Abstract: Conventional retroreflection mirrors in the form of right angle prisms are quite sensitive to beam position and beam angle errors. Manufacturing and assembly tolerances are also a cause of concern in conventional devices. Accordingly, the present invention solves these aforementioned problems by providing a retroreflection device comprising: a beam director, preferably in the form of a Wollaston prism; a polarization rotator, preferably in the form of a quarter wave plate; and a flat reflective surface, such as a plane mirror. The device of the present invention is far less sensitive to beam angle alignment and is completely independent of the beam position. The present invention is particularly useful as a beam splitter for directing orthogonally polarized beams of light back along parallel paths in an interleaver apparatus.

Abstract: Conventional retroreflection mirrors in the form of right angle prisms are quite sensitive to beam position and beam angle errors. Manufacturing and assembly tolerances are also a cause of concern in conventional devices. Accordingly, the present invention solves these aforementioned problems by providing a retroreflection device comprising: a beam director, preferably in the form of a Wollaston prism; a polarization rotator, preferably in the form of a quarter wave plate; and a flat reflective surface, such as a plane mirror. The device of the present invention is far less sensitive to beam angle alignment and is completely independent of the beam position. The present invention is particularly useful as a beam splitter for directing orthogonally polarized beams of light back along parallel paths in an interleaver apparatus.

Abstract: An apparatus capable of operating as an interleaver, a deinterleaver, a filter, or some combination thereof is described. An optical device that can be configured to multiple different optical components. In one embodiment, the optical device can be configured to operate as a single double-pass interlayer/deinterleaver, as two single-pass interleaver/deinterleavers, or as one or more filters. In one embodiment, the optical device has ports on two or more planes and a birefringent element that occupies the two or more planes. Connections between the two or more planes can be made by walk-off crystals internal to the optical device or between ports by connections that are external to the optical device to configure the optical device.