Chiral Film
Summary:
Reveo, Inc. (Elmsford, NY), has developed a chiral film to be used to produce optical compact discs (CDs) with capacities up to 1,000 times greater than today’s models. The key to such extraordinary performance characteristics is a multi-layered structure of chiral film placed on the optical disc, developed with the help of BMDO. Reveo has created a subsidiary, CLCEO, Corp., to specialize in the optical storage market using this technology and is soliciting strategic partners to develop product lines.
Technology Description:
Reveo, Inc. (Elmsford, NY), has developed a chiral film to be used to produce optical compact discs (CDs) with capacities up to 1,000 times greater than today’s models. Such discs will also allow greater retrieval speeds as well.
The key to such extraordinary performance characteristics is a multi-layered chiral film placed on the CD. Current CDs and digital versatile disc (DVDs) have one surface layer that a laser can read. Reveo is creating a multi-layer technology through the use of chiral films, made either from cholesteric liquid crystals (CLCs) or vacuum-deposited inorganic materials. The chiral films can be made to selectively reflect light that matches a particular polarization state and characteristic wavelength while transmitting all other wavelengths at near-zero loss. The films are stacked on top of each other to make what Reveo calls storage “decks.” Data on individual decks are read by varying the depth of focus and/or wavelength of the tunable read laser.
Thus far, the company has demonstrated a system in which data can be read from six “layers” using three wavelengths with two polarizations. A two-fold improvement in data capacity is possible in the near-term, utilizing the polarization characteristics of chiral films at one wavelength. Eventually, a Reveo chiral-coated disc, read with a tunable laser, could hold as many as 1000 information-carrying layers. Reveo has recorded data marks as small as 0.3 micrometers. If an infrared (0.78um) laser is used for data retrieval, a 10-mm–thick disc of diameter 120mm would have a storage capacity of 650 gigabytes (in comparison, today’s CD systems can offer approximately 650 megabytes per disc). The Reveo disc would have an equivalent volumetric density of 7 gigabytes/cm(3). Plus, the proposed optical storage technology can utilize advances in short-wavelength diode lasers (i.e. the predicted blue-light lasers) to increase the storage capacity even further.
In addition to greater data-holding capacity, the use of selective reflectance and polarization opens the door to the parallel reading of layers, a technique that could significantly increase the read speed of an optical disc. Thus far, this technology has been demonstrated with the simultaneous use of both wavelength division multiplexing (WDM) and polarization discrimination multiplexing (PDM) of read-channel signals. With this method, a data transfer rate greater than 150 gigabytes would be possible (the fastest DVD players today can only read 2.6 gigabytes per second).
To demonstrate the salient features of this ultrahigh capacity and ultrafast retrieval optical storage technology, Reveo has designed a prototype optical storage system. Reveo’s design would allow for backward compatibility, or the ability for new chiral-reading components designed to read older CDs as well, thereby providing a natural and viable migration path for rapid introduction to the market.
MDA Origins:
BMDO funded SBIR work to develop chiral film technology for ultrahigh capacity and ultrafast retrieval optical storage. BMDO is interested in performance gains for its Battle Management/Command, Control, Communications, Computers, and Intelligence systems.
Spinoff Applications:
When fully developed, this technology could be used by the data-storage industry as part of an optical storage system to replace computer CDs and DVDs. Chiral-based discs would have the clear advantage of holding greater amounts of data, although they are predicted to be more expensive to manufacture. The home entertainment industry could also benefit, as optical discs could hold audio and video products with higher resolution and more compactly than current formats.
Other applications for chiral films exist in optical communications. Chiral films can be used in such optical components as waveguides, couplers, and dense wavelength division multiplexing (DWDM) systems.
Commercialization:
Reveo has developed proprietary techniques to reliably manufacture high-quality CLC films of uniform thickness. The company is also addressing disc production issues. At present CLCEO is pursuing strategic partners to develop product lines for specific applications.
Eventually the company plans to demonstrate the technology to optical storage manufacturers, both for computer and home entertainment applications. According to UK industry analyst firm Understanding & Solutions Ltd, the computer CD-ROM pressing industry turns out about 2.7 billion discs per year, with an annual growth rate of 35 percent. At present, the cost of a blank CD for manufacturers runs about 10–15 cents each (eventually its market will migrate towards DVDs). This market has a constant demand for portable storage mediums that can hold ever larger amounts of data. The home entertainment market also is quite large. Global music sales amount to $38.5 billion annually, according to the Recording Industry Association of America. The U.S. alone accounts for sales of 502 million units, 70 percent of which are CDS.
Reveo has attracted over $4 million in funding for this project, from such sources as NASA and the U.S. Air Force, in addition to BMDO. Reveo’s subsidiary, CLCEO Corp., will specialize in the optical storage market. For the optical communications market, quarter-wave plates and linear and circular polarizers for optical switching have been developed as byproducts of Reveo’s BMDO work. A separate patent has been issued for polarizer devices.
Company Profile:
Founded in 1991 by Dr. Sadeg Faris, Reveo is an R&D company working on a wide variety of experimental projects, including stereoscopic imaging, fuel cells, and smart materials. The company is headquartered in Elmsford, NY, with laboratory facilities and subsidiaries in Hawthorne, NY, and Sunnyvale, CA. Reveo and subsidiaries have over 100 employees, of which more than 30 hold advanced degrees in science and technology.
Contact Information:
Sarah Peach, Ph.D.
Business Development Manager
Reveo, Inc. (laboratory)
8 Skyline Drive
Hawthorne NY 10532
Tel:914-345-9556
Fax:914-345-2095
email: peach@reveo.com
Reveo, Inc. (headquarters)
85 Executive Blvd.
Elmsford NY 10523
Tel:914-345-9555
Fax:914-345-9558
web: www.reveo.com
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