HIGH POWER SPATIAL FILTER

A high power laser diode pump module comprising a plurality of emitters outputting respective substantially parallel beams along a light path; a focusing lens impinged upon by and operative to converge the parallel beams at an angle range smaller than a reference value and corresponding to relatively low NA rays and at another angle range above the reference value and corresponding to relatively high NA rays; a channel structure defining a bounded inner central channel aligned with the focusing lens; and an optical multimode fiber mounted within the channel structure with an upstream end thereof being spaced downstream from an upstream end of the structure, so that the relatively high NA rays are reflected from a terminal surface of an upstream end of the channel structure, while the relatively low NA rays are coupled into a core of the fiber so as to excite a low number of modes.