| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a cata catadioptric dioptric type projection optical system advantageously attaining higher NA, restraining the effective diameter of an optical element from getting very large and having excellent image forming performance. <P>SOLUTION: The catadioptric type projection optical system, which forms the intermediate image of a first object two or more times and forms the image on a second object, has first, second and third optical systems arranged on an optical axis in order from the first object. The second optical system includes at least two pairs of reflection surfaces, and is defined by an optical system between the reflection surface arranged at a position nearest to the first object and the reflection surface arranged at a position nearest to the second object out of the reflection surfaces constituting at least two pairs of reflection surfaces, and the intermediate image of a real image is not formed in an optical path between the two reflection surfaces constituting the pair of reflection surfaces. A sign of direction cosine to a scanning direction for the second object of the most off-axis principal ray made incident on the second optical system is the same as a sign of direction cosine to the scanning direction of the most off-axis principal ray exiting from the second optical system. <P>COPYRIGHT: (C)2009,JPO&INPIT |
