Fujitsu has developed a new read/write disk-head technology that will enable hard-disk drive recording densities of up to 300Gbits per square inch.

An increase in recording densities offers notebook and desktop computer manufacturers a route to offering higher storage capacities, usually for only a slight increase in price.

Current 2.5-inch hard disks can store around 30GB per disk platter. When Fujitsu commercializes its technology in two-to-four years' time it will lead to capacities of 180GB per platter, six times current capacities, Fujitsu said.

The breakthrough technology is known as Current-Perpendicular-to-Plane mode Giant Magneto-Resistive (CPP-GMR) heads, these are more sensitive to signals and can read and write data bits three times more compactly than existing GMR heads, which are characterized as Current-in-Plane mode.

Disk boom Fujitsu expects to commercially produce drives based on CPP-GMR heads within two years for use in computers, and particularly in the expected boom market for disk-drive-based consumer electronics products such as game consoles, MP3 players and personal video recorders (PVRs).

High-capacity 2.5-inch hard drives will eventually make 3.5-inch drives obsolete, Fujitsu claims.

Disk-storage capacity has improved even faster than processing power over the last decade, according to the International Disk Drive Equipment Manufacturers Association (IDEMA).

However, manufacturers have found it hard to turn their technical expertise into profit. The price of hard disk storage has fallen from $11.54 per MB in 1988 to $0.01 per MB today. The number of independent manufacturers has fallen from 75 to 13, IDEMA said.