US Patent 7924505 Free-space hitlessly switchable optical interleaver

A reflective surface and a beamsplitting surface are optically coupled to a mirror and to phase optics arranged in interleaver configuration so as to either reflect all light to a single output in an all-pass mode of operation, or to split the incoming beam and produce odd and even channel outputs in an interleaver mode of operation. The direction of the incoming beam is switched hitlessly between the reflective and beamsplitting surfaces by passing the incoming beam through a transparent slab coupled to a rotating mechanism.