| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical filter and a package for an optical element, in which there is no variation in a refractive index, and from which desired optical characteristics can be obtained.SOLUTION: In an optical filter 1, an inorganic reflection film 3, an intermediate film 4 and a resin absorption film 5 are laminated on a transparent substrate 2 in this order, and thus, since the resin absorption film 5 is formed later than the inorganic reflection film 3 and intermediate film 4, production of moisture from the resin absorption film 5 can be suppressed, and variation in the refractive index of the inorganic reflection film 3 can be suppressed. When the refractive index of the inorganic reflection film 3 is defined as n1, and a refractive index of the resin absorption film is defined as n3, the intermediate film 4 has a refractive index n2 satisfying n1<n2<n3. By satisfying such the relation, reflection of light in an interface between the resin absorption film 5 and the intermediate film 4, and reflection of light in an interface between the intermediate film 4 and the inorganic reflection film 3 become small, and deterioration in transmittance of light in a visible light band can be prevented.SELECTED DRAWING: Figure 1 |
