Optical element having a dielectric multilayer film

摘要

In an optical element having an optical substrate and a laminate having high-refractive-index and low-refractive-index layers laid on top of one another, the low-refractive-index layers are formed of a mixture of Al₂O₃ and SiO₂. Alternatively, in an optical element having an optical substrate and a laminate having high-refractive-index and low-refractive-index layers laid on top of one another, the low-refractive-index layers are formed of a mixture of SiO₂ and a material having a refractive index approximately equal to the refractive index of SiO₂ and having a property of mitigating compression stresses in SiO₂, and the high-refractive-index layers are formed of a material based on titanium oxide.