| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To improve the coupling efficiency of light by minimizing the influence of the boundary part of regions in a polarization independent optical isolator of a type in which incident light beams pass through a plurality of birefringent elements respectively arranged in two parallel regions. <P>SOLUTION: The polarization independent optical isolator of a diffraction interference type is arranged between a first and second optical fibers having a condensing function at distal ends, so that the incident beam diameter of light to an isolator element is expanded to make an area projected in the overlapped optical axis direction of a region boundary part of the region boundary part ignorably smaller than the area of a beam area. Thus, the polarization independent optical isolator of satisfactory optical characteristic is provided. <P>COPYRIGHT: (C)2003,JPO</p> |
