An all-reflective or reflective and cata-dioptric optical system includes 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 on-axis four mirror anastigmat telescope includes an entrance pupil configured to receive light from an image, and a mirror assembly. The mirror assembly has a first reflective surface having a central aperture formed therein, a second reflective surface, a third reflective surface having a central aperture formed therein, a fourth reflective surface, and an aperture stop. The mirror assembly is configured to receive light from the image on a common axis and to reflect the light successively by the four coaxial reflective surfaces through the aperture stop. The telescope further comprises a detector configured to receive light from the mirror assembly. The central aperture formed in the first reflective surface defines a field stop to limit the field of view.

A multi channel beamsplitter system operating over a wide spectral band has high optical performance despite the fact that the incoming and/or exiting light is not collimated and its material is dispersive. This is achieved using wavefront compensators that are matched to the curvature of the wavefronts of the incoming and/or exiting light.

A method includes measuring properties of a three-dimensional topography of a lithographic patterning device, the patterning device including a pattern and being constructed and arranged to produce a pattern in a cross section of a projection beam of radiation in a lithographic projection system, calculating wavefront phase effects resulting from the measured properties, incorporating the calculated wavefront phase effects into a lithographic model of the lithographic projection system, and determining, based on the lithographic model incorporating the calculated wavefront phase effects, parameters for use in an imaging operation using the lithographic projection system.

An optical system to divide a light flux from an object plane includes a first curved-surface mirror, and second, third, and fourth reflecting portions. The second reflecting portion divides and reflects light flux from the first curved-surface mirror to respective different positions on the first curved-surface mirror as first light fluxes. The third reflecting portion reflects, as third light fluxes, the first light fluxes. The fourth reflecting portion reflects the third light fluxes from the third reflecting portion. A number of reflective surfaces of each of the third and fourth reflecting portions on which the first and third light fluxes are incident is the same as a division number in the dividing of the light flux into the second light fluxes. The first and third light fluxes are reflected by the respective third and fourth reflecting portions to be image-formed so that divided images of the object plane are formed.

A device for optically imaging at least a part of an object, the device having an optical axis and including a two-dimensional first array of first microlenses, having a first side intended to face the object, and a second side, opposite the first side, a two-dimensional second array of second microlenses, each first microlens being aligned with a second microlens on an axis parallel to the optical axis, wherein each first microlens comprises a first catoptric system, and preferably a first catadioptric system.

An optical lithography system is provided, comprising: a polygonal structure having a central region and a central axis; an UV light source detachably disposed in the central region or at an end of the polygonal structure; a light parallelizer positioned in the polygonal structure for creating substantially parallel light rays from the UV light source exiting the polygonal structure before reaching a lithography target adjacent to an exit of the polygonal structure, which includes at least three mirrors arranged such that the first mirror receives incident light from the UV light source and reflects thereof from the first mirror towards the second mirror, the second mirror receiving the reflected light as a second incident light and reflecting thereof from the second mirror towards the third mirror to create a spiral light path from the UV light source to the lithography target with substantially parallel light incident on the lithography target.

An optical lithography system is provided, comprising: a polygonal structure having a central region and a central axis; an UV light source detachably disposed in the central region or at an end of the polygonal structure; a light parallelizer positioned in the polygonal structure for creating substantially parallel light rays from the UV light source exiting the polygonal structure before reaching a lithography target adjacent to an exit of the polygonal structure, which includes at least three mirrors arranged such that the first mirror receives incident light from the UV light source and reflects thereof from the first mirror towards the second mirror, the second mirror receiving the reflected light as a second incident light and reflecting thereof from the second mirror towards the third mirror to create a spiral light path from the UV light source to the lithography target with substantially parallel light incident on the lithography target.

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 on-axis four mirror anastigmat telescope includes an entrance pupil configured to receive light from an image, and a mirror assembly. The mirror assembly has a first reflective surface having a central aperture formed therein, a second reflective surface, a third reflective surface having a central aperture formed therein, a fourth reflective surface, and an aperture stop. The mirror assembly is configured to receive light from the image on a common axis and to reflect the light successively by the four coaxial reflective surfaces through the aperture stop. The telescope further comprises a detector configured to receive light from the mirror assembly. The central aperture formed in the first reflective surface defines a field stop to limit the field of view.