Design of all-dielectric three-wavelength non-polarizing parallel plate beam splitter

With the Needle thin film synthesis method and Conjugate graduate refinement method, all-dielectric three-wavelength non-polarizing parallel plate beam splitters are designed. The chosen of materials component and initial stack are based on Costich and Thelen’s theory. The results of design and analysis show that it maintains a very low polarization ratio in spectral range of (532±10), (633±10) and (1 315±10) nm. To the requirement for non-polarizing in 532, 633 and 1 315 nm, the reasonable angular field of design can be 45°±2°.