Diode-Bar Side-Pumping of Double-Clad Fibers

摘要

Formatted diode bars are currently the preferred pump source for high-power fiber laser systems. Inrna formatted diode bar, the raw output of the diode bar is reformatted into a beam waist with arndivergence, aspect ratio, and fill factor suitable for coupling into a conventional multimode fiberrnpigtail. The main drawbacks to formatted diode bar pump sources are cost, complexity and anrninevitable tradeoff between coupling efficiency and source brightness. In this paper we describernhow the Embedded Mirror Side Pumping (EMSP) technique allows the raw output of anrnunformatted diode bar to be used directly for side pumping double clad fiber (DCF) amplifiers. ThernEMSP technique allows the raw output of an unformatted diode bar to be coupled directly into thernDCF inner cladding, without the same penalties in cost, complexity, coupling efficiency and loss ofrnbrightness. In particular, for applications at the 10 to 100 Watt power level and applications thatrnrequire arrays of DCF amplifiers, diode bar EMSP will provide a very attractive alternative tornsystems based on formatted diode bar pump sources.