Blu-spec CD describes an Audio CD manufactured by a proprietary process introduced by Sony in late 2008. Its name derives from the similar manufacturing process to that used to create Blu-ray Discs. Instead of a traditional infra-red laser, a blue laser is used for recording the pits on the CD master that is needed for disc replication. The blue laser creates more precise pits, causing less distortion in the optical read-out process.
A Blu-spec CD can be played on all CD players and does not require a blue laser to be read.