| 摘要 |
PURPOSE:To facilitate manufacture and reduce optical coupling loss by arranging a uniaxial birefrigent crystal plate between a lens and an optical fiber having no polarization dependency, and adjusting the position relation between a single polarization optical fiber and the lens in the optical axis direction. CONSTITUTION:Linear polarized light which is projected from an optical fiber 1 and has an electric field vector perpendicular to this paper surface is transmitted through the lens 4 as shown by solid lines and coupled with an optical fiber 3 without being changed in angle by the birefringent crystal plate 5. On the other hand, linear polarized light which is projected from an optical fiber 2 and has an electric field vector parallel to the paper surface is passed through the lens 4 as shown by broken lines and coupled with the optical fiber 3 after being changed in angle by the birefringent crystal plate 5. Then when the interval (d) between the optical fibers 1 and 2 or the thickness (t) of the birefringent crystal plate 5 deviates from a set value, the position relation between the optical fibers 1 and 2 and lens 4 is deviated from a set value to vary the image conversion rate of the lens 4, thus correcting the deviation. Thus, the manufacture is facilitated and the coupling loss is reduced. |
