发明名称 |
Optical system for optical pickup device, coupling lens and optical information recording/reproducing apparatus |
摘要 |
An optical system includes an objective lens; and a plastic coupling lens to change a divergent angle of a light flux emitted from a light source and is structured such that the light flux emitted from the light source passes through both of the coupling lens and the objective lens when the light flux is converged onto an optical information recording medium and the reflected light flux reflected from the optical information recording medium passes through the objective lens without passing through the coupling lens when the reflected light flux is detected by a photo-detector. A ring-shaped diffractive structure is formed on at least one surface of the coupling lens and the diffractive structure generates an under-spherical aberration when a light flux having a longer wavelength comes in, and the coupling lens has a positive refractive power as a whole.
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申请公布号 |
US2003081528(A1) |
申请公布日期 |
2003.05.01 |
申请号 |
US20020261779 |
申请日期 |
2002.10.02 |
申请人 |
KONISHIROKU PHOTO IND |
发明人 |
SAITO SHINICHIRO |
分类号 |
G02B5/18;G02B13/00;G02B13/18;G11B7/125;G11B7/135;(IPC1-7):G11B7/00 |
主分类号 |
G02B5/18 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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