DVD CDs (0.74 µm for DVD versus 1.6 µm for CD), accounting in part for DVD's increased storage capacity. In comparison, Blu-ray Disc, the successor to the DVD format, uses a wavelength of 405 nm (violet), and one dual-layer disc has a 50 GB storage capacity. Read and write speeds for the first DVD drives and players were 1,385 kB/s (1,353 KiB/s); this speed is usually called "1×". More recent models, at 18× or 20×, have 18 or 20 times that speed. Note that for CD drives, 1× means 153.6 kB/s (150 KiB/s), about one-ninth as swift. DVD-Video is a standard
Archival Disc intended as a consumer storage medium as of 2014, but is intended by the two companies as a solution for professional-level data archival. In order to reach a larger capacity whilst ensuring higher playback signal quality, the standard will employ crosstalk cancellation and partial response maximum likelihood (PRML) signal processing. Both companies will market the optical format under their respective brands. Sony will be using Archival Disc in within the Optical Disc Archive professional archival product range. Sony's aim is to create at least a 6TB storage medium. An emerging use case for Archival Disc has been projected for cold