Now, mirror-based pixel designs to outdo LCD screens

Washington, July 27 : Microsoft's new telescopic displays, boasting pixels that use a pair of mirrors to block or transmit light, may give the developers of the much in vogue liquid crystal displays or LCDs a run for their money.

The telescopic pixels could lead to displays that are faster, brighter, and more power efficient than liquid crystal displays (LCDs).

In fact, researchers at Microsoft Research have claimed that their design is also simpler and easier to fabricate, which should make it cheaper than the LCDs that rule the markets for TVs, cell phones, and flat-panel computer monitors.

"There is nothing in LCD technology that stands out. The only reason it has done well is it's the lowest price [flat-panel] display today," The Technology Review quoted Sriram Peruvemba, vice president of marketing at electronic-paper pioneer E Ink, based in Cambridge, MA, as saying. Michael Sinclair at Microsoft Research said that the new telescopic pixels switch completely off and on within 1.5 milliseconds and that the ultrafast response time translates to simpler, low-cost color displays.

In LCDs, a pixel is made of three subpixels--red, green, and blue and each subpixel is controlled with a separate transistor circuit, making the circuits complex.

Sinclair said that as the telescopic display switches so rapidly, it is possible to put red, green, and blue light-emitting diodes behind each pixel, and have them sequentially light up to create a color shade.

"This would reduce the complexity and cost of today's LCD," he said.

In fact, the telescopic pixels are also quite brighter unlike in an LCD, where by the time light passes through the polarizing films, the liquid-crystal layer, and the color filters, only 5 to 10 percent of it comes out. The telescopic pixels, on the other hand, let about 36 percent of the light through.

"I could get by with a less-powerful backlight, because the telescopic pixel is more efficient," said Sinclair and added that the greater brightness would also make the display more visible in bright sunlight. The new pixel design by Microsoft researchers uses two micromirrors, one with an aperture and the other placed directly in front of the aperture. In the "on" state, the first mirror bends, sending light bouncing off the second mirror and out the pixel.

The researchers designed the pixels in a layered fashion similar to that of silicon chip fabrication. He said that the telescopic pixel design is simpler than the design of an LCD, with fewer layers, so the fabrication would require fewer steps.

Peruvemba said that the new pixel technology has advantages over current LCDs, but the mechanical parts might compromise robustness.

"There are literally hundreds of thousands to millions of little shutterlike devices that have a mechanical movement. In most devices, what fails first are the mechanical parts," he said.

Sinclair said that Microsoft Research is targeting large, low-cost computer screens. This may prove to be an IT worker's dream, wherein instead of having a small desktop monitor on which you have to switch between windows, a techie could have a "whiteboard-sized thin screen" to work on. The novel pixel design was published in Nature Photonics.

ANI