| Fluorescent
Multi-layer Disc
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Introduction
Requirements
for removable media storage devices (RMSDs) used with personal computers have
changed significantly since the introduction of the floppy disk in 1971. At one
time, desktop computers depended on floppy disks for all of their storage requirements.
Even with the advent of multigigabyte hard drives, floppy disks and other RMSDs
are still an integral part of most computer systems, providing. ¢
Transport between computers for data files and software
¢ Backup to preserve
data from the hard dive
¢ A way to load the operating system software
in the event of a hard failure. Data storage
devices currently come in a variety of different capacities, access time, data
transfer rate and cost per Gigabyte. The best overall performance figures are
currently achieved using hard disk drives (HDD), which can be integrated into
RAID systems (reliable arrays of inexpensive drives) at costs of $10 per GByte
(1999). Optical disc drives (ODD) and tapes can be configured in the form of jukeboxes
and tape libraries, with cost of a few dollars per GByte for the removable media.
However, the complex mechanical library mechanism serves to limit data access
time to several seconds and affects the reliability adversely.
Most information is still stored in non-electronic form, with very slow access
and excessive costs (e.g., text on paper, at a cost of $10 000 per GByte).Some
RMSD options available today are approaching the performance, capacity, and cost
of hard-disk drives. Considerations for selecting an RMSD include capacity, speed,
convenience, durability, data availability, and backward-compatibility. Technology
options used to read and write data include. ¢
Magnetic formats that use magnetic particles and magnetic fields.
¢ Optical
formats that use laser light and optical sensors.
¢ Magneto-optical and
magneto-optical hybrids that use a combination of magnetic and optical properties
to increase storage capacity.
The introduction
of the Fluorescent Multi-layer Disc (FMD) smashes the barriers of existing data
storage formats. Depending on the application and the market requirements, the
first generation of 120mm (CD Sized) FMD ROM discs will hold 20 - 100 GigaBytes
of pre -recorded data on 12 - 30 data layers with a total thickness of under 2mm.In
comparison, a standard DVD disc holds just 4.7 gigabytes. With C3D's (Constellation
3D) proprietary parallel reading and writing technology, data transfer speeds
can exceed 1 gigabit per second, again depending on the application and market
need.
WHY FMD? Increased
Disc Capacity
DVD data density (4.7 GB) on each layer of data carriers up
to 100 layers. Initially, the FMD disc will hold anywhere from 25 - 140 GB of
data depending on market need. Eventually a terabyte of data on a single disc
will be achievable. Quick Parallel Access and
Retrieval of Information
Reading from several layers at a ime and multiple
tracks at a time nearly impossible using the reflective technology of a CD/DVD
- is easily achieved in FMD. This will allow for retrieval speeds of up to 1 gigabyte
per second. Media Tolerances
By using incoherent
light to read data the FMD/FMC media will have far fewer restrictions in temperature
range, vibration and air- cleanness during manufacturing. And will provide a considerably
more robust data carrier than existing CD and DVDs. <<back |