| 摘要 |
PURPOSE:To obtain clear interference fringes, by inputting converging luminous flux through a beam splitter into an optical fiber loop under the good conditions, and differentiating the starting points of diverging luminous flux outputted from the optical fiber loop at the same time. CONSTITUTION:A beam splitter 3' and a semitransparent mirror 3R' are exclusively used either for P polarization or S polarization. For example, when laser light is linearly polarized light and the direction of polarization is in parallel with the surface of paper, the product is exclusively used for the P polarization. When the direction is perpendicular to the surface of the paper, the product is exclusively used for the S polarization. Interference fringes 7B are obtained by limiting the unnecessary luminous flux. The fringes have the fringe pattern of concentric circles because two starting points are located on the same lines and the diverging luminous fluxes, whose distances from an interference plane 7 are different, are interfered. The interference fringes 7B show a clear fringe pattern, because the luminous fluxes, which are outputted from end surfaces A and B of an optical fiber loop 6 and reach the interference plane 7, are larger than the luminous fluxes, which are reflected by the same end surfaces and reach the interference plane 7. |
