Abstract: An interferometer system includes a rhomboid assembly having a first optical stack and a second optical stack mounted on the first stack. The first stack includes a first prism having an angled face mounted to an angled face of a second prism. The interface between these angled faces includes a first polarizing beam-splitter. The second stack includes a third prism having an angled face mounted to an angled face of the fourth prism. The interface between these angled faces includes a second polarizing beam-splitter. First, second, third, and fourth wave plate elements are located in beam paths between the rhomboid assembly and at least one of a measurement optic and a reference optic. A redirecting optic is located at least adjacent to the vertical faces of the first and the third prisms.

Abstract: A system and method are disclosed for providing movement to a person having a person center of gravity and a person moment. The system includes a receptacle configured to allow the person to adjust the person center of gravity, a counterweight for counterbalancing the person moment, a beam connecting the receptacle and the counterweight, a base for supporting the beam, a base joint connecting the base and the beam, configured to allow the beam to rotate with respect to the base joint; wherein an adjustment in the person center of gravity provides rotation of the beam.