Optical disc of light. An early optical disc system existed in 1935, named . An early analog optical disc used for video recording was invented by David Paul Gregg in 1958 and patented in the US in 1961 and 1969. This form of optical disc was a very early form of the DVD (). It is of special interest that , filed 1989, issued 1990, generated royalty income for Pioneer Corporation's DVA until 2007 —then encompassing the CD, DVD, and Blu-ray systems. In the early 1960s, the Music Corporation of America bought Gregg's patents and his company, Gauss Electrophysics. American inventor James
5D DVD with a capacity of 10 terabytes, approximately 2000 times the capacity of a standard DVD, compared to Holographic Versatile Disc technology, which has an estimated maximum disc capacity of 6 terabytes. The similarity of disc writing would also make it easier to make 5D DVD players backwards-compatible with existing CD and DVD technology. 5D DVD A 5D DVD is a digital storage medium akin to a DVD being developed by Peter Zijlstra, James Chon and Min Gu at the Swinburne University of Technology in Melbourne, Australia. In 2009, the developers estimated that the technology could be commercially ready in five