Emitter array

An optical emitter device comprising:

• a plurality of point emitters arranged in an array comprising a plurality of rows of point emitters and a plurality of columns of point emitters, each of the plurality of point emitters comprising:
• a grating coupler configured to receive light along a transmission direction and to emit a respective beam of light in an emission direction;
• each grating coupler comprising:
• a first plurality of periodically spaced optical waveguide grating structures forming a directional grating for asymmetrically emitting light in the emission direction, at least some of the first plurality of periodically spaced optical waveguide grating structures including a notch, whereby a first portion of each of the first plurality of periodically spaced optical waveguide grating structures extends a different height than a second portion;
• and
• a second plurality of periodically spaced optical waveguide grating structures superposed over the first plurality of periodically spaced optical waveguide grating structures, the second plurality of periodically spaced optical waveguide grating structures spaced apart from the directional grating in the emission direction.