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Researchers at Bellcore have created a holographic system for high speed data retrieval using an array of 1000 semiconductor lasers on a chip to retrieve holographic images stored in a single crystal. Unfortunately, the researchers have only retrieved a few images – ultimately they hope to get up to 1000 images from a crystal. Another company, Microelectronics and Computer Technology, is working on a method of storing holographic images in crystallite arrays rather than the single crystals used by Bellcore. Eventually, the holographic images could be used for data storage. While 1000 lasers on a chip is impressive, IBM recently developed a two inch chip holding 20,000 lasers. The ability to put 20,000 lasers on a chip promises a lot for technologies like laser printing, CD-ROM, and fiber optic information transmission.

The memory world has two new technologies, one from IBM and one from SHRAM. IBM showed the "Lightning" SRAM (static RAM) chip at the IEEE conference in February. The chip holds up to 512K of information and can send and receive eight billion bits per second, a feat achieved by having the chip carry out read and write operations simultaneously. SHRAM announced Sheet RAM, which is composed of a ferromagnetic layer on top of a neutral substrate. A single Hall-effect (no idea what that is, sorry) transistor sits on top of the ferromagnetic layer for each memory cell, a scheme somewhat similar to core memory, with its magnetic donuts on interlaced wires. Sheet RAM resembles core memory in that it stores bits by changing magnetic polarity, though of a region rather than a discrete donut. Since Sheet RAM is nonvolatile and probably relatively easy to produce, it could become an excellent form of fast, permanent storage.

Olivetti announced a line of portable PC-clones that are distinguished from the rest of pack by removable keyboards and built-in touch pads for cursor control. One of the problems with laptop and notebook computers is that they can seldom use a mouse. Microsoft’s BallPoint (which has been well received so far) helps to address the problem of graphical input, but it’s definitely an add-on, in comparison to Olivetti’s built-in touch-pads.

I love new input devices, and BioControl Systems of Palo Alto may have one of the best so far. It’s a device mounted on a headband that monitors the electrical field movement of your eyes and moves an object on the screen accordingly. BioControl Systems is looking for capital to go beyond the current prototype, possibly first into video game control, but eventually into mouse-type manipulations. It sounds like a wonderful idea, but could play havoc with your eyes after a while.

Related articles:
COMMUNICATION WEEK — 04-Feb-91, pg. 22
BYTE — Jan-91, pg. 20
BYTE — Mar-91, pg. 28
PC WEEK — 11-Mar-91, Vol. 8, #10, pg. 22
InfoWorld — 11-Mar-91, Vol. 13, #10, pg. 24
BYTE — Mar-91, pg. 32

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