Title:
PROJECTION OPTICAL SYSTEM, EXPOSURE DEVICE AND METHOD OF MANUFACTURING ARTICLE
Document Type and Number:
Japanese Patent JP2021092684
Kind Code:
A
Abstract:
To provide a projection optical system advantageous in reducing asymmetrical aberrations.SOLUTION: A projection optical system is configured to pass luminous flux from an object plane obj through a first concave reflection surface M1, a convex reflection surface M2, a second concave reflection surface M3 having a different radius of curvature from the first concave reflection surface M1, and a refraction surface Lp having positive refracting power in order to form an image on an image plane img, wherein the radius R of curvature of the convex reflection surface M2, the image formation magnitude β of the whole projection optical system, and the distance from the convex reflection surface M2 to the second concave reflection surface M3 are properly set.SELECTED DRAWING: Figure 2
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Inventors:
OSAKA NOBORU
SUZUKI KANJI
KONO MICHIO
SUZUKI KANJI
KONO MICHIO
Application Number:
JP2019223747A
Publication Date:
June 17, 2021
Filing Date:
December 11, 2019
Export Citation:
Assignee:
CANON KK
International Classes:
G02B17/08; G02B13/18; G02B13/24; G03F7/20
Attorney, Agent or Firm:
Takuma Abe
Sogo Kuroiwa
Sogo Kuroiwa