Liquid crystal displays have become very popular because of the combination of price, image quality & power efficiency. But LCDs still have a lot of room for improvement, as they only transmit 5-10 percent of the total backlight to the user, and still use quite a lot of power.


The researchers from Microsoft & the University of Washington report in this week's Nature Photonics about this "telescopic pixel" technology.

The telescopic pixel design is based on the optical telescope. Each pixel consists of 2 opposing mirrors where the primary mirror can change shape under an applied voltage. When the pixel is off, the primary & secondary mirrors are parallel & reflect all of the incoming light back into the light source.

Performance tests on arrays of telescopic pixels suggest that these kind of display could be very energy-friendly in the nearby future. Backlight transmission was measured at 36%, and this could reach 56 percent with design improvements, according to simulations.

The Pixel response time was 0.625 ms, which is a lot faster then LCDs can currently handle (2-10 ms). Because of the fast response times the technology would also be fast enough to allow sequential color processing where colors are displayed as rapid pulses of red, green & blue. The intensity of each pixel can be smoothly varied from 0 to one 100% for more realistic color shades & gray scales.

The technology is compatible with current LCD production processes, so it shouldn't be more expensive to manufacture these kind of displays then current LCD panels.

The only drawback of this new technology would be the contrast-ratio. Experimental measurements conducted with non-collimated light showed a very low contrast-ratio of 20:1. Simulations indicate that contrast-ratios of up to 800:1 may be possible, which is also possible with current LCD technology. Plasma & OLED have much higher contrast-ratios, so a lot need to be done to compete with these technologies.