Daria, VincentRodrigo, Peter JGluckstad, Jesper2015-12-070030-4018http://hdl.handle.net/1885/20638We demonstrate a novel technique for generating tuneable complex field distributions for controllable coupling to high-order guided modes of micro-structured fibres. The optical Fourier transform of grating-based phase patterns, which are encoded on a computer-controlled spatial light modulator, generates complex field distributions for selective launching of a desired mode. Both the amplitude and the phase of the programmable fields are modulated by straightforward and fast adjustments of simple pre-defined binary phase-only diffractive patterns. Experiments demonstrate tuneable coupling to the second-order guided modes of a commercially available index-guiding silica fibre with a triangular lattice air-hole micro-structure.Keywords: Diffraction gratings; Fiber optics; Fourier transforms; Light modulation; Optical communication; Phase modulation; Fiber optic couplings; Micro-structured fibers; Optical fibers Diffraction and gratings; Fibre optic coupling; Phase modulation; Spatial light modulators200410.1016/j.optcom.2003.12.0752015-12-07