(CD-R) A write-once version of CD-ROM. CD-Rs can
hold about 650 megabytes of data. They are very durable and
can be read by normal CD-ROM drives, but once data has been
written it cannot be altered.
Standard prerecorded CDs have their information permanently
stamped into an aluminium reflecting layer. CD-R discs have a
dye-based recording layer and an additional golden reflecting
Digital information is written to the disc by burning
(forming) pits in the recording layer in a pattern
corresponding to that of a conventional CD.
The laser beam heats the substrate and recording layer to
approximately 250 C. The recording layer melts and the
substrate expands into the space that becomes available.
Phillips: New Technologies.
See also CD-RW and DVD-RAM.