Patent ID: 8818148

Claim:
A ridge waveguide optical wavelength monitoring device that is part of a wavelength locker, the device comprising a ridge waveguide having a first mode conversion section, a second mode conversion section, and an intermediate section coupled between the first and second mode conversion sections, the first and second mode conversion sections being adapted to induce mode conversion between optical modes of light transmitted within the ridge waveguide, wherein the first mode conversion section has a first radius of curvature, the second mode conversion section has a second radius of curvature and the first and second radii of curvature are substantially equal, wherein an input section is coupled to the first mode conversion section at an end distal from the intermediate section and is adapted to substantially transmit a fundamental mode, and wherein an output section is coupled to the second mode conversion section at an end distal from the intermediate section and is adapted to substantially transmit the fundamental mode and a higher order mode.