Field Emission Display (FED)
An FED projects pictures using the same light emitting principle as CRTs. An FED removes electrons from the cathode, and makes them collide with fluorescent material applied to the cathode, thus emitting light. While the cathode of a CRT uses a point electron source, an FED uses a surface electron source.
Six-inch color FED panels have already been manufactured, and research and development on 10-inch FEDs is proceeding very rapidly. When compared with TFT LCDs, FEDs offer a superior viewing angle (160 degrees both vertically and horizontally) and are several microseconds quicker in response speed.
Light emitting principle of an FED system
Digital Micromirror Device (DMD)
A DMD has a structure in which an SRAM chip is covered with aluminum mirrors measuring 16 m square. The two opposite corners of each mirror are supposed by columns, and rotate while keeping a }10 degrees angle from the horizontal. The mirrors control the reflecting volume of light from its source, projecting a picture on the screen.
Because a DMD operates completely under digital control, the picture is not distorted by noise, and a seamless picture can be projected on the screen. (DMD technology is only applicable to projectors)
A DMD projector consists of a DMD of 768 by 576 pixels, a Xe arc lamp, a color filter and a lens. The DMD chip is irradiated with light approximately 2,000 lumens in brightness, and 640 by 480 pixel pictures are projected. Sixty 480-line pictures are projected on a 100-inch screen every 1/60 of a second.
Configuration of a DMD projector
