An all-reflective optical system is described including a concave primary mirror having a central aperture and a radius, the primary mirror having one of a parabolic, non-parabolic conical, or aspherical surface, a convex secondary mirror facing the primary mirror, where an optical axis extends from a vertex of the primary mirror to a vertex of the secondary mirror, a concave tertiary mirror arranged behind the primary mirror, the tertiary mirror having one of a parabolic, non-parabolic conical or aspherical surface, a concave quaternary mirror arranged in the central aperture of the primary mirror or behind the primary mirror, the quaternary mirror having one of a spherical, parabolic, non-parabolic conical or aspherical surface, and at least one image plane having one or more aggregated sensors, wherein the image plane is positioned at a radial distance from the optical axis that is no more than the radius of the primary mirror.

An optical pulse stretcher includes a first delay optical system including a plurality of concave toroidal mirrors; and a beam splitter including a first surface and a second surface, causing a part of pulse laser light incident on the first surface to be transmitted in a first direction and output as a first beam and another part thereof to be reflected in a second direction and enter the first delay optical system, and causing a part of pulse laser light incident on the second surface from the first delay optical system to be reflected in the first direction and output as a second beam.

A projection exposure method for exposing a radiation-sensitive substrate with at least one image of a pattern of a mask is provided in which an illumination field of the mask is illuminated by illumination radiation with an operating wavelength λ that was provided by an illumination system.

There is provided a reflective image-forming optical system which is applicable to an exposure apparatus using, for example, EUV light and which is capable of increasing numerical aperture while enabling optical path separation of light fluxes. In a reflective imaging optical system (6) forming an image of a first plane (4) onto a second plane (7), the numerical aperture on a side of the second plane with respect to a first direction (X direction) on the second plane is greater than 1.1 times a numerical aperture on the side of the second plane with respect to a second direction (Y direction) crossing the first direction on the second plane. The reflecting imaging optical system has an aperture stop (AS) defining the numerical aperture on the side of the second plane, and the aperture stop has an elliptic-shaped opening of which size in a major axis direction (X direction) is greater than 1.1 times that in a minor axis direction (Y direction).

An all-reflective or reflective and cata-dioptric optical system is described including a concave primary mirror having a central aperture and a radius, the primary mirror having one of a parabolic, non-parabolic conical, or aspherical surface, a convex secondary mirror facing the primary mirror, the secondary mirror having an aspherical surface, where an optical axis extends from a vertex of the primary mirror to a vertex of the secondary mirror, a concave tertiary mirror arranged behind the primary mirror, the tertiary mirror having one of a parabolic, non-parabolic conical or aspherical surface, a concave quaternary mirror arranged in the central aperture of the primary mirror or behind the primary mirror, the quaternary mirror having one of a spherical, parabolic, non-parabolic conical or aspherical surface, and/or at least one image plane having one or more aggregated sensors. Additional multispectral imaging may utilize beam splitter(s), folding mirror(s), focal length optimizer(s) and/or additional image planes.

An illumination optical system is used with a reflective imaging optical system configured to form an image of a pattern arranged on a first plane onto a second plane, and is configured to illuminate an illumination area on the first plane with a light from a light source. The illumination optical system includes one or more reflecting mirrors configured to reflect the light from the light source to the first plane such that the reflected light reaches the first plane after crossing an optical path of a light which travels in the reflective imaging optical system.

An all-reflective optical system is described including a concave primary mirror having a central aperture and a radius, the primary mirror having one of a parabolic, non-parabolic conical, or aspherical surface, a convex secondary mirror facing the primary mirror, the secondary mirror having an aspherical surface, where an optical axis extends from a vertex of the primary mirror to a vertex of the secondary mirror, a concave tertiary mirror arranged behind the primary mirror, the tertiary mirror having one of a parabolic, non-parabolic conical or aspherical surface, a concave quaternary mirror arranged in the central aperture of the primary mirror or behind the primary mirror, the quaternary mirror having one of a spherical, parabolic, non-parabolic conical or aspherical surface, and at least one image plane having one or more aggregated sensors, wherein the image plane is positioned at a radial distance from the optical axis that is no more than the radius of the primary mirror.

An example optical system includes freeform mirrors configured to receive light from an object and to reflect the light among the freeform mirrors to produce an optical image of the object having positive distortion. The freeform mirrors include non-rotationally symmetric mirrors. The optical system also includes an along-track scanner having a line of imaging sensors configured to receive the optical image of the object from the freeform mirrors and to produce an image of the object having the positive distortion.

An imaging apparatus includes a first reflection optical system and a second reflection optical system having mutually different optical axes, each of the first and second reflection optical systems includes a plurality of reflecting surfaces, a first imaging portion configured to receive an imaging light reflected by the first reflection optical system, a second imaging portion configured to receive an imaging light reflected by the second reflection optical system, a first member, a second member, and a frame. A part of the plurality of reflecting surfaces of the first reflection optical system are reflecting surfaces provided on the frame. Among the plurality of reflecting surfaces of the first reflection optical system, a final-stage reflecting surface configured to reflect the imaging light toward the first imaging portion is a first reflecting surface formed on a surface of the first member.

An image offsetting apparatus for producing an offset image pathway and presenting the offset image pathway to an optic, including at least some of a mirror assembly wherein the mirror assembly comprises a first component mirror and a second component mirror, wherein the mirror assembly is attached or coupled so as to provide the offset image pathway that is offset from a direct image pathway between a target object and the optic.