Optimization of Lightguide Coupling Grating for Single Incidence Direction

Coupling of light into a lightguide is of major interest for various applications in modern optics. In VirtualLab Fusion, with the Fourier modal method (FMM, also known as RCWA) and parametric optimization tools, one can optimize the real grating geometries so to achieve best coupling efficiencies for specific diffraction orders. This example shows the design strategy for optimizing a rectangular grating for one specific incidence direction to obtain the optimum lightguide coupling efficiency.