SBIR-STTR Award

We propose to develop kilowatt fiber lasers that is highly efficient at the conversion of electrical power into a diffraction-limited laser beam. The overall goal of this program is to deliver an unprecedented kilowatt-class fiber laser. The laser will be compact in size and light in weight. The goals of the Phase I are to use the newly developed beam shaping technology to combine the power from multiple laser diodes to small laser fiber aperture, perform a feasibility study of the enabling technology, and validate our approach by the design, analysis and fabrication of a prototype for use in a proof-of-principle demonstration. Specifically, the Phase I effort will evaluate and demonstrate a beam combination scheme for the kilowatt system. In particular, novel fiber-cladding geometry will be thoroughly studied. With the Phase I funding, a system will be constructed that not only could inject 320W power into a laser fiber, it will also demonstrate the capability and potential for kilowatt power levels. A solid foundation for further development will be provided by a successful Phase I program. The proposed technology will also benefit diode pumped solid-state lasers, high power laser beam transmission, airborne laser and other applications. Anticipated Benefits/Commercial Applications: High power, high efficiency fiber lasers have been sought for long time. The applications for high power fiber lasers are numerous both for the military and the commercial sectors. The applications include communication, medicine, laser cutting, pumping other lasers, and a host of other scientific research areas.

Keywords:
Laser diode array, Laser beam combination, Kilowatt Fiber laser, Diode laser coupling, Fiber cladding, Diffraction limited beam

We propose to develop a kilowatt fiber laser that is highly efficient at the conversion of electrical power into a diffraction-limited laser beam. The overall goal of this program is to deliver an unprecedented kilowatt-class fiber laser. The laser will be compact in size and light in weight. The goals of the Phase I are all accomplished or exceeded ahead of time. The feasibility of the proposed fiber laser is fully demonstrated. The newly developed beam shaping technology showed the capability to inject kilowatt or even multi-kilowatt pumping power into small laser fiber aperture. In particular, novel fiber-cladding geometry were thoroughly studied, showing the high-efficiency and feasibility for high-power operation.. A fiber laser device was also made for commercial laser fiber evaluation. A solid foundation for further development has been provided by the successful Phase I program. In Phase II, a prototype fiber laser with ~1kW CW power will be constructed based on the outstanding results of Phase I. The record-breaking fiber laser will have the following characteristics: 1. Fiber laser output power ~1 kW 2. Operation mode: CW 3. Beam quality M2 factor <1.1 4. Center wavelength : 1.09?Ìm Anticipated Benefits/Commercial Applications: The applications of high power, high efficiency fiber lasers include communication, medicine, laser cutting, pumping other lasers, and a host of other scientific research areas.

Keywords:
Fiber laser,, diode pumped fiber laser, Yb-doped fiber, kilowatt laser, solid state laser, FL, DPSSL