US Patent 11646792 Optical communications terminal

An optical communications terminal including a polarizing element responsive to a first linearly polarized optical beam and rotating the first linearly polarized optical beam in a first linear direction, a beam separator responsive to and passing the first linearly polarized optical beam, and a circular polarizing element responsive to the first linearly polarized optical beam from the beam separator and circularly polarizing the first linearly polarized optical beam for transmission, where the circular polarizing element is switchable between two orthogonal switching states. The terminal receives a circularly polarized optical beam from another terminal and linearly polarizes the circularly polarized optical beam from the other terminal in a second linear direction that is orthogonal to the first linear direction and the beam separator directs the circularly polarized optical beam from the other terminal in a direction away from the polarizing element.