The
Clover Systems Dynamic Balance Analyzer is a tool for measuring
imbalance of DVD and CD discs.
Specification of disc imbalance was added to the Red Book
standard in 1999. Conformance to DVD and Red/Yellow/Orange Book standards can be
verified with this system.
The
advent of high-speed CD-ROM and DVD-ROM drives makes disc
unbalance an important issue.
The forces generated increase with the square of the
rotational rate, so at high speeds, the forces are extreme.
These forces and resultant vibration can adversely affect
disc performance and drive life.
High-speed
CD-ROM drives will reduce their read speed if they have trouble
reading the disc. One
of the causes of speed reduction is vibration caused by disc
unbalance. Only a properly balanced disc will provide the maximum
throughput these drives are capable of.
Disc
imbalance can be caused by thickness variation of the substrate,
lacquer coating, CD-R dye coating, or DVD bonding layer as well
as asymmetrical label design and
disc shape and center hole placement.
Molding optimization
