Patent ID: 11966043
Assignee: CANON KABUSHIKI KAISHA
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 1:
2. An exposure apparatus for exposing a substrate while scanning a mask and the substrate, the exposure apparatus comprising:
a projection optical system including:
a first plane surface;
a first concave surface;
a convex surface;
a second concave surface;
a second plane surface; and
a plurality of adjusters configured to adjust a shape of each of the first concave surface and the second concave surface by applying a force to a rear surface of each of the first concave surface and the second concave surface,

wherein the projection optical system is configured to:
project a pattern of the mask onto the substrate; and
cause light transmitted through the pattern of the mask to be reflected by the first plane surface, the first concave surface, the convex surface, the second concave surface, and the second plane surface, in this order,

wherein, in a state where corrections points are obtained by projecting force acting points of the plurality of adjusters on the first concave surface and the second concave surface in a direction parallel to an optical axis of the convex surface, the force acting points are set so that, among a first ray in a light flux emitted from a first point on the mask and a second ray in the light flux emitted from a second point on the mask different from the first point, and respectively reflected by the first concave surface and the second concave surface:
the first ray strikes the correction points of the first concave surface but does not strike the correction points of the second concave surface; and
the second ray does not strike the correction points of the first concave surface but strikes the correction points of the second concave surface, and

wherein the force acting points are set so that the correction points of the second concave surface are arranged at one of:
positions shifted from the correction points of the first concave surface in a radial direction centered on the optical axis; or
positions shifted from the correction points of the first concave surface in a circumferential direction centered on the optical axis.