Coherent Broadband Fiber-Array Laser (CBFAL)

Compact, high power, 100 kW class plug-in efficient lasers, although difficult to develop, are critical for various applications. Existing solutions to this problem, based on coherent or incoherent combining of multiple fiber channels, have shown limited success. A new paradigm must be considered, encompassing both fundamental properties and practical results, to meet the challenging requirements of perfecting compact and high-power effective laser systems with high-quality output beam. An alternative solution to this problem is to couple the fiber channels inside a combined open cavity. Preliminary experimental data has demonstrated that this automatically solves the problem of mutual phase synchronization of the multiple channels. This proposal describes an innovative approach to developing a power-scalable fiber-array laser with a united output beam. The proposed method is inherently robust and auto-matches the spectral and polarization characteristics of individual channels. This should allow development of a laser system with an output power exceeding the multi-kW level. This Phase I effort includes design and analysis of a prototype system, along with laboratory measurements, to demonstrate concept feasibility. In addition, a commercialization strategy will be identified in order to market the system. During Phase II a prototype system will be built, tested, and demonstrated. BENEFIT: It is anticipated that the technology developed in this project will enable the construction of viable commercial high-power CW fiber array lasers. A scalable, high-power laser system composed of a variable number of phase-matched channels will find immediate application in industries such as high-precision laser cutting, welding and cleaning, commercial marking and packaging, medical and surgical applications, and remote sensing and free-space communications. Possible military applications include target acquisition, non-visible high brightness illuminators, ranging and tracking, and long-range missile interception. They can also be used to identify and track chemical and biological weapons of mass destruction.