Holographic Video Projection
A holographic pattern representing each frame of the video image is formed on an LCOS chip, and a laser beam is directed toward the pattern. The light interferes with itself through the process of diffraction, resulting in a large, high-quality projected image. Full-color images are generated by directing red, green, and blue laser beams sequentially to the LCOS chip, which forms the image for each color in turn, much like a single-chip DLP projector uses sequential filters on a color wheel. Amazingly, no lenses are required; the image is in focus at virtually any distance from the screen.
With no lenses (and very few other components), holographic projectors can be made very small, opening the door to highly portable video displays that might hold downloaded content to view almost anywhere—sort of like a video iPod with the ability to form a very large image on a screen or wall. This could mean the end of squinting at a portable DVD player's small LCD screen.
The researchers have formed a start-up company, Light Blue Optics, which is currently developing a prototype unit that accepts a composite signal and projects a 2-D image holographically. The holographic engine runs on a commercially available FPGA (field-programmable gate array) chip, which lets them reprogram it as they improve the algorithms. The company expects that commercial products could appear in two to four years. This research could even lead to true 3-D applications, though that will likely take quite a bit longer.