Magnetic recording will run out of gas by 2001, claims Jim Porter of data storage analysts Disk/Trend. In the past year, however, several new technologies have been announced which promise to continue the ascent of disk density and prolong the life of Winchester technology, the name given to the generic assembly of components that make up today’s disk drives.
By Nat Tunbridge
One potential breakthrough comes from start-up company Quinta Corp. Although the company’s Optically Assisted Winchester (OAW) technology is yet to go into production, its promise was enough to convince Seagate Technology Inc to purchase Quinta for $230m in 1997. OAW uses many of the key components of the Winchester system, but enhances it in several key areas. Lasers are used instead of magnetic technology and new materials are also used for the recording media. The OAW laser beams are generated by an optical switch module, which sends pulses of laser light along a network of fiber optics not much thicker than a human hair. This fiber optic network carries the laser light along the actuator arms that support the read/write head and, at the end of the arm, the light is reflected through tiny micro-machined mirrors to the lenses inside the head. These lenses focus the laser light through a magnetic coil to write on the media surface. Quinta claims that each stage of the OAW process will offer innovations and benefits. The angle of the micro-machined mirrors at the end of the arm, for instance, can be altered by an electrical current. This means the laser’s destination on the media surface can be shifted by minute increments, which enables more data tracks to be recorded. Quinta says densities exceeding 100,000 tracks per inch (tpi) are possible, compared with an average of 10,000 tpi today. Because these lenses are so tiny and because fiber-optic technology is so light, the head is also much smaller and more maneuverable than existing Winchester technology. The micro-optic lenses inside the head are only 350 microns in diameter, so the laser beam that is focused onto the media surface is much smaller than the equivalent mark from a magneto- resistive head, allowing for more data to be recorded in a given area. Quinta is also promising that plastic media can be used in an OAW drive, which is lighter and less expensive than the aluminum traditionally used in Winchester products. The OAW media is also purportedly based on rare-earth transitional metal alloys – metals that can be broken down to the atomic level – which enables smaller bit cells to be created, thus allowing more data to be packed onto a disk. But although Seagate clearly has faith in the validity of the OAW premise, Quinta has not announced any products yet. The company stated in September 1997 that product plans would be available in May 1998, but this has now been revised to the end of the year. Analysts have suggested 1999 may be a more realistic date. Analysts have also questioned whether there will be a sufficient market for OAW. I don’t see a significant enough price differential and I don’t see performance to rival current Winchester technology, says John McArthur, a storage analyst with market researchers IDC. Although exact prices are not available for OAW technology, it is generally believed that the complex mechanics involved will make it more expensive than magnetic Winchester technology. There are also technical barriers. One key problem is the signal-to-noise ratio, admits Phil Montero, corporate marketing manager for Quinta. That’s an issue that will always challenge us. The signal-to-noise ratio is an expression of how clearly the signal is received, versus its integrity when it was sent.
Computer Business Review.
