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 drive CD, similar to the tray ejecting method used in internal optical disc drives of modern laptops and modern external slim portable optical disc drives. Like the top-loading mechanism, they have spring-loaded ball bearings on the spindle. Most internal drives for personal computers, servers and workstations are designed to fit in a standard 5.25" drive bay and connect to their host via an ATA or SATA interface. Additionally, there may be digital and analog outputs for audio. The outputs may be connected via a header cable to the sound card or the motherboard. At one time, computer software resembling CD players