Blue Lights Template

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Holographic Versatile Disc
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What is HVD?

• HVD is a new type of optical storage device
• HVD can store from 300 GB in 2008 up to 3.9 TB
• Normal DVD holds4.7 GB
• Developed by InPhase Tech Maxell

• Uses 2 lasers to read the same part of the disc
  by changing the angle of one laser

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Holographic?

• Leia in Star Wars is a volumetric display, not
  a holograph
• A hologram is a way to store 3 dimensional images

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How does it write the disc?

• Two beams are used, the reference beam and the
  information beam
• The reference beam remains unchanged, while the
  information beam is sent through a spatial light
  modulator

• The beams are recombined, creating an
  interference pattern of light

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Laser Beams?!?

• While one beam is used to reflect off the
  Dichroic mirror layer in the disc, another is
  used for servo
• This servo technology is the same used in CDs
  DVDs, using a 650nm laser to read address pits

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How does it read the disc?

• When the reference beam is shone onto the disc
  it returns the pre-recorded interference pattern
• The beam is then read by the cmos as a page at
  about 128MB/s

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Market Info

• Technology is slowly becoming easier to make,
  smaller discs will be available in a few years

HVDs can be mass produced effectively as data
can be pre-written when the disc is put together
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Questions?
The End