Abstract: A magnifying imaging optical system is disclosed that has precisely three mirrors, which image an object field in an object plane into an image field in an image plane. A ratio between a transverse dimension of the image field and a transverse dimension measured in the same direction of a useful face of the last mirror before the image field is greater than 3. In a further aspect, the magnifying imaging optical system is disclosed that has at least three mirrors, which image an object field in an object plane in an image field in an image plane. A first mirror in the beam path after the object field is concave, a second mirror is also concave and a third mirror is convex. An angle of incidence of imaging beams on the last mirror before the image field is less than 15°.

Abstract: An optical system is described herein which has a compact, all reflective design that has multiple fields of view for imaging an object. The optical system also has identical viewing directions and can have several different configurations for adding laser range finding and designating components.

Abstract: In general, in a first aspect, the invention features a system that includes a microlithography projection optical system. The microlithography projection optical system includes a plurality of elements arranged so that during operation the plurality of elements image radiation at a wavelength ? from an object plane to an image plane. At least one of the elements is a reflective element that has a rotationally-asymmetric surface positioned in a path of the radiation. The rotationally-asymmetric surface deviates from a rotationally-symmetric reference surface by a distance of about ? or more at one or more locations of the rotationally-asymmetric surface.

Abstract: An optical apparatus has a primary optical element having a primary spherical optical surface with a primary center of curvature, wherein the primary spherical optical surface has a peripheral portion that extends outside a usable aperture of the optical apparatus, and a secondary optical element. A mount suspends the secondary optical element spaced apart from the primary optical element, wherein the mount comprises a number of leg sections, each leg section extending between the primary and secondary optical elements. Each leg section terminates in a spherical mating surface that rests against the peripheral portion of the primary optical element. The spherical mating surface has a mating surface center of curvature that is substantially concentric with the primary center of curvature.

Abstract: A planar light source device is provided which has high light extraction efficiency and in which a change in color tone at different viewing angles is small. The planar light source device includes, on a light emitting surface, a concavo-convex structure layer made of a resin composition. In this planar light source device, the concavo-convex structure layer has a cone, pyramid, or prism shape, and the resin composition contains a transparent resin and particles. In particular, in the planar light source device, variations in any of x- and y-chromaticity coordinates in any directions in a hemisphere on the light emitting surface are within ±0.1, the diameter of the particle is 10 ?m or less, and the amount of the particles is 1 to 40 wt % based on the total amount of the resin composition. In addition, the difference in refractive index between the particles and the transparent resin is 0.05 to 0.5.

Abstract: Optical system for a telescope having independent optical arms adapted to collect light rays over a first cross sectional area and compress it into a second cross sectional area less than the first cross sectional area. Orthogonal mirror pairs of parabolic trough mirrors compress light in first one dimension and then the other dimension and feed the light into a focusing smaller telescope structure. The gathered light is kept parallel and its wavefront is kept in phase, allowing the telescope to have the diffraction limit of the collective aperture. The optical arms are independently adjustable to point the system toward different objects of interest and track them.

Abstract: A wide-field-of-view (WFOV) optical system includes a negative optical-power primary mirror configured to receive and reflect light from an image scene; a low optical-power secondary mirror configured to receive and reflect light from the primary mirror; a negative optical-power tertiary mirror configured to receive and reflect light from the secondary mirror; and a positive optical-power quaternary mirror configured to receive and reflect light from the tertiary mirror. The primary, secondary, tertiary and quaternary mirrors are configured to maintain an effective focal length (EFL) at edges of the field of view (FOV) of the optical system to be at least equal to a center of the FOV of the optical system so that a spatial resolution of the optical system essentially remains constant across the FOV.

Abstract: The disclosure generally relates to imaging optical systems that include a plurality of mirrors, which image an object field lying in an object plane in an image field lying in an image plane, where at least one of the mirrors has a through-hole for imaging light to pass through. The disclosure also generally relates to projection exposure installations that include such imaging optical systems, methods of using such projection exposure installations, and components made by such methods.

Abstract: Described are new magnifying apparatus based on two dimensional arrays of micro magnifying modules (MMMs) positioned along a plane perpendicular to the axis of the MMMs. In addition, the structure may include a two dimensional array of micro beam multipliers (MBMs) to improve the quality of the image. The micro beam multipliers are positioned along a plane parallel to the array of micro magnifying modules. The array of micro magnifying modules, with or without the micro beam multipliers, may be constructed as a thin plate with a thickness of a few millimeters, through which the object is viewed. An object at a distance appears in the magnifying apparatus as a magnified image and the magnifying apparatus can be used for viewing an object at a distance in a way similar to the use of a conventional magnifier for viewing an object in a short distance.

Abstract: A catadioptric objective includes a plurality of optical elements arranged along an optical axis to image a pattern from an object field in an object surface of the objective to an image field in an image surface region of the objective at an image-side numerical aperture NA with electromagnetic radiation from a wavelength band around a central wavelength ?<300 nm. The optical elements include a concave mirror and a plurality of lenses. The projection objective forms an image of the pattern in a respective Petzval surface for each wavelength ? of a wavelength band, the Petzval surfaces deviating from each other for different wavelengths. The plurality of lenses include lenses made from different materials having substantially different Abbe numbers.

Abstract: In general, in one aspect, the invention features an objective arranged to image radiation from an object plane to an image plane, including a plurality of elements arranged to direct the radiation from the object plane to the image plane, wherein the objective has an image side numerical aperture of more than 0.55 and a maximum image side field dimension of more than 1 mm, and the objective is a catoptric objective.

Abstract: A lens for a light emitting diode is formed with a material having a refractive index of n, and the lens includes a base, a first curved circumferential surface extending from the base, a curved center-edge surface extending from the first curved circumferential surface, and a curved centermost surface extending from the curved center-edge surface. The base includes a groove for receiving a light emitting chip therein. In the lens, a distance from a center of the base to a point of the curved center-edge surface is always shorter than the radius of curvature for the point of the curved center-edge surface. The curved centermost surface has a concave shape with respect to the base.

Abstract: A reduction projection objective for projection lithography has a plurality of optical elements configured to image an effective object field arranged in an object surface of the projection objective into an effective image field arranged in an image surface of the projection objective at a reducing magnification ratio |?|<1. The optical elements form a dry objective adapted with regard to aberrations to a gaseous medium with refractive index n?<1.01 filling an image space of finite thickness between an exit surface of the projection objective and the image surface. The optical elements include a largest lens having a maximum lens diameter Dmax and are configured to provide an image-side numerical aperture NA<1 in an effective image field having a maximum image field height Y?. With COMP=Dmax/(Y?·(NA/n?)2) the condition COMP<15.8 holds.

Abstract: An optical system is described herein which has a compact, all reflective design that has multiple fields of view for imaging an object. The optical system also has identical viewing directions and can have several different configurations for adding laser range finding and designating components.

Abstract: A projection optics for microlithography, which images an object field in an object plane into an image field in an image plane, where the projection optics include at least one curved mirror and including at least one refractive subunit, as well as related systems, components, methods and products prepared by such methods, are disclosed.

Abstract: An optical system includes a primary mirror of a positive-powered concave substantially paraboloidal configuration configured to reflect light incident thereupon; a secondary mirror of a negative-powered convex hyperboloidal configuration facing the primary mirror configured to receive the light reflected from the primary mirror and redirect the light reflected from the primary mirror; a positive-powered tertiary mirror configured to substantially reimage and reflect divergent light rays incident from the secondary mirror; and a powered quaternary mirror configured to receive the reimaged light rays from the tertiary mirror, and to relay the received reimaged light rays to a focal point.

Abstract: An objective for imaging specimens is disclosed. The objective receives light energy from a light energy source configured to provide light energy in a wavelength range of approximately 480 to 660 nanometers, employs a Mangin mirror arrangement in conjunction with an immersion liquid to provide a numerical aperture in excess of 1.0 and a field size in excess of 0.05 millimeters, where every element in the objective has a diameter of less than approximately 40 millimeters.

Abstract: An imaging system. An array of light sources and an array of lenses corresponding to the light sources and having optical axes substantially parallel to one another are provided. The lenses produce collimated output beams. An afocal optical relay having an optical axis substantially parallel to the optical axes of the lenses is also included, the array of lenses being positioned relative to the afocal optical relay so as to form an optical system that produces an image of each collimated output beam on an image plane, each image having a prescribed depth of focus and spot size. The light sources preferably are lasers producing an array of respective laser beams having high intensity and a long waist. A system for writing information on a light-sensitive label includes the imaging system. Methods of imaging and of writing information on a light-sensitive label are also provided.

Abstract: An afocal beam relay has a concave reflective surface having a first center of curvature and a first vertex that define an optical axis. A convex reflective surface has a second center of curvature that is substantially coincident with the first center of curvature and a second vertex that lies along the optical axis. The convex reflective surface faces toward the concave reflective surface to relay a decentered entrance pupil to a decentered exit pupil. An aspheric corrector element is disposed in the path of input light that is directed to the decentered entrance pupil and has correction values that are substantially centered on the first center of curvature.

Abstract: A laser light source device includes a laser light source that emits a laser beam as a fundamental wave and an optical wavelength conversion element that converts the fundamental wave into a second harmonic. An optical lens system including a first surface having positive power and a second surface having negative power is arranged between the laser light source and the optical wavelength conversion element. The first surface and the second surface are arranged in order from the laser light source side.

Abstract: A catadioptric objective includes a plurality of optical elements arranged along an optical axis to image a pattern from an object field in an object surface of the objective to an image field in an image surface region of the objective at an image-side numerical aperture NA with electromagnetic radiation from a wavelength band around a central wavelength ?. The optical elements include a concave mirror and a plurality of lenses. The projection objective forms an image of the pattern in a respective Petzval surface for each wavelength ? of a wavelength band, the Petzval surfaces deviating from each other for different wavelengths. In embodiments, a longitudinal departure p of the Petzval surface at a given wavelength from a planar reference surface at an edge field point of the image field (at maximum image height y?), measured parallel to the optical axis in the image surface region, varies with the wavelength ? according to dp/d?<(0.2?/NA2)/nm.

Abstract: An apparatus and method is provided, for combining two or more EUV (extreme ultra violet) sources for illumination of a reticle. According to the principles of the present invention two or more EUV sources are combined in a single illumination system, using multiple first mirror arrays, each of which is associated with a respective EUV source, and a single second mirror array defining a pupil, and configured to receive reflected EUV radiation from the plurality of first mirror arrays, and to illuminate the reticle. Preferably, the first mirror array associated with each EUV source has a fly's eye configuration, the single second mirror array has a fly's eye configuration, and a condenser is positioned between the single second mirror array and the reticle. The number of mirror elements in the second mirror array is equal to or greater than the total number of mirror elements in the first mirror array.

Abstract: The present invention relates to an optical imaging device, in particular for microscopy, with a first optical element group and a second optical element group, wherein the first optical element group and the second optical element group, on an image plane, form an image of an object point of an object plane via at least one imaging ray having an imaging ray path. The first optical element group comprises a first optical element with a reflective first optical surface in the imaging ray path and a second optical element with a reflective second optical surface in the imaging ray path, wherein the first optical surface is concave. The second optical element group comprises a third optical element with a concave reflective third optical surface in the imaging ray path and a fourth optical element with a convex reflective fourth optical surface in the imaging ray path without light passage aperture.

Abstract: A reduction projection objective for projection lithography has a plurality of optical elements configured to image an effective object field arranged in an object surface of the projection objective into an effective image field arranged in an image surface of the projection objective at a reducing magnification ratio |?|<1. The optical elements form a dry objective adapted with regard to aberrations to a gaseous medium with refractive index n?<1.01 filling an image space of finite thickness between an exit surface of the projection objective and the image surface. The optical elements include a largest lens having a maximum lens diameter Dmax and are configured to provide an image-side numerical aperture NA<1 in an effective image field having a maximum image field height Y?. With COMP=Dmax/(Y?·(NA/n?)2) the condition COMP<15.8 holds.

Abstract: Provided is a compact and bright imaging optical system having a high resolution. The imaging optical system includes three reflectors composed of a first reflector (1), a second reflector (2), and a third reflector (3) that are arranged in this order on an optical path of incident ray so as not to block the incident light. In the imaging optical system, in which light beams reflected by the three reflectors form an image plane (4), a convex mirror is used for any one of the first reflector (1) and the third reflector (3) and a concave mirror is used for the other thereof, and vertexes of a triangular dipyramid (6) are defined in terms of a central chief ray (5) by an appropriate point on the central chief ray (5) that is incident to the first reflection surface, a reflection point of each central chief ray on the first to third reflection surfaces, and an image forming point of the central chief ray.

Abstract: In general, in a first aspect, the invention features a system that includes a microlithography projection optical system. The microlithography projection optical system includes a plurality of elements arranged so that during operation the plurality of elements image radiation at a wavelength ? from an object plane to an image plane. At least one of the elements is a reflective element that has a rotationally-asymmetric surface positioned in a path of the radiation. The rotationally-asymmetric surface deviates from a rotationally-symmetric reference surface by a distance of about ? or more at one or more locations of the rotationally-asymmetric surface.

Abstract: An all-reflecting, non-relayed optical system having an aperture stop and an optical axis and configured to provide images of objects. The system includes a positive power primary mirror configured to receive radiation from the objects, a negative power secondary mirror configured to receive the radiation reflected from the primary mirror and a positive power tertiary mirror configured to receive the radiation reflected from the secondary mirror. The system further includes a focal plane configured to receive the radiation reflected from the tertiary mirror and to form an image of the objects. The aperture stop of the optical system is located between the tertiary mirror and the image plane. Accordingly, the image plane may be cold shielded to prevent or reduce radiation reflected from the optical elements that interferes with the desired image.

Abstract: Optical system for a telescope having independent optical arms adapted to collect light rays over a first cross sectional area and compress it into a second cross sectional area less than the first cross sectional area. Orthogonal mirror pairs of parabolic trough mirrors compress light in first one dimension and then the other dimension and feed the light into a focusing smaller telescope structure. The gathered light is kept parallel and its wavefront is kept in phase, allowing the telescope to have the diffraction limit of the collective aperture. The optical arms are independently adjustable to point the system toward different objects of interest and track them.

Abstract: An optical sheet includes a substrate onto which light is incident, and a convex part protruded from the substrate by a predetermined thickness. A thickness of the convex part increases from an edge to a center thereof.

Abstract: A method comprises computing an interference pattern between a simulated design input optical signal and a simulated design output optical signal, and computationally deriving an arrangement of at least one diffractive element set from the computed interference pattern. The interference pattern is computed in a transmission grating region, with the input and output optical signals each propagating through the transmission grating region as substantially unconfined optical beams. The arrangement of diffractive element set is computationally derived so that when the diffractive element set thus arranged is formed in or on a transmission grating, each diffractive element set would route, between corresponding input and output optical ports, a corresponding diffracted portion of an input optical signal incident on and transmitted by the transmission grating. The method can further comprise forming the set of diffractive elements in or on the transmission grating according to the derived arrangement.

Abstract: A beam shaping telescope includes two mirrors having rotationally symmetric curvature inclined to the optical axis of the telescope. By selecting an appropriate curvature, spacing, and inclination of the mirrors, the telescope can be used to transform an astigmatic laser beam having a non-circular cross section into a circular beam having essentially zero astigmatism.

Abstract: A Schiefspiegler telescope with three reflecting surfaces, preferably for observing the earth from space, particularly for imaging radiometers. A novel possibility for realizing a reflector telescope without vignetting which permits a simple construction and a simple adjustment of the reflecting surfaces relative to one another. In a Schiefspiegler telescope with three reflecting surfaces whose mirror axes are arranged within a plane, the primary reflecting surface and tertiary reflecting surface are convex surfaces of identical shape arranged symmetrically with respect to an axis of symmetry. The secondary reflecting surface is arranged symmetric to the primary reflecting surface and tertiary reflecting surface so as to be rotationally symmetric around the axis of symmetry so that all three reflecting surfaces have an axially symmetric mirror arrangement with respect to design in which the optical imaging is transmitted to a receiver in the manner of an off-axis telescope.

Abstract: There is a need for providing a projection optical system that is appropriate for maintaining high resolution with low distortion, miniaturizing a reflector, decreasing the number of reflectors, and decreasing the depth and the bottom (or top) of a display used for a rear projection television, for example. The projection optical system according to the invention enlarges and projects images from a primary image surface existing at a reducing side to a secondary image surface existing at an enlarging side. The projection optical system has a first optical system L11 and a second optical system L12. The first optical system L11 forms an intermediate image (position II) of the primary image surface. The second optical system L12 has a concave reflector AM1 that forms the secondary image surface resulting from the intermediate image. A light beam travels from the center of the primary image surface and to the center of the secondary image surface and crosses an optical axis.

Abstract: High-resolution imaging systems are provided. In one embodiment, an imaging system based on a Cassegrain or Schmidt-Cassegrain objective, with coaxial primary and secondary mirrors, is provided with a microdisplacement mechanism acting on the secondary mirror to displace the image on a focusing array. In another embodiment, two co-axial Cassegrain-type objectives are provided one within the other with a common focal plane array, which therefore detects combined wide field-of-view and narrow field-of-view images.

Abstract: A system for inspecting a specimen is provided. The system includes an illumination subsystem configured to produce a plurality of channels of light energy, each channel of light energy produced having differing characteristics (type, wavelength, etc.) from at least one other channel of light energy. Optics are configured to receive the plurality of channels of light energy and combine them into a spatially separated combined light energy beam and direct it toward the specimen. A data acquisition subsystem comprising at least one detector is provided, configured to separate reflected light energy into a plurality of received channels corresponding to the plurality of channels of light energy and detect the received channels.

Abstract: A digital still camera switches an image sensor between moving picture shooting and still picture shooting. The digital still camera includes a variable-magnification optical system having a plurality of lens groups of which four are movable. At least one of the movable lens groups travels different movement trails for magnification variation between during zooming in moving picture shooting and during zooming in still picture shooting.

Abstract: A virtual input element image projection apparatus couples a suitable lens and an optical element to increase the diverging angle of a virtual input element image or generate a plurality of portions of the virtual input element image that are coupled to form the complete virtual input element image without reducing diffraction efficiency. The projection distance for generating the virtual input element image may also be shortened.

Abstract: High-resolution imaging systems are provided. In one embodiment, an imaging system based on a Cassegrain or Schmidt-Cassegrain objective, with coaxial primary and secondary mirrors, is provided with a microdisplacement mechanism acting on the secondary mirror to displace the image on a focusing array. In another embodiment, two co-axial Cassegrain-type objectives are provided one within the other with a common focal plane array, which therefore detects combined wide field-of-view and narrow field-of-view images.

Abstract: A design for inspecting specimens, such as photomasks, for unwanted particles and features such as pattern defects is provided. The system provides no central obscuration, an external pupil for aperturing and Fourier filtering, and relatively relaxed manufacturing tolerances, and is suited for both broad-band bright-field and laser dark field imaging and inspection at wavelengths below 365 nm. In many instances, the lenses used may be fashioned or fabricated using a single material. Multiple embodiments of the objective lensing arrangement are disclosed, all including at least one small fold mirror and a Mangin mirror. The system is implemented off axis such that the returning second image is displaced laterally from the first image so that the lateral separation permits optical receipt and manipulation of each image separately.

Abstract: A method comprises computing an interference pattern between a simulated design input optical signal and a simulated design output optical signal, and computationally deriving an arrangement of at least one diffractive element set from the computed interference pattern. The interference pattern is computed in a transmission grating region, with the input and output optical signals each propagating through the transmission grating region as substantially unconfined optical beams. The arrangement of diffractive element set is computationally derived so that when the diffractive element set thus arranged is formed in or on a transmission grating, each diffractive element set would route, between corresponding input and output optical ports, a corresponding diffracted portion of an input optical signal incident on and transmitted by the transmission grating. The method can further comprise forming the set of diffractive elements in or on the transmission grating according to the derived arrangement.

Abstract: A projection objective provides a light path for a light bundle from an object field in an object plane to an image field in an image plane. The projection objective includes a first mirror (S1), a second mirror (S2), a third mirror (S3), a fourth mirror (S4), a fifth mirror (S5), a sixth mirror (S6), a seventh mirror (S7), and an eighth mirror (S8). The light bundles includes light with a wavelength in a range of 10-30 nm. The light is provided via the eight mirrors, and in the light path exactly one intermediate image of the object field is provided.

Abstract: A photolithography reduction projection catadioptric objective includes a first optical group including an even number of at least four mirrors, and a second at least substantially dioptric optical group more imageward than the first optical group including a number of lenses for providing image reduction. The first optical group provides compensative axial color correction for the second optical group.

Abstract: A catadioptric objective includes a plurality of optical elements arranged along an optical axis to image a pattern from an object field in an object surface of the objective to an image field in an image surface region of the objective at an image-side numerical aperture NA with electromagnetic radiation from a wavelength band around a central wavelength ?. The optical elements include a concave mirror and a plurality of lenses. The projection objective forms an image of the pattern in a respective Petzval surface for each wavelength ? of a wavelength band, the Petzval surfaces deviating from each other for different wavelengths. In embodiments, a longitudinal departure p of the Petzval surface at a given wavelength from a planar reference surface at an edge field point of the image field (at maximum image height y?), measured parallel to the optical axis in the image surface region, varies with the wavelength ? according to dp/d?<(0.2?/NA2)/nm.

Abstract: High-resolution imaging systems are provided. In one embodiment, an imaging system based on a Cassegrain or Schmidt-Cassegrain objective, with coaxial primary and secondary mirrors, is provided with a microdisplacement mechanism acting on the secondary mirror to displace the image on a focusing array. In another embodiment, two co-axial Cassegrain-type objectives are provided one within the other with a common focal plane array, which therefore detects combined wide field-of-view and narrow field-of-view images.

Abstract: There is provided a projection optical system for projecting a pattern on an object surface onto an image surface in a reduced size. The projection optical system comprising six reflective surfaces that include, in order of reflecting light from the object surface, a first reflective surface, a second convex reflective surface, a third convex reflective surface, a fourth reflective surface, a fifth reflective surface and a sixth reflective surface, and an aperture stop along an optical path between the first and second reflective surfaces. And the following condition is met, where L1 is an interval between the object surface and the surface apex that is the closest to the object surface, and L2 is an interval between the surface apex of the first reflective surface and the surface apex that is the closest to the object surface: 0.75 < L ? ? 1 L ? ? 2 < 1.25 .

Abstract: A catadioptric projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective comprises: a first objective part for imaging the pattern provided in the object plane into a first intermediate image; a second objective part for imaging the first intermediate imaging into a second intermediate image; a third objective part for imaging the second intermediate imaging directly onto the image plane; wherein a first concave mirror having a first continuous mirror surface and at least one second concave mirror having a second continuous mirror surface are arranged upstream of the second intermediate image; pupil surfaces are formed between the object plane and the first intermediate image, between the first and the second intermediate image and between the second intermediate image and the image plane; and all concave mirrors are arranged optically remote from a pupil surface.

Abstract: A printer controller for an inkjet printer comprises a purpose-specific microprocessor; connections for linking the microprocessor to an external USB module, a printhead, a paper transport mechanism and a print media sensor; a memory module; a power source connection and an authentication chip. The microprocessor represents an integrated circuit fabricated on a single substrate. The integrated circuit includes a data bus and purpose-specific functional units connected to the data bus. The functional units include a JPEG decoder, a compressed bi-level expander, a halftoner, and a printhead interface. A general-purpose processor may also be connected to the data bus for controlling the functional units. The processor may be connected to run software that coordinates the functional units to receive, expand and print pages.

Abstract: A catadioptric projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective comprises: a first objective part for imaging the pattern provided in the object plane into a first intermediate image; a second objective part for imaging the first intermediate imaging into a second intermediate image; a third objective part for imaging the second intermediate imaging directly onto the image plane; wherein a first concave mirror having a first continuous mirror surface and at least one second concave mirror having a second continuous mirror surface are arranged upstream of the second intermediate image; pupil surfaces are formed between the object plane and the first intermediate image, between the first and the second intermediate image and between the second intermediate image and the image plane; and all concave mirrors are arranged optically remote from a pupil surface.

Abstract: A high resolution objective lens assembly (20, 120, 220, 320) is implemented with refractive lens elements made of modified fused silica for operation at deep ultraviolet (DUV) wavelengths to reduce birefringence-caused image aberrations. The high resolution is achieved by an optical design that is characterized by a very high numerical aperture (NA) and short wavelength operation.

Abstract: A projection lens for imaging a pattern arranged in an object plane onto an image plane using electromagnetic radiation from the extreme-ultraviolet (EUV) spectral region has several imaging mirrors between its object plane and image plane that define an optical axis of the projection lens and have reflective coatings. At least one of those mirrors has a graded reflective coating that has a film-thickness gradient that is rotationally symmetric with respect to a coating axis, where that coating axis is acentrically arranged with respect to the optical axis of the projection lens. Providing at least one acentric, graded, reflective coating allows designing projection lenses that allow highly uniform field illumination, combined with high total transmittance.