Broadband transmission gratings with wide field of view based on efficient optimization of polynomial sidewall profiles

A new method for designing broadband transmission gratings with wide field of view for solar cell applications is proposed. The method is based on forming the sidewalls of the gratings according to polynomial functions. To achieve the optimal response, the roots of the polynomial are optimized. This method allows for generating complex sidewall profiles while keeping the number of variables at a manageable level. As an example a transmission filter for the visible band is designed that shows mean transmittance values of greater than 95% over the entire range for angles up to 60 degrees.