magneto-optical disk

hardware, storage Plastic or glass disks coated with a

compound (often TbFeCo) with special properties. The disk is

read by bouncing a low-intensity laser off the disk.

Originally the laser was infrared, but frequencies up to blue

may be possible; the shorter the wavelength the higher the

possible density. The polarisation of the reflected light

depends on the polarity of the stored magnetic field.

To write, a higher-intensity laser is used to heat the

material up to its Curie point, allowing its magnetisation to

be altered and "frozen" as it cools.

Storage FAQ.

(1995-03-15)