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Disclosed is a projection optical system having relatively large image-side numerical aperture and projection field and being excellent in mechanical stability in respect of vibrations, and the like. The projection optical system includes a first image-forming optical system for forming a first inte

Disclosed is a projection optical system having relatively large image-side numerical aperture and projection field and being excellent in mechanical stability in respect of vibrations, and the like. The projection optical system includes a first image-forming optical system for forming a first intermediate image of a first surface (R), a second image-forming optical system having a concave reflective mirror and for forming a second intermediate image based on a radiation beam from the first intermediate image, and a third image-forming optical system for forming a final image on a second surface based on a radiation beam from the second intermediate image. Then, predetermined conditional expressions are satisfied with regard to a clear aperture diameter of the concave reflective mirror, a distance (L) between the first surface and the second surface, and a distance (H) between the concave reflective mirror and a reference optical axis.

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1. A projection optical system for forming an image of a first surface onto a second surface, comprising:a first image-forming optical system for forming a first intermediate image of the first surface, the first image-forming optical system being arranged in an optical path between the first surfac

1. A projection optical system for forming an image of a first surface onto a second surface, comprising:a first image-forming optical system for forming a first intermediate image of the first surface, the first image-forming optical system being arranged in an optical path between the first surface and the second surface; a second image-forming optical system including at least one concave reflective mirror and for forming a second intermediate image based on a radiation beam from the first intermediate image, the second image-forming optical system being arranged in an optical path between the first image-forming optical system and the second surface; and a third image-forming optical system for forming a final image onto the second surface based on a radiation beam from the second intermediate image, the third image-forming optical system being arranged in an optical path between the second image-forming optical system and the second surface, wherein a condition of: Ec/(Na×Ic)<10 is satisfied where a clear aperture diameter of the concave reflective mirror is Ec, an effective diameter of a projection field on the second surface is Ic, and an image-side numerical aperture of the projection optical system is Na. 2. The projection optical system according to claim 1, wherein a condition of: L/(Na×Ic)<63 is satisfied where a distance between the first surface and the second surface is L, the effective diameter of the projection field on the second surface is Ic, and the image-side numerical aperture of the projection optical system is Na.3. The projection optical system according to claim 2,wherein an optical axis of the first image-forming optical system and an optical axis of the third-image-forming optical system are set to virtually coincide with each other, and the projection optical system further comprises: a first deflection mirror arranged in an optical path between the first image-forming optical system and the second image-forming optical system; and a second deflection mirror arranged in an optical path between the second image-forming optical system and the third image-forming optical system. 4. The projection optical system according to claim 2, wherein a condition of: H/(Na×Ic)<15.5 is satisfied where a distance between a center of a reflective surface of the concave reflective mirror and the optical axis of the first image-forming optical system is H, the effective diameter of the projection field on the second surface is Ic, and the image-side numerical aperture of the projection optical system is Na.5. The projection optical system according to claim 1, wherein a condition of: H/(Na×Ic)<15.5 is satisfied where a distance between a center of a reflective surface of the concave reflective mirror and the optical axis of the first image-forming optical system is H, the effective diameter of the projection field on the second surface is Ic, and the image-side numerical aperture of the projection optical system is Na.6. The projection optical system according to claim 1,wherein an optical axis of the first image-forming optical system and an optical axis of the third-image-forming optical system are set to virtually coincide with each other, and the projection optical system further comprises: a first deflection mirror arranged in an optical path between the first image-forming optical system and the second image-forming optical system; and a second deflection mirror arranged in an optical path between the second image-forming optical system and the third image-forming optical system. 7. The projection optical system according to claim 1, wherein the projection optical system includes at least six aspheric optical surfaces.8. The projection optical system according to claim 1, wherein each of the first image-forming optical system, the second image-forming optical system and the third image-forming optical system includes at least one aspheric optical surface.9. A projection optical system for forming an image of a first surface onto a second surface, comprising:a first image-forming optical system for forming a first intermediate image of the first surface, the first image-forming optical system being arranged on an optical path between the first surface and the second surface; a second image-forming optical system including at least one concave reflective mirror and for forming a second intermediate image based on a radiation beam from the first intermediate image, the second image-forming optical system being arranged in an optical path between the first image-forming optical system and the second surface; and a third image-forming optical system for forming a final image onto the second surface based on a radiation beam from the second intermediate image, the third image-forming optical system being arranged in an optical path between the second image-forming optical system and the second surface, wherein a condition of: L/(Na×Ic)<63 is satisfied where a distance between the first surface and the second surface is L, an effective diameter of a projection field on the second surface is Ic, and an image-side numerical aperture of the projection optical system is Na. 10. The projection optical system according to claim 9,wherein an optical axis of the first image-forming optical system and an optical axis of the third-image forming optical system are set to virtually coincide with each other, and the projection optical system further comprises: a first deflection mirror arranged in an optical path between the first image-forming optical system and the second image-forming optical system; and a second deflection mirror arranged in an optical path between the second image-forming optical system and the third image-forming optical system. 11. The projection optical system according to claim 10, wherein a condition of: H/(Na×Ic)<15.5 is satisfied where a distance between a center of a reflective surface of the concave reflective mirror and the optical axis of the first image-forming optical system is H, the effective diameter of the projection field on the second surface is Ic, and the image-side numerical aperture of the projection optical system is Na.12. The projection optical system according to claim 9, wherein a condition of: H/(Na×Ic)<15.5 is satisfied where a distance between a center of a reflective surface of the concave reflective mirror and the optical axis of the first image-forming optical system is H, the effective diameter of the projection field on the second surface is Ic, and the image-side numerical aperture of the projection optical system is Na.13. The projection optical system according to claim 9, wherein the projection optical system includes at least six aspheric optical surfaces.14. The projection optical system according to claim 9, wherein each of the first image-forming optical system, the second image-forming optical system and the third image-forming optical system includes at least one aspheric optical surface.15. A projection optical system for forming an image of a first surface onto a second surface, comprising:a first image-forming optical system for forming a first intermediate image of the first surface, the first image-forming optical system being arranged in an optical path between the first surface and the second surface; a second image-forming optical system including at least one concave reflective mirror and for forming a second intermediate image based on a radiation beam from the first intermediate image, the second image-forming optical system being arranged in an optical path between the first image-forming optical system and the second surface; a third image-forming optical system for forming a final image onto the second surface based on a radiation beam from the second intermediate image, the third image-forming optical system being arranged in an optical path between the second image-forming optical system and the second surface; a first deflection mirror arranged in an optical path between the first image-forming optical system and the second image-forming optical system; and a second deflection mirror arranged in an optical path between the second image-forming optical system and the third image-forming optical system, wherein an optical axis of the first image-forming optical system and an optical axis of the third-image-forming optical system are set to virtually coincide with each other, and a condition of: H/Na×Ic)<15.5 is satisfied where a distance between a center of a reflective surface of the concave reflective mirror and the optical axis of the first image-forming optical system is H, an effective diameter of a projection field on the second surface is Ic, and an image-side numerical aperture of the projection optical system is Na. 16. The projection optical system according to claim 15, wherein the projection optical system includes at least six aspheric optical surfaces.17. The projection optical system according to claim 15, wherein each of the first image-forming optical system, the second image-forming optical system and the third image-forming optical system includes at least one aspheric optical surface.18. An exposure apparatus, comprising:an illumination system for illuminating a mask that is set on the first surface; and the projection optical system according to claim 1 for forming a pattern image, which is formed on the mask, onto a photosensitive substrate that is set on the second surface. 19. The exposure apparatus according to claim 18, wherein an effective exposure area on the photosensitive substrate is a rectangular area having a center separate from the optical axis of the third image-forming optical system by a predetermined distance.20. An exposure method, comprising the steps of:illuminating a mask that is set on the first surface; and projecting and exposing a pattern image, which is formed on the mask, through the projection optical system according to claim 1 onto a photosensitive substrate which is set on the second surface. 21. An exposure apparatus, comprising:an illumination system for illuminating a mask that is set on the first surface; and the projection optical system according to claim 9 for forming a pattern image, which is formed on the mask, onto a photosensitive substrate that is set on the second surface. 22. The exposure apparatus according to claim 21, wherein an effective exposure area on the photosensitive substrate is a rectangular area having a center separate from the optical axis of the third image-forming optical system by a predetermined distance.23. An exposure method, comprising the steps of:illuminating a mask that is set on the first surface; and projecting and exposing a pattern image, which is formed on the mask, through the projection optical system according to claim 9 onto a photosensitive substrate that is set on the second surface. 24. An exposure apparatus, comprising:an illumination system for illuminating a mask that is set on the first surface; and the projection optical system according to claim 15 for forming a pattern image, which is formed on the mask, onto a photosensitive substrate that is set on the second surface. 25. The exposure apparatus according to claim 24, wherein an effective exposure area on the photosensitive substrate is a rectangular area having a center separate from an optical axis of the third image-forming optical system by a predetermined distance.26. An exposure method, comprising the steps of:illuminating a mask that is set on the first surface; and projecting and exposing a pattern image, which is formed on the mask, through the projection optical system according to claim 15 onto a photosensitive substrate that is set on the second surface.