摘要 |
This invention provides a catadioptric optical system for achieving excellent imaging performance to obtain a resolution of quartermicron order. The catadioptric optical system is an optical system for transferring a reduced image of a pattern on a first plane onto a second plane and includes a beam splitter, an input lens group for guiding a light beam having a predetermined wavelength from the first plane to the beam splitter, an output lens group for guiding the light beam from the beam splitter to the second plane, a first concave mirror having an enlargement magnification, and a second concave mirror having a reduction magnification. The first concave mirror is arranged in an optical path of the light beam incident from the input lens group on the beam splitter and passing through the beam splitter to cause the passing light beam to be incident on the beam splitter again. The second concave mirror is arranged in an optical path of the light beam incident from the first concave mirror on the beam splitter and reflected by a beam splitter plane in the beam splitter and causes the reflected light beam to be incident on the beam splitter again.
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