09-07-2012, 03:59 PM
FLUORESCENT MULTILAYER DISC
[attachment=27292]
INTRODUCTION
Fluorescent Multilayer
Disc, abbreviated as FMD,
is a data storage medium
that follows the idea
previously used in DVDs,
making multiple layers to
get more data on one disc,
but takes the idea to a new
level. Because the normal
reflective layers were too
limiting, making it nearly
impossible to get more
than two layers on a disc,
Constellation 3D decided to
find a new way to reflect
the light that would not
interfere with other layers.
To do this, they have a
different fluorescent
material in each layer
which reflects a different
frequency of light than the
other layers, making it
possible to shine the light
through the disc and read
the proper frequency for
the expected layer.
Because of this, the main
limitation on the number of
layers, besides how many
different materials can be
found to be used, would be
to keep the disc from being
too thick.
A 50 GB prototype disc was
demonstrated at the
Comdex industry show in
November 2000. First
generation FMDs were to
have roughly 100 GB per
disc.
OPERATING PRINCIPLES
The pits in an FMD are filled
with fluorescent material.
When coherent light from
the laser strikes a pit the
material glows, giving off
incoherent light of a
different wavelength. Since
FMDs are clear, this light is
able to travel through many
layers unimpeded.
FLUORESCENT MATERIAL
The fluorescent material .
arguably, the .main
ingredient. of FMD
technology converts
incident (incoherent) laser
light into incoherent
fluorescent light. C3D has
several material
formulations.
ADVANTAGES
1. The multi-layer system is
optically transparent and
homogeneous.
2. Low absorption in each
layer.
3. No absorption for the
emitted signal fluorescent
light.
4. Lower than CD/DVD
sensitivity to imperfections
in media and drives.
CONCLUSION
The rapid technological
development that is taking
place in storage devices
has also made the man
think about the needs and
the requirements for the
storage devices.
[attachment=27292]
INTRODUCTION
Fluorescent Multilayer
Disc, abbreviated as FMD,
is a data storage medium
that follows the idea
previously used in DVDs,
making multiple layers to
get more data on one disc,
but takes the idea to a new
level. Because the normal
reflective layers were too
limiting, making it nearly
impossible to get more
than two layers on a disc,
Constellation 3D decided to
find a new way to reflect
the light that would not
interfere with other layers.
To do this, they have a
different fluorescent
material in each layer
which reflects a different
frequency of light than the
other layers, making it
possible to shine the light
through the disc and read
the proper frequency for
the expected layer.
Because of this, the main
limitation on the number of
layers, besides how many
different materials can be
found to be used, would be
to keep the disc from being
too thick.
A 50 GB prototype disc was
demonstrated at the
Comdex industry show in
November 2000. First
generation FMDs were to
have roughly 100 GB per
disc.
OPERATING PRINCIPLES
The pits in an FMD are filled
with fluorescent material.
When coherent light from
the laser strikes a pit the
material glows, giving off
incoherent light of a
different wavelength. Since
FMDs are clear, this light is
able to travel through many
layers unimpeded.
FLUORESCENT MATERIAL
The fluorescent material .
arguably, the .main
ingredient. of FMD
technology converts
incident (incoherent) laser
light into incoherent
fluorescent light. C3D has
several material
formulations.
ADVANTAGES
1. The multi-layer system is
optically transparent and
homogeneous.
2. Low absorption in each
layer.
3. No absorption for the
emitted signal fluorescent
light.
4. Lower than CD/DVD
sensitivity to imperfections
in media and drives.
CONCLUSION
The rapid technological
development that is taking
place in storage devices
has also made the man
think about the needs and
the requirements for the
storage devices.