| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical device which can maintain the optimum relative positions of two or more optical elements in a lens barrel, and a projection aligner with the device. SOLUTION: The optical system comprises two or more optical elements, reference mirrors, primary and secondary target mirrors that are arranged not changing their substantial relative positions to the primary and secondary optical elements in the plural of optical elements, primary and secondary measuring devices that measure the relative positions of the target mirrors to the reference mirrors, and a driving mechanism which drives at least one of the primary or secondary optical element so that their relative positions may have a specified relationship on the basis of the measurements of the primary and secondary measuring devices. COPYRIGHT: (C)2004,JPO&NCIPI |
