Phase Change Dual (PD)

A technology for recording rewritable compact discs that was developed by Matsushita Electric Industrial Co. of Osaka, Japan. The PD phase change on tiny disc crystals is achieved with a laser beam burning that makes them more or less reflective. The PD rewritable discs, however, cannot be read on standard CD-ROM players. This limits the market for developers. However, the rewritable feature has many useful attributes. The capacity of a PD disc is currently 650 MB and the player/recorder sells for less than $1,000. (See also CD )