An optical surgical probe, configured to optically couple to a light source; comprising a light guide within a cannula, configured to receive a light beam from the light source and to emit the light beam at a distal end of the light guide; and a multi-spot generator at a distal end of the cannula, the multi-spot generator having a faceted proximal surface with oblique facets, configured to receive the light beam emitted at the distal end of the light guide and to split the received light beam into multiple beam-components, and a distal surface through which the multiple beam components exit the multi-spot generator, wherein the distal surface is micro structured with a modulation length smaller than a wavelength of the light beam in order to reduce the reflectance of light back into the probe.