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New “telescopic pixel” displays to replace LCD/Plasma

Liquid crystal displays (LCD) and plasma technologies are the most popular of the display/ television technologies currently used in desktop and mobile computing since LCDs are thin, have high resolution, are low cost, and offer low power consumption and long lifetime. But the negative side of LCD systems is that they do not have high contrast and they only transmit 5 to 10 percent of the total backlight to the user, accounting for up to 30 percent of the total power consumption of a laptop.

In this week’s Nature Photonics, researchers from Microsoft and the University of Washington report a new display technology called “telescopic pixel” that transmits 36 percent of backlight radiation.

Pixel response time, another very important benchmark in displays, is also improved. While LCDs typically range in the 2-10 ms spectrum, Telescopic Pixel technology has already achieved times as fast as 0.625 ms. These response times may also be fast enough to allow sequential color processing where colors are displayed as rapid pulses of red, blue, and green from each pixel, streamlining fabrication and device design. Also, the intensity of each pixel can be smoothly varied from zero to one hundred percent for more realistic gray scales and color shades.

To elucidate, the researchers explain the whole process as follows:

“Each pixel consists of two opposing mirrors where the primary mirror can change shape under an applied voltage. When the pixel is off, the primary and secondary mirrors are parallel and reflect all of the incoming light back into the light source. When the pixel is on, the primary mirror deforms into a parabolic shape that focuses light onto the secondary mirror. The secondary mirror then reflects the light through a hole in the primary mirror and onto the display screen.

Each pixel is produced in two halves by standard photolithography and etch techniques. The secondary mirror is simply a lithographically patterned array of aluminum islands on glass, but making the primary mirror is a bit more complicated. First, an indium tin oxide (ITO) electrode is deposited on a glass substrate and coated with polyimide. The polyimide acts as a support and electrical insulator for the primary mirror. Aluminum is then sputtered onto the polyimide and photolithography is used to pattern 20