How Does Holographic Memory Work

[dduardo]

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

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 separate 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?

 

[dduardo]

Bump

Can anyone answer my questions?

 

[dlgoff]

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.

Regards

Don