Neat stuff at the SID Conference
Posted May 24, 2005
The Society for Information Display held their annual conference in Boston this year, so I couldn't resist dropping by to have a look at the exhibits. Some really nice stuff: everything from 100-inch flatscreens to normal-eyesight 3D panels to flexible electronic ink displays to laser-driven heads-up monitors. I'll highlight a few things that I ran across for the first time, even though the old players ( MicroOptical, Kopin, Kent, eInk, MicroVision, etc.) were also present and had their usual ranges of cool stuff.
Kodak was showing off their new flexible displays. They actually licensed the cholesteric-liquid-crystal technology from Kent, and then applied their own knowledge of how to do precision chemical engineering on large films. So you end up with a flexible display that is also passively driven and bistable (i.e. zero power once you set the pixels). They manufacture the stuff on 16-inch continuous rolls with row/column electrodes printed right on them, and you can just cut your desired display panel right out of it and attach drive electronics. Sweet! Demo kits will be available later this summer. The examples they had were relatively low resolution (15 dpi) but they have up to 100 dpi in the works.
Lumus was showing off their heads-up display, which employed some very novel optical technology (which I'm happy for, because while the microdisplay panels have been getting better and better, unobtrusive optics have lagged behind). They use an array of microprisms to direct the light sideways though a total-internal-reflection piece of glass until it reflects off another microprism array into the user's eye. The net result is that the only thing in front of the eye is a transparent piece of apparently flat glass with a see-through display projected in it. Very nice! This is just begging to be integrated into eyeglasses by MicroOptical, since it is a much better approach to the problem than their own relatively thick embedded half-silvered mirror.
Cambridge Flat Projection Displays had a similar sort of product on the macro scale. In this case, they use a wedge-shaped piece of glass with a video projector entering it at one end at an oblique angle. The light bounces back and forth up the wedge by total internal reflection, its angle gradually increasing until it exceeds the critical angle and leaves the glass. The clever bit is that they can control exactly where it leaves the glass by setting the angle it enters at, so they can paint an image that way: think of it as a projection TV where you fold the light path back and forth so you only need a very shallow angle from the screen to do your projection properly. The actual product here is not terribly special, but the general technique I think would come in handy for translucent display panels.