Polarization-balanced beamsplitter

Claim 1

A polarization-balanced beamsplitter assembly for providing six polarization-balanced output beams from a single input light beam independent of the polarization state of the input light beam, wherein any polarization in said input beam is resolvable along an s-component axis and a p-component axis, wherein said s-component axis defines an s-component polarization and said p-component axis defines a p-component polarization, wherein said s-component axis is orthogonal to said p-component axis, the assembly comprising: thirteen beamsplitter cubes arranged to provide said six polarization-balanced output beams, each cube containing a partially reflective surface, wherein a light beam incident on said partially reflective surface is split into a transmitted light beam and a reflected light beam, wherein said transmitted light beam contains a first portion of said s-component polarization and a first portion of said p-component polarization, wherein said reflected light beam contains a second portion of said s-component polarization and a second portion of said p-component polarization, wherein each cube contains a plane of incidence defined by the incident light beam and the reflected light beam, wherein each of said six polarization-balanced output beams pass through two pairs of polarization-balanced beamsplitter cubes selected from said thirteen beamsplitter cubes, wherein each of said pairs of polarization-balanced beamsplitter cubes have orthogonal planes of incidence relative to the incident light beam, and wherein a light beam passing through each of said pairs of polarization-balanced beamsplitter cubes is either transmitted by both polarization-balanced beamsplitter cubes or reflected by both polarization-balanced beam splitter cubes.