Systems is betting on a seamless tiling display technology that it says will deliver unprecedented price/performance for 36-inch and larger flat-panel displays within just a few years.
An increasingly potent player in flat-panel displays, Philips FDS has put "a substantial joint-development team in place" to create products based on the tiling technology of Rainbow Displays Inc. (Endicott, N.Y.), said Hafiz Haq, vice president for business development and strategic planning at Philips FDS, based here. The company has also taken a minority equity stake in privately held Rainbow.
If the joint project bears fruit, those shopping for a big TV in 2001 may have a new technology choice along with CRTs, rear-projection sets and plasma displays.
Tiling, said Steve Sedaker, vice president of sales and marketing at Rainbow, "is a breakthrough and enabling display technology that combines several smaller-size displays to produce a single, large flat display without any visible seams." In Rainbow's case, the tiles consist of active-matrix (AM) liquid-crystal display panels.
The Rainbow techniques go beyond "mechanical tricks" to hide the physical seams and "play electronic and optical tricks as well," said Haiji Yuan, director of business development at Philips FDS and project manager for the tiling effort. The seams of a 38.6-inch display constructed by Rainbow from a 2 x 2 matrix of 19.3-inch panels are completely invisible, he said, "whether you're five feet away or two inches away."
Rainbow was founded in 1996 by a group of executives from a former Endicott IBM packaging group and a pair of Cornell University professors. All told, 26 patents covering packaging, electronics and optics involved in the company's tiling technology have been filed, said Tom Ruane, Rainbow chief operating officer, who declined to discuss many specifics.
Ruane did note, however, that the dot pitch across LCD boundaries is the same as the dot pitch within the LCDs. The Rainbow technology is implemented into a "stack," comprising the LCDs, a custom light box and "optical and illumination treatments," said Ruane. The package is very physically robust and provides excellent images with a wide viewing angle, said Philips' Yuan.
Time saver
The appeal of tiling LCDs, according to Philips, is that it breaks free of the size-increase curve for individual LCDs while taking advantage of the impressive price/performance curve for those same displays. "The typical growth rate in diagonal size [for AM LCDs] for the last five to 10 years is a little less than one and one-half inches per year," said Yuan. "At that rate, with the biggest LCDs now currently at 22 inches, it would take about 10 years to get to 36 inches or larger. Tiling will give us a 2x or 3x breakthrough over what a normal LCD fab line can handle and we'll get to market faster."
According to Haq, "If you look at things from 30,000 feet, you find a number of new technologies competing for the large-screen space, but none of them have yet proven themselves in terms of cost, performance and reliability. The game is not finished."
Plasma displays are "a major competitor," Haq granted, and one which Philips incorporates into its TVs today.
But, said Yuan, "It's pretty obvious LCDs can offer much better contrast in high-ambient viewing environments. Plasma displays can have washout problems [in bright light] because they're using phosphor to generate light."
As for rear-projection displays, "That's a very exciting field," said Haq, "but as far as maturity, it's well behind tiled LCDs in the optics to get good screen quality."
Tiling, he said, will allow Philips to "piggyback on the tremendous performance improvements and cost reductions which have been achieved by AM LCDs," without suffering the cost increases incurred as LCDs scale up in size. A hypothetical 30-inch AM LCD would probably have about a $4,000 to $5,000 price tag, Haq said, while today's 15-inchers go for about $600, with a probable drop to $400 within a few years.
Do the math
Thus, a 2 x 2 matrix of 15 inchers, tiled to obtain a 30-inch display with a total display cost of $1,600 or under, presents "a tremendous price benefit," he said.
Also, said Haq, Rainbow's 38.6-inch display has SVGA resolution, and its 1/4-VGA LCD tiles are less expensive to manufacture than the higher-resolution LCDs used in conventional applications.
Though Philips talks a good game, the Rainbow display has not been publicly shown. David Mentley, senior vice president at Stanford Resources (San Jose), however, suggested that a successful tiling technology could find a place, given the size limitations of individual LCDs and the efficiency limitations of plasma.
"Tiling makes use of the lower-cost, higher-volume display sizes," he said. "Many approaches have been made over the past 20 years and none has been practical technically or economically yet."
Chuck McLaughlin, principal at the McLaughlin Consulting Group (Menlo Park, Calif.), was more skeptical. "After working on tiled displays at Taliq in the '80s and Magnascreen in the '90s, I am not bullish with regard to either the performance or costs for tiled high-resolution displays," he said. A 2 x 2 array may be commercially feasible, but larger arrays are extremely challenging, requiring a near miracle in design to make them 'seamless.' Many tricks have been tried, including front lenses to hide seams, welding panels together, and others. Everything to date has been claimed [to be] 'seamless,' but really was not. They may have looked pretty good when observed at 90 degrees, but not off angle."
Yet, Philips remains enthusiastic and pointed to market research that projects the large-screen display market to grow from $250 million in 1999 to $5 billion by the year 2005.
The Philips/Rainbow displays will target digital TVs, public information and entertainment displays, financial trading rooms, conference rooms, electronic signs and kiosks. Philips hopes to have small quantities available by late 2000. |
