Patent ID: 6339661
Filing Date: 2002-01-15
Classification: G02B,G02F

Abstract:
An inline polarization maintaining optical circulator for at least three optical fibers comprising:a birefringent wedge set having first and second birefringent wedges, wherein said first birefringent wedge has an optical axis disposed at 45Â° to the optical axis of the second birefringent wedge and perpendicular to the light propagation direction, with the bases of the birefringent wedges being oppositely disposed; a nonreciprocal 45Â° polarization rotating film disposed between said first and second birefringent wedges; a first polarization maintaining optical fiber forming a first port, said fiber being disposed on a first side of said birefringent wedge set, and having its slow axis aligned with the optical axis of the first birefringent wedge; a second polarization maintaining optical fiber forming a second port, said fiber being disposed on a second side of said birefringent wedge set, having its slow axis aligned with the optical axis of the second birefringent wedge; a third polarization maintaining optical fiber forming a third port, said fiber being disposed on the first side of said birefringent wedge set, said having its slow axis aligned perpendicular to the optical axis of the first polarization maintaining optical fiber; and said birefringent wedge set and said nonreciprocal 45Â° polarization rotating film splitting a light beam originating from said first optical fiber into first and second beams, and thereafter recombining said first and second beams such that they are parallel and collinear with each other and directing said recombined beam into the second optical fiber; said birefringent wedge set and said nonreciprocal 45Â° polarization rotating film splitting a light beam originating from said second output fiber into first and second beams, and thereafter directing said split beams at an angle such that one of said beams will impinge upon the third optical fiber.