| 摘要 |
PROBLEM TO BE SOLVED: To execute the assembly of a device and the adjustment of a mirror group highly accurately in a short time. SOLUTION: Inside a projection optical system lens barrel 20, a preceding stage mirror group (mirrors M1-M3) and a post stage mirror group (mirrors M4-M6) are incorporated in front and at the back of an intermediate image forming position P. The lens barrel 20 is divided into a preceding stage optical lens barrel 21 incorporating and housing the preceding stage mirror group and a post stage optical lens barrel 31 incorporating and housing the post stage mirror group, wave front aberration can be measured at the intermediate image forming position P and a space image can be formed as well. Thus, an optical performance is confirmed/adjusted in each mirror group. At the time, since the number of constituting mirrors of each mirror group is small, the mirror which is the cause of accuracy defect is easily searched. Then, after a sufficient performance is obtained in each mirror group, a projection optical system is assembled and the whole is adjusted. As a result, the device is assembled/adjusted efficiently in a short time. COPYRIGHT: (C)2004,JPO |
