Innovation: Stacks more data

IBM scientists have unveiled multi-layer compact disks that offer huge gains in storage capacity. The disks are made by stacking two or more recording surfaces. At today's storage density, a 10-layer disk could store the equivalent of a million pages of printed text, with about a 10-second access time. To date, capacity increases in optical data storage have been due to increases in the density of information that could be written on a single disk surface.