multilevel optical disc
An optical disc technology that uses multiple platters sandwiched together with a tiny spacer between them. The different layers are accessed by moving the lens up and down and focusing on one of the disk surfaces. IBM demonstrated this technology in 1994 at its Almaden Research Center in San Jose, CA, and showed its feasibility with various optical technologies. In 2001, multilevel CD drives and media were introduced.
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| Multilevel Optical Disc |
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| Using multiple layers of recording within the disc's surface yields higher capacities. Using two layers, the capacity of a CD or CD-ROM is increased from 700MB to 2GB. |