An integrated optical apparatus comprising a waveguide grating coupler with a flared waveguide portion

摘要

An integrated optical apparatus comprises a planar waveguide having an elongate guiding portion (104) and a grating coupler (102). The grating coupler (102) has at least a flared waveguide portion comprising a relatively narrow end portion and a relatively wide end portion, the flared portion having a grating positioned to couple light between the grating coupler (102) and an optical element. The grating comprises a plurality of curved elongate scattering elements (103) having curvatures defined by substantially elliptical paths so as to couple plane waves between the grating coupler (102) and the optical element.