| 摘要 |
An interference filter includes a pair of reflecting films, a first reflecting film and a second reflecting film, opposed to each other via a gap, the first reflecting film and the second reflecting film include an Ag-Sm-Cu alloy film or an Ag-Bi-Nd alloy film, the Ag-Sm-Cu alloy film includes Sm in an amount of 0.1 to 0.5 atomic %, and Cu in an amount of 0.1 to 0.5 atomic %, the sum of contents of Sm and Cu is equal to or lower than 1.0 atomic %, the Ag-Bi-Nd alloy film includes Bi in an amount of 0.1 to 3.0 atomic %, and Nd in an amount of 0.1 to 5.0 atomic %, and the thickness of the Ag-Sm-Cu alloy film or the Ag-Bi-Nd alloy film is 10 nm to 40 nm. |
