POLARIZATION-INDEPENDENT BEAM SPLITTER

摘要

Disclosed is a polarization-independent beam splitter, comprising a substrate (1), wherein the substrate (1) is provided with a film system formed by alternately stacking a plurality of high-refractive-index film layers (2), middle-refractive-index film layers (3) and low-refractive-index film layers (4); and the material of the high-refractive-index film layer (2) is SiH, SiO _xH _y or a mixture of SiH and SiO_xH _y. The beam splitter can be applied to the fields of interferometers, imaging instruments, detection instruments, data centers, optical communication comb filters, etc., wherein there is a passband partially overlapping with at least a wavelength range of 800 nm to 4000 nm, and each SiH/SiO_xH _y layer has a refractive index of greater than 3 within the wavelength range of 800 nm to 4000 nm and an extinction coefficient of less than 0.0005 within the wavelength range of 800 nm to 4000 nm. The entire film system partially overlaps within the wavelength range of 800 nm to 4000 nm, and a low absorption and polarization independent beam splitter with various beam splitting ratios at large angles is realized.