| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lighting optical device in which, when the device is mounted on an exposure system, the polarization level of an illumination light is varied in accordance with a pattern characteristic of a mask, thereby materializing an appropriate lighting condition. <P>SOLUTION: This device comprises a first polarizing prism (43aa) which is disposed in an optical path between a light source and an irradiating face and formed with a uniaxial crystal material, and which is configured to freely rotate a crystal optical axis about an optical axis of the lighting optical device with a wedged shape; a second polarizing prism (43ba) which is disposed in the optical path between the first polarizing prism and the irradiating face and formed with the uniaxial crystal material, and which is configured to freely rotate the crystal optical axis about the optical axis with the wedged shape; and a controller which controls to vary an angle formed between the crystal optical axis of the first polarizing prism and the crystal optical axis of the second polarizing prism, for setting the polarization level of a light which reaches the irradiating face to a given polarization level. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
