ANTIREFLECTIVE FILM AND OPTICAL ELEMENT HAVING THE SAME

• Main Author: CHIBA KOHEI
• Format: Patent
• Language: English; Japanese
• Published: 28.06.2018
• Subjects: OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

PROBLEM TO BE SOLVED: To provide an antireflective film which has an excellent productivity and presents a low reflectivity to base plates with various different indexes of refraction in a wide range of wavelength of a visible light.SOLUTION: The antireflective film has a structure in which first to sixth layers are deposited on a substrate in that order. The first layer is made of a high refractive index material with an optical film thickness of 0.045 λ to 0.971 λ, both inclusive, the second layer is made of a low refractive index material with an optical film thickness of 0.025 λ to 0.166 λ, both inclusive, the third layer is made of a high refractive index material with an optical film thickness of 0.038 λ to 0.375 λ, both inclusive, the fourth layer is made of a low refractive index material with an optical film thickness of 0.048 λ to 0.152 λ, both inclusive, the fifth layer is made of a high refractive index material with an optical film thickness of 0.045 λ to 0.119 λ, both inclusive, and the sixth layer is made of a super-low refractive index material with an optical film thickness of 0.228 λ to 0.331 λ, both inclusive, and with an index of refraction of 1.10 to 1.30, both inclusive.SELECTED DRAWING: Figure 1 【課題】生産性が良好で、種々の屈折率の基板に対して可視光の広い波長範囲において低反射の反射防止膜を提供する。【解決手段】基板上に、前記基板側から第１層、第２層、第３層、第４層、第５層、第６層までこの順に積層してなる反射防止膜であって、第１層の光学膜厚が０．０４５λ以上、０．９７１λ以下の高屈折率材料であり、前記第２層の光学膜厚が０．０２５λ以上、０．１６６λ以下の低屈折率材料であり、前記第３層の光学膜厚が０．０３８λ以上、０．３７５λ以下の高屈折率材料であり、前記第４層の光学膜厚が０．０４８λ以上、０．１５２λ以下の低屈折率材料であり、前記第５層の光学膜厚が０．０４５λ以上、０．１１９λ以下の高屈折率材料であり、前記第６層の光学膜厚が０．２２８λ以上、０．３３１λ以下で屈折率が１．１０以上、１．３０以下の超低屈折率材料であることを特徴とする構成とした。【選択図】図１