Thor-CD

Thor-CD was a proposed successor to the Compact Disc (CD) format, developed jointly by Sony and Philips in the late 1990s. It was primarily intended as a high-density optical disc format for video, specifically designed to compete with the DVD (Digital Versatile Disc) format.

Thor-CD employed a similar disc size as the CD but utilized a shorter wavelength laser (650nm, red) and higher numerical aperture optics to achieve a higher storage capacity, around 3 GB per side. This was significantly larger than the CD's 650-700 MB, but still considerably less than the initial 4.7 GB offered by DVD-5.

The format's name, "Thor-CD," was reportedly a provisional name used during development, alluding to Thor, the Norse god of thunder, and signifying the powerful improvement over the CD. It was later suggested that the final product might have been marketed under a different name if it had been released.

Despite its technical merits, Thor-CD ultimately failed to gain traction and was abandoned. Factors contributing to its demise included the rapidly increasing capacity of DVD, the complexities of manufacturing, the limited capacity compared to DVD, and the lack of industry support. DVD established itself as the successor to CD for video content and higher-capacity data storage, rendering Thor-CD obsolete before it could reach the market.