Cool
cd rom player!
Quite impressive
design.
CD-ROM (an abbreviation of "Compact Disc read-only
memory") is a Compact Disc that contains data
accessible by a computer. While the Compact Disc format
was originally designed for music storage and playback,
the format was later adapted to hold any form of binary
data. CD-ROMs are popularly used to distribute computer
software, including games and multimedia applications,
though any data can be stored (up to the capacity limit
of a disc). Some CDs hold both computer data and audio
with the latter capable of being played on a CD player,
whilst data (such as software or digital video) is
only usable on a computer (such as PC CD-ROMs). These
are called Enhanced CDs.
Data is stored on the disc as a series of microscopic
indentations ("pits", with the gaps between
them referred to as "lands"). A laser is
shone onto the reflective surface of the disc to read
the pattern of pits and lands. Because the depth of
the pits is approximately one-quarter to one-sixth
of the wavelength of the laser light used to read the
disc, the reflected beam's phase is shifted in relation
to the incoming beam, causing destructive interference
and reducing the reflected beam's intensity. This pattern
of changing intensity of the reflected beam is converted
into binary data...
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