Europeans ready display contender

Electronic News, August 5, 1996 by Jim DeTar

Edinburgh, Scotland--A technology co-designed by the University of Edinburgh, in conjunction with Thorn EMI and GEC Marconi, is poised to take on Texas Instruments' digital light processing (DLP) chip, used in that company's popular digital projection systems.

The Edinburgh researchers claim the resolution of their ferroelectric liquid crystal (FLC) spatial light modulator (SLM) chips is now approaching VGA quality and revealed they expect to have a 1,024x768 pixel resolution device in silicon within a couple of months.

The European SLM chip uses a technology that is claimed by Edinburgh researcher Ian Underwood to be cheaper to manufacture than the TI device. The European group uses a liquid crystal display (LCD) combined with either SRAM or DRAM memory and what they termed a stationary "mirror" layer on top of the standard CMOS memory/LCD chip to achieve three-color separation.

The mirror is stationary and reflects the light, Dr. Underwood said. "We paint a pattern at about 10 kilohertz. Today we can have 176x176 pixels and we have in development up to 1,024 pixels x 768 pixels, which is at the silicon stage. We expect to see it within the next few months."

Dr. Underwood also outlined technology plans for the ferroelectric liquid crystal SLMs, saying: "Our current plans include the deployment of multiple overlapping metal layers above the circuitry to prevent stray light from reaching the substrate." This prevention is necessary for any application involving high intensity light.

Additional planned technical enhancements include "the use of microfabrication techniques to deposit spacer and alignment layers for the liquid crystal; the deposition of exotic metals for the top mirror layer; through wafer contacts to allow mirrors to be placed on the rear of the wafer; and deposition of transparent conducting layers for transmission mode operation."

Potential applications include head-set projectors and what Dr. Underwood said would be a "Coke can-sized projector" that would be able to project full-sized images onto a screen or wall, and it is claimed would sell for considerably less than what is available today from companies such as TI.

Initially unveiled a couple of years ago, TI's DMD technology and related subsystems are expected by some analysts to yield the company up to $1 billion in sales by 1997-98, according to projections by analysts. TI last year began announcing OEM agreements for its technology with the likes of Proxima Corp. of San Diego and In Focus Systems of Wilsonville, Ore. (EN, April 1995), and continued to do so this year.