magneto-optical disc« BACK TO DICTIONARY INDEX
(n.) A high-density, read/write optical storage medium. In access speed, it is slower than a hard disk but faster than a CD-ROM. A disc is written by a laser that heats a spot on the disc surface. The spot is polarized by an electromagnet from the other side of the disc. When the disc is read, the change in polarity alters the reflection of light from the reading laser at that spot, and the difference is interpreted as a data value. A magneto-optical disc may be written and read many times, as if it were a large floppy disk.