Apple claims that its iPhone 4 "retina display" has pixels so small the human eye can't distinguish one from the other. Researchers at the University of Michigan say they can beat that pixel density by an order of magnitude – and make screens that are simpler to make and more efficient to illuminate too.
The technology – called plasmonic nanophotonics – works a little like the rainbow, if light were refracted through nano-thin metal grates instead of raindrops. Vary the spacing between the grates, and white light appears in different colors. Instead of the multiple layers of glass, metal polarizers, and filter sheets in a conventional LCD, the polarizer is the color filter. The whole color component of the screen is a three-layer all-metal dielectric stack.
The energy savings are potentially tremendous. According to Michigan engineering professor expert Jay Guo, only about 5 percent of the backlight in an LCD screen actually reaches our eyes. This means we could use the technology in optical chip-to-chip communications, or even fiberoptics without the fiber. It could also be used to make high-efficiency, high-resolution projectors, or flexible color screens.
And yes – it does allow for the production of extremely tiny color pixels, less than 10 microns. That U of M logo in the first image above? It's about 12 x 9 microns, or 1/6 the width of a human hair.