Hardware Reference
In-Depth Information
Dr.T.FujiwarabegananintensiveresearchanddevelopmentprogramattheToshibaCor-
poration that eventually resulted in the perfection of floppy disk media optimized for per-
pendicular recording and the first commercially available magnetic storage devices using
the technique.
The first use of perpendicular recording in PCs was with the 3 1/2-inch, 2.88MB ED
(extra-high density) floppy format developed by Toshiba and officially announced in
1987,withtheEDdrivesanddisksfinallyreachingproductionin1989.IBMofficiallyad-
optedthesedrivesinitsPS/2systemsin1991,andanumberofmanufacturersbeganmak-
ing them for IBM and other PC manufacturers, including Toshiba, Mitsubishi, Sony, and
Panasonic. Because a 2.88MB ED drive can fully read and write 1.44MB HD disks (due
toBIOSmanufacturersfullyintegrating2.88MBfloppysupportintheBIOS)andbecause
DOS 5.0 and later included support for the 2.88MB format, the change to 2.88MB was
an easy one. Unfortunately, due to high media costs and a relatively low increase in data
capacity at a time when floppy disks were being replaced by writable CDs, these drives
never caught on.
Despite the 2.88MB ED floppy's failure in the marketplace, Toshiba and other companies
continued developing perpendicular magnetic recording for other media, especially hard
disk drives. Unfortunately, they would find that perpendicular recording technology was
too far ahead of its time when it came to hard drives, where the existing technology was
well entrenched, and where density evolution was already progressing at rates almost too
fast for the industry to assimilate. It would take almost 20 more years before the existing
longitudinal recording would begin to run out of steam as it reached 100Gb/sq. inch, and
the looming superparamagnetic limit would cause drive engineers to finally find justifica-
tion for switching to perpendicular recording.
In April 2002, Read-Rite Corporation, a major maker of read/write heads, reached areal
densities of 130Gb/sq. inch in a prototype drive using media provided by Maxtor sub-
sidiary MMC Technology. In November 2002, Seagate Technology announced it had
achieved areal densities of more than 100Gb/sq. inch in a prototype drive using this tech-
nology as well. According to two independent studies published in 2000, perpendicular
recording was projected to enable densities of up to 1,000Gb (1 terabit) per square inch in
the future, a prediction that is well on its way to becoming true.
Perpendicular recording finally became commercially available in hard disk drives on
August 16, 2005, when Toshiba's Storage Device Division announced shipment of the
world's first hard disk using PMR technology. These were 1.8-inch drives used primarily
in portable consumer electronics devices—most notably the Apple iPod media players,
but also found in some of the smallest laptop PCs, such as the Toshiba Libretto series.
Thefirst1.8-inchdrivesusingPMRwerethe40GBand80GBmodels, whichstore40GB
