Projection optical system, exposure apparatus, and exposure method

摘要

An immersion projection optical system having, for example, a catadioptric and off-axis structure, reduces the portion of an image space filled with liquid (immersion liquid). The projection optical system, which projects a reduced image of a first plane onto a second plane through the liquid, includes a refractive optical element (Lp) arranged nearest to the second plane. The refractive optical element includes a light emitting surface (Lpb) shaped to be substantially symmetric with respect to two axial directions (XY-axes) perpendicular to each other on the second plane. The light emitting surface has a central axis (Lpba) that substantially coincides with a central axis (40a) of a circle (40) corresponding to a circumference of a light entering surface (Lpa) of the refractive optical element. The central axis of the light emitting surface is decentered in one of the two axial directions (Y-axis) from an optical axis (AX).

主权项

1. A projection optical system which projects an image of a first plane onto a second plane through a liquid, the projection optical system comprising:
a refractive optical element arranged nearest to the second plane; wherein the refractive optical element includes a light emitting surface shaped to be rotationally asymmetric with respect to an optical axis of the projection optical system based on a shape of an effective projection region formed on the second plane.