发明名称 |
Optical information medium and a method of manufacturing the medium. |
摘要 |
An optical information medium (20) for recording, such as DVR-blue, and a method for manufacturing such a medium (20) is provided. Reading from and recording onto the medium (20) is performed by means of a focused radiation beam (10) having a radiation wavelength » and a numerical aperture NA. Said medium has a substrate (1), and a stack (2) of layers provided thereon. The stack (2) comprises at least a first recording stack (3) and k radiation beam transmissive layers (4, 5). Each transmissive layer (4, 5) has a refractive index n i and an average thickness d i µm and 1 ‰ i ‰ k and k ‰¥ 2. The thickness d k of layer k (5) is determined by a simple formula which depends on the parameters n i for i = 1...k and d i for i = 1...k-1. Such a medium (20) has zero or substantially zero spherical aberration at the focal point, being at the recording layer of the first recording stack (3), of said radiation beam (10). |
申请公布号 |
ZA200207649(B) |
申请公布日期 |
2003.09.23 |
申请号 |
ZA20020007649 |
申请日期 |
2002.09.23 |
申请人 |
KONINKLIJKE PHILIPS ELECTRONICS N.V. |
发明人 |
HENDRIKS, BERNARDS, H. W. |
分类号 |
G11B7/2403;G11B7/24038;G11B7/24067;G11B7/243;G11B7/254;G11B7/2542;G11B7/257;G11B7/258;G11B7/2585;G11B7/26 |
主分类号 |
G11B7/2403 |
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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