Superprism effect with a large spatial dispersion and high efficiency in a reflection filter

Reflection-type thin film demultiplexers are interesting for optical communication, detection and some other fields. In this work a novel thin film reflection filter is proposed to obtain a large spatial dispersion with high efficiency. Based on the abnormal reflective phase change, the reflected beam will be shifted spatially as a function of wavelength. The numerical simulation of the distribution of reflected light is investigated by a transfer matrix, along with the Gaussian angular spectrum method. A thin film sample is fabricated and tested, and the experimental results found to be in good agreement with numerical simulation.