NASA SBIR 2004 Solicitation


PROPOSAL NUMBER: 04 X2.03-9461
SUBTOPIC TITLE: Wireless Power Transmission
PROPOSAL TITLE: Highly Efficient Fiber Lasers for Wireless Power Transmission

SMALL BUSINESS CONCERN (Name, E-mail, Mail Address, City/State/Zip, Phone)
Physical Sciences Inc
20 New England Business Ctr
Andover, MA 01810-1077

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Glen A Rines
135 South Road
Bedford, MA 01730-2307

We propose to develop ytterbium (Yb) fiber lasers with an electrical-to-optical efficiency of nominally 64% by directly coupling 80%-efficient diode lasers with Yb fiber laser structures that are capable of 80% optical-to-optical power conversion. These would be single spatial mode lasers, which are diffraction-limited light sources capable of long-range propagation in a narrow beam. As such they would provide a key technology element for wireless power transmission systems that are based on photovoltaic receiver technologies. The high efficiency diode lasers that form a key part of the proposed light source are currently being developed with DARPA funding under the Super High Efficiency Diode Sources (SHEDS) program. Yb fiber lasers have received a great deal of development effort in the broader laser community and have produced both the highest efficiencies and the highest output powers seen to date from fiber lasers. The innovation provided by this project would be the development of a simple, robust and highly efficient means of coupling the specific SHEDS diode structures to Yb fiber lasers by using laser micromachining to form an integral mirror and Brewster input port on the Yb fiber.

Specific NASA applications for wireless power transmission include the following:

? Transmission of power from solar panels located in earth orbit down to earth for terrestrial consumption;
? Transmission of power from earth to satellites to allow a longer operational lifetime for orbiting vehicles;
? Transmission of power to dark regions of the moon to power exploration and possibly mining enterprises in such locations;
? Transmission of power from a space-based power station to other space-based vehicles in need of additional power.

Military applications include:

? Remotely powering small, unmanned aircraft used to guard a combat area or as an advance scout for moving convoys;
? Remotely powering high-altitude, long-endurance aircraft
? Supplying substantial amounts of power to troops and equipment located in a remote inaccessible area.

Commercial applications of this technology include:

? Wireless power transmission could be applied anywhere that it is impractical to run conventional land lines and the benefits of powering the remote location justify the cost of the installation.
? Unmanned non-military surveillance activities of a commercial nature could benefit from remotely powered aircraft.