| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve wavelength temperature characteristics and make an amount of change in extinction ratio smaller than ever before. <P>SOLUTION: An etalon filter comprises: first and second transparent members that are made of glass or crystal; and a hollow member that is provided between the first and second transparent members. The first transparent member comprises reflective films that are arranged on a surface facing the hollow member and on an opposite surface parallel to the surface, and the second transparent member comprises reflective films that are arranged on a surface facing the hollow member and on an opposite surface parallel to the surface. The first transparent member and the hollow member are bonded, and the second transparent member and the hollow member are bonded. When setting each thickness of the first and second transparent members as t and setting opening width of the hollow member as a, the etalon filter is configured to be represented by an expression, t/a≥0.3. <P>COPYRIGHT: (C)2013,JPO&INPIT |
