Fabricacion De Cds, English

CD & DVD MANUFACTURING PROCESS
INTRODUCTION
CD is the abbreviation for Compact Disc. CDs are an optical disc used to store digital data (audio, images, video, documents…) A standard CD has 12 cm ofdiameter and can storage 700 Mb. The technology was expanded afterwards to encompass data storage (CD-ROM), write-once audio and data storage (CD-R), rewritable media (CD-RW), Video Compact Discs(VCD), Super Video Compact Discs (SVCD), PhotoCD, PictureCD, CD-i, and Enhanced CD. Audio CDs and audio CD players have been commercially available since October 1982.
DVDs are optical discs storagemedia format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than CDs while having the same dimensions. There are also different kinds ofDVDs depending on the intended use. DVD-ROMs are used to storage data and can only be read. DVD+R and DVD-R can be recorded only once using optical disc recording technologies. Rewritable DVDs (DVD-RW,DVD+RW, and DVD-RAM) can be recorded and erased multiple times.
The main difference between these two optical dics is the capacity of storage that they have. While CDs can only store 700 Mb, DVDusually can store from 4,7 Gb up to 17 Gb. This is the result of differences in their manufacturing processes that will be explained in the following sections.

CD - DVD diferenciesMANUFACTURING PROCESS
Compact Disc manufacturing is a process by which CDs are replicated from a master version created from a source recording. It differs from burning as the pits and lands are mouldedinto a CD blank instead of being ‘burn marks’.
Compact Discs are actually copies from an original glass master disc. The process by which CDs are manufactured and replicated in mass quantities isnowadays completely automated. A single factory is able to product 100 000 units per day.
The process begins when a laser machines cuts glass master discs and the information is recorded on what it...