US 2,004,233,405 · Filed 2004-05-21

Projection optical system, exposure apparatus, and device manufacturing method

A projection optical system for projecting an image of a first object onto a second object includes a first imaging optical system that forms a first intermediate image of the first object, and includes a lens, a second imaging optical system that forms a second intermediate image of the first object, and includes a lens and a concave mirror, and a third imaging optical system that forms an image of the first object onto the second object, and includes a lens, wherein the first, second and third imaging optical systems are arranged along an optical path from the first object in this order, and 0.7<|β1·β2<<3.0 is met where β1 is a paraxial magnification of the first imaging optical system, and β2 is a paraxial magnification of the second imaging optical system.

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