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Holographic Versatile Disc

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The Holographic Versatile Disc (HVD) was a proposed optical disc technology designed to store up to several terabytes of data on a 10 cm or 12 cm diameter disc. Development began in April 2004, but the project was ultimately abandoned due to funding issues. One of the companies responsible for its development went bankrupt in 2010.[2]

The smaller disc size was aimed to reduce costs 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 read 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 servo information from a regular CD-style aluminium layer near the bottom. Servo information 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 servo information 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 the actual high costs of the drives and discs, lack of compatibility with existing or new standards, and competition from more established optical disc Blu-ray and video streaming.

Technology

Estructura del disco holográfico versátil : 1.  Láser de escritura/lectura verde (532  nm) 2.  Láser de posicionamiento/direccionamiento rojo (650  nm) 3.  Holograma (datos) (mostrado aquí en marrón) 4.  Capa de policarbonato 5.  Capa fotopolimérica (capa que contiene datos) 6.  Capas de distancia 7.  Capa dicroica (que refleja la luz verde) 8.  Capa reflectante de aluminio (que refleja la luz roja) 9.  Base transparente P.  Patrón de hoyuelos (La ilustración no está a escala).

El almacenamiento óptico actual guarda un bit por pulso, y la alianza HVD esperaba mejorar esta eficiencia con capacidades de alrededor de 60 000 bits por pulso en una forma de cono truncado invertido con un diámetro de 200 μm en la parte inferior y de 500 μm en la parte superior. Se pueden lograr altas densidades acercando estos elementos en las pistas: 100 GB con una separación de 18 μm, 200 GB con 13 μm, 500 GB con 8 μm, y la más demostrada de 5 TB para 3 μm en un disco de 10 cm.           

El sistema utilizaba un láser verde con una potencia de salida de 1 vatio , lo cual es una potencia elevada para un láser de consumo. Entre las posibles soluciones se incluyen mejorar la sensibilidad del polímero utilizado o desarrollar y comercializar un láser con mayor potencia de salida que sea adecuado para un dispositivo de consumo.

Tecnologías competidoras

HVD no es la única tecnología en medios de almacenamiento holográfico de alta capacidad. InPhase Technologies estaba desarrollando un formato holográfico rival llamado Tapestry Media , que según afirmaban, eventualmente almacenaría 1,6  TB con una tasa de transferencia de datos de 120 MB/s, y varias empresas están desarrollando discos de nivel TB basados ​​en tecnología de almacenamiento óptico de datos 3D . Estas grandes capacidades de almacenamiento óptico compiten favorablemente con el formato Blu-ray Disc . Sin embargo, en 2006, se proyectaba que las unidades holográficas costarían inicialmente alrededor de US$15.000, y un solo disco alrededor de US$120–180, aunque se esperaba que los precios bajaran constantemente. [ 7 ] Dado que InPhase Technologies no pudo entregar el producto prometido, se quedaron sin fondos y quebraron en 2010. [ 8 ]

Foro de Desarrollo de Sistemas de Holografía

El Foro de Desarrollo de Sistemas de Holografía (HSD Forum; anteriormente conocido como HVD Alliance y HVD FORUM) es una coalición de empresas cuyo objetivo es proporcionar un foro industrial para las pruebas y el debate técnico de todos los aspectos del diseño y la fabricación de sistemas HVD.

A marzo de 2012, las siguientes empresas son miembros del foro: [ 9 ]

As of March 2012, the following companies are supporting companies of the forum:

  • Kodate Laboratory

Standards

On December 9, 2004, at its 88th General Assembly, the standards body Ecma International created Technical Committee 44, dedicated to standardizing HVD formats based on Optware's technology.

On June 11, 2007, TC44 published the first two HVD standards:[10] ECMA-377,[4] defining a 200 GB HVD "recordable cartridge" and ECMA-378,[5] defining a 100 GB HVD-ROM disc. Its next stated goals were 30 GB HVD cards and submission of these standards to the International Organization for Standardization for ISO approval.[11]

General Electric

General Electric Global Research Centers created a holographic disc that could hold many times the data of a Blu-Ray — up to 500 GB.[12] As the technology is quite similar to CD, DVD, and Blu-ray technologies, the players were to be cross-compatible with these formats.

See also

References

  1. ↑Stair, Ralph; Reynolds, George (January 2015). Principles of Information Systems. Cengage Learning. 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. 12"Information Interchange on Holographic Versatile Disc (HVD) Recordable Cartridges – Capacity: 200 Gbytes per Cartridge". ECMA-377.
  5. 12"Information Interchange on Read-Only Memory Holographic Versatile Disc (HVD-ROM) – Capacity: 100 Gbytes per disk". ECMA-378.
  6. ↑"Maxell focuses on holographic storage". CNET News.com. November 28, 2005. Retrieved May 28, 2007.{{cite web}}: CS1 maint: deprecated archival service (link)
  7. ↑"Hitachi-Maxell to Ship Holographic Storage this Year". DailyTech. August 3, 2006. Archived from the original on March 6, 2012. Retrieved May 28, 2007.
  8. ↑"Holographic storage bites the dust". ZDNet. Archived from the original on May 22, 2010.
  9. ↑"HSD FORUM - HSDフォーラムについて / 会員リスト". Archived from the original on March 13, 2012.
  10. ↑"Ecma releases new Holographic Information Storage Standards". Ecma press release. July 4, 2007.
  11. ↑"Ecma standardizes Holographic Information Storage"(PDF). Ecma press release. January 26, 2005.
  12. ↑Ganapati, Priya (April 27, 2009). "GE Holographic Breakthrough Squeezes 100 DVDs Into a Single Disc". Wired. Retrieved January 8, 2019.
  • コリニア方式ホログラフィーの原理と応用展開 aka Collinear Holography/Principle and Applications – the original essay (in Japanese) that explains the technical details of HVD.
  • How Stuff Works – explains how HVD works.
  • Optware – the company that created and owned the rights to the HVD format.
  • InPhase – a company, now bankrupt, that developed a competing holographic storage format.
  • DaTARIUS signs agreement with InPhase Technologies to be their sole sales, service and support supplier of Tapestry Media hardware and media to ship starting in 2007 (300 GB WORM discs) with 600 GB discs and re-writable technology in 2008 as well as 1.6 TB media available in 2010.
  • Holography system rides single beamEE Times, February 27, 2006 – interview with Hideyoshi Horimai and Yoshio Aoki of Optware Corp.
  • Holographic storage standards eyedEE Times, February 28, 2006 – article about the upcoming technical committee meeting to begin standardization of HVD.
  • Video explaining holographic storageArchived December 1, 2008, at the Wayback Machine – PC Magazine, October 4, 2006
  • Elusive Green Laser Is Missing IngredientWall Street Journal, February 13, 2008
  • General Electric unveils 500GB optical disc storage