| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical element which compensates unevenness of illuminance distribution by using optical characteristics of an illumination system in spite of not having transmittance distribution that directly complements intensity distribution of a light source and which has an advantage also in terms of processing and design. <P>SOLUTION: An illuminance equalizing optical element is characterized in that adjacent grooves each of which has broader width than a wavelength of utilized light wave, are arranged at an interval broader than the wavelength on at least one optical surface and the grooves exclude a part or all of incident light beams from an optical path by refractive index difference. <P>COPYRIGHT: (C)2008,JPO&INPIT |
