| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an antireflection coating which has low reflectivity in three types of wavelength regions and is formed by two layers, an optical pickup component, an objective lens and a method for manufacturing optical pickup component. <P>SOLUTION: The antireflection coating is provided on the light transmission plane of an optical component of a refractive index n<SB>S</SB>used in an optical pickup unit that uses at least two wavelengths of about 405 nm and 655 nm. The antireflection coating comprises two layers being a high refractive index layer with a refractive index n<SB>H</SB>and optical film thickness n<SB>H</SB>d<SB>H</SB>formed on the optical component and a low refractive index layer with a refractive index n<SB>L</SB>and optical film thickness n<SB>L</SB>d<SB>L</SB>formed on the high refractive index layer, wherein reflectivity has a minimum value only at two places of about 405 nm and about 655 nm and has a maximum value at one place between the two minimum values. <P>COPYRIGHT: (C)2007,JPO&INPIT |
