Holographic Versatile Disc

Holographic Versatile Disc
An HVD by Optware
Media typeUltra-high density optical disc
Capacity3.9 TB[1]
Developed byHSD Forum
UsageData storage, high-definition video, QHD/WQHD, possibility of Ultra HD

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 yet became abandoned due to funding issue. One of the company responsible for HVD went bankrupt in 2010.[2]

The reduced radius was meant to reduces cost and materials used. It employs a technique known as Collinear Holography, whereby a blue-green and red laser beam are collimated in a single beam. The blue-green laser reads data encoded as laser interference fringes from a holographic layer near the top of the disc. A red laser is used as the reference beam to read servoinformation from a regular CD-style aluminium layer near the bottom. Servoinformation is used to monitor the position of the read head over the disc, similar to the head, track, and sector information on a conventional hard disk drive. On a CD or DVD this servoinformation is interspersed among the data. A dichroic mirror layer between the holographic data and the servo data reflects the blue-green laser while letting the red laser pass through. This prevents interference from refraction of the blue-green laser off the servo data pits and is an advance over past holographic storage media, which either experienced too much interference, or lacked the servo data entirely, making them incompatible with current CD and DVD drive technology.[3]

Standards for 100 GB read-only holographic discs and 200 GB recordable cartridges were published by ECMA in 2007,[4][5] but no further holographic disc product has ever appeared in the market. A number of release dates were announced, all since passed,[6] likely due to actual high costs of the drives and discs itself, lack of compatibility with existing or new standards, and competition from more established optical disc Blu-ray and video streaming.

  1. ^ Stair, Ralph; Reynolds, George (January 2015). Principles of Information Systems. ISBN 9781305482210.
  2. ^ "Holographic storage bites the dust". ZDNET. February 18, 2010. Retrieved January 4, 2021.
  3. ^ "What's New". August 23, 2004. Archived from the original on October 9, 2004.
  4. ^ Cite error: The named reference ecma-377 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference ecma-378 was invoked but never defined (see the help page).
  6. ^ "Maxell focuses on holographic storage". CNET News.com. November 28, 2005. Archived from the original on July 22, 2012. Retrieved May 28, 2007.

Holographic Versatile Disc

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