| 摘要 |
PURPOSE:To attenuate one of the two intrinsic modes propagating in the polarization plane maintaining fiber to form linearly polarized light and to eliminate losses and to improve reliability by removing a part of the clad of a polarization plane maintaining fiber and loading a metallic film thereon. CONSTITUTION:A part of the clad 14 of the polarization plane maintaining fiber 11 is removed in the direction parallel with the oscillating direction of the electric field of the one intrinsic mode of the two orthogonal intrinsic modes propagating in the polarization plane maintaining fiber 11 and the metallic film 12 is provided in this removed part. The intrinsic mode in which the electric field oscillates in the direction parallel with the film plane of the metallic film 12 of such polarizer 10 made of the optical fiber does not receive the attenuation by the metallic film 12. On the other hand, the intrinsic mode in which the electric field oscillates in parallel with the film plane of the metallic film 12 is attenuated by the metallic film 12. Only the mode in which the oscillation direction of the electric field is parallel with the film plane of the metallic film 12 of the two intrinsic modes propagating in the polarization plane maintaining fiber 11 is thereby passed and, therefore, the linearly polarized light is obtd. The losses are eliminated in this way and the reliability is enhanced. |
