Patent ID: 8121450
Filing Date: 2012-02-21
Classification: G02B

Abstract:
1. An arrangement for providing end-fire optical coupling between a free-space optical signal propagating along an optical axis and an optical waveguide incorporated within an optical substrate, the optical waveguide formed within a silicon surface layer of the optical substrate and the coupled light provided through an endface of the optical substrate, wherein the arrangement comprises: an optical waveguide disposed within the silicon surface layer such that an end portion thereof is pulled back by a predetermined distance from a vertical endface of said optical substrate; and a plasma-etched, optically smooth coupling facet formed along the vertical endface of the optical substrate for directing the free-spacing propagating optical signal into the optical substrate, the propagating optical signal thereafter being coupled into the end portion of the pulled back optical waveguide, the plasma-etched, optically smooth coupling facet also for re-directing reflected signals away from the optical axis.