CD Audio / CD ROM

A compact disc (CD) is a polycarbonate injection moulded disc with a metal layer capable of storing digital information (mostly audio).

It has a storage capacity of approx 74 minutes playing time.

Compact Disc Read Only Memory-type of optical disc is similar to an audio compact disc, but it contains computer data and has a storage capacity of approx 700mb.

The Process

	Just like a DVD, glass mastering is the first process where we convert the clients pre-mastered disc or tape to a glass master from which stampers are created.

	The stamper is mounted into theinjection moulding machine and conditioned polycarbonate granules are fed into the hopper of the injection screw

	The granules are heated to 345 degrees Celsius to produce a molten liquid which is injected into the mould cavity and forms around the protruding pit structure on the stamper.

	Cooling channels open the mould solidifying the moulding plastic into a 1.2mm solid polycarbonate disc, containing an exact reverse replica of the stamper’s pit structure

	The moulded user data is now placed in a high vacuum chamber where a thin coat of aluminium is laid down over the pit surfaces. This is called ‘Metalising’ followed by a clear acrylic protective layer.

	The disc undergoes a physical inspection by camera to ensure the cosmetic criteria is within specification

	The approved finished discs (stacked on a spindle) are ready for electrical and mechanical off-line testing in our Quality Control Department.

	Once approved the quality assured discs are now ready for printing and packing.

CD Glass Mastering input media

Format	Input Media
CD Audio	CD-R and Exabyte Tape

CATEGORIES

CD Audio / CD ROM