Sliced grating coupler with increased beam alignment sensitivity

Abstract

Apparatus and methods relating to coupling radiation from an incident beam into a plurality of waveguides with a grating coupler are described. A grating coupler can have offset receiving regions and grating portions with offset periodicity to improve sensitivity of the grating coupler to misalignment of the incident beam.

1 . An integrated device comprising:
 a grating disposed on a substrate and arranged to couple radiation incident on the grating into a plurality of optical waveguides disposed on the substrate;   a first inlet to a first receiving region of the plurality of optical waveguides; and   a second inlet to a second receiving region of the plurality of optical waveguides, wherein the second inlet is offset a first amount with respect to the first inlet in a first direction approximately perpendicular to lines of the grating.   
     
     
         2 .- 20 . (canceled)