A novel design for beam forming grating couplers

Summary Edge-emitting laser diodes need astigmatic lenses for collimating and focusing the laser beam. The integration of the element on chip offers a more elegant solution. A grating is etched into the cladding of the planar waveguide. Beam forming can be achieved by modulating the grating parameters or by using a tapered cladding. These two possibilities are discussed in this paper.