发明名称 |
POLARIZING DIFFRACTION ELEMENT AND OPTICAL HEAD DEVICE |
摘要 |
<p>A polarizing diffraction element having a wavelength selectivity which functions as a polarizing diffraction element at a wavelength » 1 , and which does not function as a diffraction grating not depending on incident polarization state and shows high transmittance at a wavelength » 2 , and an optical head device employing the element, are provided. The polarizing diffraction element selectively diffracts or transmits incident light having two different wavelengths each containing a first circularly polarized light and a second circularly polarized light having a rotation opposite from the rotation of the first circularly polarized light, depending on wavelength and polarization state of the incident light. Then, a reflective wavelength region for at least the first circularly incident light, does not contain said two incident wavelengths.</p> |
申请公布号 |
EP1698917(A1) |
申请公布日期 |
2006.09.06 |
申请号 |
EP20040807907 |
申请日期 |
2004.12.27 |
申请人 |
ASAHI GLASS COMPANY, LIMITED |
发明人 |
OOI, YOSHIHARU;SATO, HIROMASA;GUNJIMA, TOMOKI |
分类号 |
G11B7/135;G11B7/1353;G02B5/30;G02B5/18;G11B7/125;G11B7/1275 |
主分类号 |
G11B7/135 |
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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