The invention concerns an optical beam-shaping system comprising: a first segment with parallel faces (L1) whereof the surfaces (10 and 11) are reflecting towards the segment inside such that various portions of the incident optical beam (F1) in a first input zone perform different numbers of reflection between the two faces and those various beam portions are offset in mutually parallel planes in first output zones; a second segment with parallel faces (L2) whereof the surfaces are likewise reflecting towards the segment inside such that on receiving in the second input zones the various beam portions transmitted by the first segment, said various portions perform different numbers of reflection between the two faces and are offset in second output zones, parallel to said planes so as to be aligned along a direction perpendicular to said planes. The invention is useful for coupling a laser source to an optical fibre.
