Blu-ray Drives

Blu-ray DVD Drive is used for playback of HD (High-Definition) video. It represents the 3rd gen of CD (Compact Disc) tech, after DVDs (Digital Video Discs) and audio CDs. In all 3 technologies, info is stored on a plastic disc 120 millimeters in diameter. The info is encoded in depths that form a twisting track on the disc. The blue laser, producing at 405 nanometers of wavelength, reads the pits. A Blu-ray disc can keep more data than an optical drive. An exclusive single-layer Blu-ray can keep 25 GB, and a double-layer holds 50 GBs. By difference, a single-layer DVD can hold only 4.7 GB.