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Catadioptric optical system and exposure apparatus having the same

  • US 5,689,377 A
  • Filed: 04/05/1996
  • Issued: 11/18/1997
  • Est. Priority Date: 04/07/1995
  • Status: Expired due to Fees
First Claim
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1. A catadioptric optical system comprising:

  • a first imaging optical system forming an intermediate image of a pattern provided on a first surface, said first imaging optical system including a first lens group with a positive refracting power and a second lens group which includes a concave mirror having a concave surface facing said first surface, said second lens group having a negative lens component;

    a second imaging optical system forming an image of said intermediate image upon a second surface, a composite magnification of said first and second imaging optical systems being a reduction magnification; and

    a first optical path deflecting member disposed in an optical path from said first imaging optical system to said second imaging optical system so as to guide light from said first imaging optical system to said second imaging optical system,wherein a part of the first lens group of said first imaging optical system is positioned between said first optical path deflecting member and said second lens group, in a space through which both light directed from said first surface to said second lens group and light directed from said second lens group to said first optical path deflecting member pass, andwherein the first lens group includes, in the following order from said first surface toward said second lens group, a front lens group having a positive refracting power, an intermediate lens group having a negative refracting power, and a rear lens group having a positive refracting power.

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