We introduce a novel technique allowing simultaneous combining and reshaping of several non-coherent laser sources. This Multi-Plane Light Conversion technique is based on a passive, tailored and multi-reflective phase element which realizes intrinsically lossless unitary transforms. This approach is particularly suitable for multiple kilowatt laser beam shaping applied to improved material processing. We present numerical and experimental results of 3 applications of this shaper: a multiple multi-mode laser beam shaper, a beam shaper and combiner for generating adaptive tailored beam, and a beam combiner managing up to ten incoherent laser beams with optimum output beam quality (M<sup>2</sup>). High power handling, up to 12 kW, of MPLC based shaper is also demonstrated.
Proc. SPIE. 9774, Next-Generation Optical Communication: Components, Sub-Systems, and Systems V
KEYWORDS: Digital signal processing, Modulation, Laser processing, Multiplexing, Single mode fibers, Telecommunications, Optical communications, Beam shaping, Local area networks, Multiplexers, Demultiplexers, Plutonium
Multi-Plane Light Conversion enables novel beam shaping devices, including spatial multiplexers. After a presentation of the achievable performances of these spatial multiplexers, which can combine 10 spatial modes with cross-talk below -22 dB and insertion loss below 4 dB, we review the performances of Multi-Plane Light Con-version in multiple application cases. These application cases include mode-multiplexed optical ampliﬁcation, high-power beam shaping and combining and LAN ﬁber capacity upgrade.
We report a six mode spatial multiplexer with high efficiency and high mode selectivity, based on the technique of Multi-Plane Light Conversion (MPLC). Using this mode selective multiplexer, we demonstrate a total insertion loss in a six-mode fiber below 5 dB and a mode-to-mode selectivity greater than 20 dB over a broad wavelength range from 1530 to 1565 nm. Furthermore, this device can address any spatial mode profile of any few-mode fiber with high fidelity. This mode-multiplexer proves to be fully compatible with a wavelength- and space-division multiplexed optical transmission line.