The Stacked Volumetric Optical Disc (or SVOD) is an

optical disc An optical disc is a flat, usuallyNon-circular optical discs exist for fashion purposes; see shaped compact disc. disc-shaped object that stores information in the form of physical variations on its surface that can be read with the aid o ...

format developed by

Hitachi Maxell , commonly known as Maxell, is a Japanese company that manufactures consumer electronics. The company's name is a contraction of "Maximum capacity dry cell". Its main products are batteries, wireless charging products, storage devices, (USB fl ...

, which uses an array of wafer-thin optical discs to allow data storage. Each "layer" (a thin

polycarbonate Polycarbonates (PC) are a group of thermoplastic polymers containing carbonate ester, carbonate groups in their chemical structures. Polycarbonates used in engineering are strong, toughness, tough materials, and some grades are optically transp ...

disc) holds around 9.4 GB of information, and the wafers are stacked in layers of 20, 25, 100, or more, giving a substantially larger overall data capacity; for example, 100× cartridges could hold 940 GB using the system as announced. Hitachi Maxell announced the creation of the SVOD standard in 2006, intending to launch it the next year. Aimed primarily at commercial users, the target price was ¥40,000 for a cartridge of 100 thin discs, with the potential to expand into the home user market. When they announced the system, Hitachi Maxell publicly recognized the possibility that the system could be eventually modified for use with a blue-violet laser, similar to

Blu-ray Blu-ray (Blu-ray Disc or BD) is a digital optical disc data storage format designed to supersede the DVD format. It was invented and developed in 2005 and released worldwide on June 20, 2006, capable of storing several hours of high-defin ...

discs, which could have expanded the capacity of the system to 3-5 TB. It is possible that they in fact developed this "second generation" SVOD for use with standard Blu-ray lasers, with each thin disc having a storage capacity of 25 GB, or a 100-disc cartridge having a storage of 5 TB. Hitachi Maxell developed systems both for

burning Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combust ...

to the media using standard DVD optical heads, and pre-recording to the media using a special heat imprint technique they called "nanoimprinting." Though nanoimprinting initially required 6 minutes per disc for pressing, they had improved it to 8 seconds, and intended to achieve a comparable throughput to standard DVD pressing. The primary application of the SVOD system seemed to be business data archival, replacing digital tape archives. In 2007, Japanese broadcaster

NHK , also known by its Romanization of Japanese, romanized initialism NHK, is a Japanese public broadcasting, public broadcaster. It is a statutory corporation funded by viewers' payments of a television licence, television license fee. NHK ope ...

announced a similar system, based on Blu-ray discs, of stacked optical storage media specifically designed to rotate at high speeds, up to 15,000 RPM. SVOD was anticipated to be a likely be a candidate, along with

Holographic Versatile Disc The Holographic Versatile Disc (HVD) is an optical disc technology that was expected to store up to several terabytes of data on an optical disc 10 cm or 12 cm in diameter. Its development commenced in April 2004. The technology was ...

s (HVDs), to be a next-generation optical disc standard. However, as of 2021, little has been done with the format.

References

External links

Hitachi Maxell develops wafer-thin storage disc
details and interview from IDG News Service (dead link, archived) (4 October 2006)

details in Japanese language (dead link, archived) (19 April 2006) Vaporware Rotating disc computer storage media Audio storage Video storage 120 mm discs DVD Optical discs {{compu-storage-stub