| 摘要 |
PROBLEM TO BE SOLVED: To obtain a laminate type optical element not causing reflection on the interface between the glass substrate and a UV-curing resin layer by laminating a 1st layer of Al2 O3 and a 2nd layer of SiO2 each having a specified optical thickness between the substrate and the resin layer from the substrate toward the resin layer. SOLUTION: An Al2 O3 layer 3 having a refractive index of 1.65 and an optical thickness of λ/4 (λ is designed central wavelength) and an SiO2 layer 4 having a refractive index of 1.47 and an optical thickness of λ/2 are laminated between a glass substrate 1 having a refractive index of 1.75-1.95, e.g. 1.83 and a UV-curing resin layer 2 having a refractive index of 1.5 from the substrate 1 toward the resin layer 2. Harmful reflection due to the large difference between the refractive index of the substrate 1 and that of the resin layer 2 is suppressed and the objective optical element excellent in transmissivity is obtd. |
