Catadioptric projection optical system and exposure apparatus having the same
AssigneeCanon Kabushiki Kaisha
InventorsTakashi Kato, Chiaki Terasawa
Life of this patent
Estimating the term…
Abstract
A catadioptric projection optical system for forming plural intermediate images of a first object and for imaging the image of the first object onto a second object, said catadioptric projection optical system includes at least one concave mirror, a first deflective reflector, and a second deflective reflector, wherein a light reflected by the first deflective reflector is directly led to the second deflective reflector.
Claims26
A catadioptric projection optical system for forming plural intermediate images of a first object and for imaging the image of the first object onto a second object, said catadioptric projection optical system comprising:
- a concave mirror;
- a first flat mirror;
- and
- a second flat mirror,
- wherein a light reflected by the first flat mirror is directly led to the second flat mirror.
A catadioptric projection optical system for forming plural intermediate images of a first object and for imaging the image of the first object onto a second object, said catadioptric projection optical system comprising:
- a concave mirror;
- a first deflective reflector;
- and
- a second deflective reflector,
- wherein only optical elements having a refractive power of 0 are provided in an optical path between the first deflective reflector and the second deflective reflector.
A catadioptric projection optical system as a triple imaging system for forming an intermediate image of a first object twice and for imaging the image of the first object onto a second object, said catadioptric projection optical system comprising, in order from the first object:
- a first lens unit that does not form a reciprocating optical system that an incidence light and reflected light pass;
- a catadioptric unit that forms the reciprocating optical system;
- and
- a second lens unit that does not form the reciprocating optical system,
- wherein said catadioptric unit includes:
- a third lens unit;
- and
- a concave mirror opposing to the first object,
- wherein said third lens unit includes, in order from the first object:
- a fourth lens unit having a positive refractive power;
- and
- a fifth lens unit having a negative refractive power,
- wherein said catadioptric projection optical system further comprising a first deflective reflector and a second deflective reflector are provided between the concave mirror and the second lens unit.
A catadioptric projection optical system for forming plural intermediate images of a first object and for imaging the image of the first object onto a second object, said catadioptric projection optical system comprising:
- a concave mirror;
- a first deflective reflector;
- a second deflective reflector;
- wherein only an optical element having a refractive power of 0 is provided in an optical path between the first deflective reflector and the second deflective reflector.
Dependencies are inferred from the claim text.