Design of high efficiency odd-port beam splitters

In this paper, we propose a novel design for odd-port beam splitters which are constructed using only a single-layer high-density binary grating. The properties of this grating are investigated theoretically by a simplified modal method and demonstrated by experimental results. The diffraction efficiency over 85% can be achieved while the uniformity can still be maintained at less than 1%. The effect of deviations from the design parameters on the performance of the grating is also presented.