| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical element having a periodical structure with a smaller period than the wavelength of the light used and having higher performance than a conventional one. <P>SOLUTION: The optical element is obtained by layering a structural body having a smaller periodical structure than the wavelength of the light used, and the element is controlled to satisfy conditions to obtain desired phase difference at least two wavelengths in the wavelength region to be used. <P>COPYRIGHT: (C)2004,JPO |
