Holographic Versatile Disc
| Storage medium Holographic Versatile Disc (HVD)
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| General | |
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| Type | Optical storage medium |
| capacity | up to 3.9 TB |
| size | 12 cm |
| origin | |
| developer | Optware, Fuji Photo , CMC Magnetics |
| Launch | Development stopped |
| predecessor | Blu-ray Disc , HD DVD , VMD |
The Holographic Versatile Disc , or HVD for short , was an experimental holographic storage medium . Similar to the Compact Disc , DVD and Blu-ray Disc , it would have been read and written by laser . The product should originally have appeared on the market in 2008, but it never happened. In 2010 the main developer of the format, InPhase Technologies , was closed due to insolvency.
technology
1. green read / write laser (532 nm)
2. red positioning and addressing laser (650 nm)
3. hologram (data)
4. polycarbonate
layer 5. photopolymeric layer (data carrier layer)
6. spacer layers
7. dichroic layer (reflects green light)
8. aluminum layer (reflects red light)
9. transparent base
P. Pit
The Holographic Versatile Disc was planned as the next generation of optical storage media after the Blu-ray Disc . Two lasers were to be used, one red and one blue-green; an overlay of the two would have illuminated a certain point on the data carrier. The blue-green laser would have read data encoded as a laser interference pattern from a holographic layer in the upper area of the storage medium, while the red laser would have been used to read auxiliary information from an ordinary reflective aluminum layer in lower layers. The auxiliary information should serve to determine where you are currently on the disc, comparable to sector, head and segment information on a normal hard drive . In the case of a CD or DVD , this auxiliary information is distributed between the user data. A dichroic mirror layer between the holographic data and the auxiliary data should reflect the blue-green laser and let the red laser through. This would have been an advance over other holographic storage media , which either had too much interference or had no auxiliary data.
HVDs should have reached a capacity of up to 3.9 terabytes , which would have been about eight times the size of the largest experimental Blu-ray Disc (500 GB, conventional Blu-ray discs use 25 or 50 GB). However, only 300 GB was planned for the beginning. In addition, a read rate of 1 Gbit / s should have been achieved with a single rotation speed (compared to 36 Mbit / s for Blu-ray Disc, 10.8 Mbit / s for DVD and 1.41 Mbit / s for CD) . This would have made it the first optical storage system whose read rate would have been comparable to hard drives of the time.
specification
The specifications for the holographic storage medium called Holographic Versatile Disc were decided in December 2004 at the 44th meeting of the Technical Committee (English Technical Committee , hence also TC44 for short ) of Ecma International .
Since December 2004 the following companies and organizations have worked together in the HVD Alliance (later HVD Forum, then Holography System Development Forum):
- CMC Magnetics
- Fujifilm
- Hitachi
- IBM
- Optware
- Panasonic
- Philips
- Pioneer
- Sony
- Stanford University
- Texas Instruments
- Toshiba
However, the organization's website has not been available since 2013.
See also
Web links
Individual evidence
- ^ Robin Harris: Holographic storage bites the dust. In: ZDNet. February 18, 2010, accessed May 16, 2015 .
- ↑ TC44 - Holographic Information Storage Systems (HISS) ( Memento of the original from March 13, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (English) - (forwarding) page at Ecma International ; Status: March 1, 2012 (accessed on: March 1, 2012)
- ↑ a b HSD FORUM - HSD と は / 技術 情報 ( Memento from July 26, 2011 in the Internet Archive ) (English / Japanese) - Page at the HSD forum ; Status: March 1, 2012 (accessed on: March 1, 2012)
