| 摘要 |
<P>PROBLEM TO BE SOLVED: To facilitate manufacture while suppressing a scattering in an adhesively laminated diffractive optical element. <P>SOLUTION: The diffractive optical element 1 includes a first optical member 10 which has a first diffraction grating 14 with a sawtooth cross section and a second optical member 11 which has a second diffraction grating 15 with the sawtooth cross section and is different from the first optical member 10 in a refractive index. In the diffractive optical element 1, the first and second optical members 10 and 11 are laminated with the first and second diffraction gratings 14 and 15 closely adhered. A center line average roughness Ra_a of a diffraction surface 14c of the diffraction grating 14 is set in a predetermined range. <P>COPYRIGHT: (C)2012,JPO&INPIT |
