Two-grating coupler with deflection for optical waveguide - produces output beam with corrected phase or direction from intensity distribution in parallel or inclined plane

摘要

The optical waveguide (1) is formed on a pref. plane-parallel glass plate (6) which has a second grating (3) on the opposite face. The light from a laser diode (5) emitting into the waveguide (1) is diffracted from the first grating (2) into the plate (6), and from the second grating (3) into free space (4) at an angle (alpha). The first grating (2) produces a defined intensity distribution and the second (3) corrects its phase or direction. ADVANTAGE - Can be mfd. by available technology for higher coupling efficiency and ample scope for matching to necessary beam and waveguide geometries.