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How Does Holographic Memory Work

  1. Aug 27, 2004 #1


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    Staff Emeritus

    I found this press release just yesterday and I'm curious to know how it works:

    http://www.optware.co.jp/english/what_040823.htm [Broken]

    In Figure 1:

    -Substrate 2 is just a protective cover for the cd.
    -The photo polymer is the recording layer, but which wavelength(color) is actually causing the polymerization for writing? And which one is reading the hologram?
    -The gap layers are just there to seperate the dichroic mirror.
    -The dichoric mirror is basically a wavelength filter that either reflects light or allows light to pass through.
    -Substrate 1 is just the shiny part of the cd that prevents the light from escaping. Why does the aluminum reflection layer have pits?
    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Aug 28, 2004 #2


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    Staff Emeritus


    Can anyone answer my questions?
  4. Aug 28, 2004 #3


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    The high frequency light source (blue) is used for writing (recording interference patterns) and reading these patterns. The low frequency light source (red) will be transmitted to the servo/tracking information etched on the aluminum reflector. Hence, "...preformatted address pits generate diffusion noise during read / write, thus deteriorate the signal quality", will be eliminated.


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