LS-R economically viable. The need for the disc to be meticulously constructed from many layers of different materials, and the need for the drive to be able to electrically address each layer specifically, may make this solution too expensive for commercialization. In the next generation LS-R may compete with other next-generation optical disc format such as the Holographic versatile disc and Protein-coated disc formats. LS-R LS-R, or the Layer-Selection-Type Recordable Optical Disk, is the term coined by Hitachi in 2003 for a next-generation optical disc technology which allows much larger data storage densities than DVD, HD DVD or Blu-ray Disc, by
Optical disc to be used in the Library of Congress archiving efforts. The STC disks utilized a sealed cartridge with an optical window for protection . The CD-ROM format was developed by Sony and Denon, introduced in 1984, as an extension of Compact Disc Digital Audio and adapted to hold any form of digital data. The same year, Sony demonstrated a LaserDisc data storage format, with a larger data capacity of 3.28 GB. In the late 1980s and early 1990s, Optex, Inc. of Rockville, MD, built an erasable optical digital video disc system using Electron Trapping Optical Media (ETOM). Although this technology