Abstract: A microscope comprising a first turret bearing a plurality of lenses and a second turret bearing a plurality of filtering modules, the first turret and the second turret being borne on the same pivot and mounted to rotate, independently of each other, about this pivot, each lens of the first turret and each filtering module of the second turret being able to be arranged by rotation of the first turret and of the second turret into an active position of use in which a filtering module of the second turret is inserted into the optical path between a lens of the first turret and a detector.

Abstract: The invention proposed the catadioptric system, which consists of two main components: the first component comprising the two reflective mirrors, in which surface distortion of mirror 1 is parabolic, surface distortion of mirror 2 is aspheric; the second component is a relay consisting of three lenses: lens 1, lens 2, and lens 3 arranged after the medial image plane correspondingly; the second component helps reduce aberration to ensure receiving good quality image at a plane of the sensor.

Abstract: A Bi-spectral Korsch-type anastigmat telescope has an optical axis and a visible channel comprising a concave first mirror, a convex second mirror and a concave third mirror and a visible detector that is sensitive in a visible band, the mirrors being arranged so that the first mirror and the second mirror form, of an object at infinity, an intermediate image located between the second mirror and the third mirror, the third mirror forming, from this intermediate image, a final image in the visible focal plane of the telescope, wherein the visible detector is placed, an infrared channel comprising first and second mirrors in common with the visible channel, a third IR mirror, a fourth IR mirror, and an IR detector that is sensitive in an infrared band, the third and fourth IR mirrors being configured to form, from the intermediate image, a final image in an IR focal plane.

Abstract: An aerial camera system is disclosed that comprises at least one camera arranged to capture a plurality of successive images. Each camera including at least one respective image sensor, and the field of view of each camera is movable in a substantially transverse direction across a region of the ground. The system also includes a stabilisation assembly associated with each camera that has at least one steering mirror. The steering mirror is controllably movable so as to translate the optical axis of the camera relative to the at least one image sensor in synchronization with image capture, so as to effect stabilisation of an image on the at least one image sensor during image capture as the field of view of the camera moves in a substantially transverse direction across a region of the ground. The system is arranged to control the at least one camera to capture successive images at defined intervals as the field of view of the camera moves in a substantially transverse direction across a region of the ground.

Abstract: Certain example embodiments relate to electric, potentially-driven shades usable with insulating glass (IG) units, IG units including such shades, and/or associated methods. In such a unit, a dynamic shade is located between the substrates defining the IG unit, and is movable between retracted and extended positions. The dynamic shade includes on-glass layers including a transparent conductor and an insulator or dielectric film, as well as a shutter. The shutter includes a resilient polymer, a conductor, and optional ink. When the conductor is reflective, overcoat layers may be provided to help reduce internal reflection. The polymer may be capable of surviving high-temperature environments and may be colored in some instances. The polymer may be surface modified, e.g., to promote diffuse reflection, total internal reflection, etc.

Abstract: An optical system includes a first optical element including a first reflecting region having a convex shape toward an enlargement side, a second optical element having a reduction-side surface having a convex shape toward the enlargement side, and a third optical element having an enlargement-side surface having a convex shape toward the enlargement side, wherein the reduction-side surface of the second optical element or the enlargement-side surface of the third optical element includes a second reflecting region, wherein the third optical element includes a refracting region having positive power, and wherein light from the enlargement side proceeds to a reduction side sequentially through a refracting region of the first optical element, the second reflecting region, the first reflecting region, a refracting region of the second optical element, and the refracting region of the third optical element.

Abstract: A display device has a display, operable to generate a real image, and an optical system. In the optical system are at least two free-form reflective surfaces, S I and S2. At least one of the reflective surfaces is convex in one direction at substantially all points of its optically active area. Light rays from the display are reflected on SI before they are reflected on S2. The reflective surfaces SI and S2 are arranged to generate a virtual image from the real image on the display, by projecting light from the display to an eye position. The field of view occupied by the virtual image as seen from the eye position is greater than 50 degrees in at least one direction, preferably the direction linking the two eyes of an intended user.

Abstract: A surgical microscope is provided with a light receiving unit including at least a pixel having sensitivity to an infrared region, an imaging optical system which guides image light of an eye which is light reflected from the eye as an operation target to the light receiving unit, and a presentation unit which presents an image based on a sensor signal generated by the light receiving unit. The present technology is applicable to, for example, the surgical microscope used for an eye operation and the like.

Abstract: Optical systems that provide non-uniformity correction devices that are capable of providing low radiance level sources.

Abstract: A four-piece optical lens for capturing image and a five-piece optical module for capturing image are provided. In the order from an object side to an image side, the optical lens along the optical axis includes a first lens with positive refractive power; a second lens with refractive power; a third lens with refractive power; and a fourth lens with refractive power; and at least one of the image-side surface and object-side surface of each of the four lens elements are aspheric. The optical lens can increase aperture value and improve the imagining quality for use in compact cameras.

Abstract: A process for producing a reflective element for a mask blank, of which a reflective layer is hardly damaged at the time of etching treatment of an absorber layer. A process for producing a reflective element for a mask blank, which comprises (1) a step of forming a reflective layer on a first surface of a substrate, (2) a step of forming a first protective layer on the reflective layer, (3) a step of cleaning the substrate to form an exposed part of the reflective layer, which is not covered with the first protective layer, and (4) a step of forming a second protective layer on the first surface of the substrate to cover the exposed part of the reflective layer with the second protective layer.

Abstract: A non-relayed reflective triplet and a double-pass imaging spectrometer including the reflective triplet configured as its objective. In one example the reflective triplet includes a primary mirror that receives and reflects electromagnetic radiation from a viewed scene and defines an optical axis of the optical system, a secondary mirror that receives and reflects the electromagnetic radiation reflected from the primary mirror, and a tertiary mirror that receives the electromagnetic radiation reflected from the secondary mirror and focuses the electromagnetic radiation onto an image plane to form an image of the viewed scene. The primary, secondary, and tertiary mirrors together are configured to form a virtual exit pupil for the optical system, the image plane being located between the tertiary mirror and the virtual exit pupil. The reflective triplet is on-axis in aperture and off-axis in field of view.

Abstract: An image pickup device includes a first emission unit that emits a near infrared light toward a face of a driver from a front lower side of the driver, and a second emission unit that emits a near infrared light from an upper side of the driver. When a sunvisor is present at a storage position in which sunlight is not shielded, the second emission unit is disposed at a position to be covered with the sunvisor. A portion where the sunvisor present at a storage position covers the second emission unit is made of a material that shields a visible light contained in the sunlight and transmits the near infrared light.

Abstract: An optical sheet is formed by laminating, by co-extrusion molding, a first layer containing a polycarbonate resin, a second layer containing a polyamide resin, and a third layer, wherein the second layer is laminated between the first layer and the third layer, the first layer and second layer, and the second layer and third layer can each be peeled at the interface, and the outer surface of the first layer has a fine grooved structure. The optical sheet, which is provided with a plurality of layers in such a way, is capable of retaining, a sufficient amount of heat in a laminate in a mold since the entire sheet can be made thick during melt extrusion molding, and is able to improve the transferability of the fine grooved structure. In addition, the optical sheet can be made thinner by using only the peeled first layer as an optical sheet.

Abstract: A method of providing a catadioptric projection includes: providing a first partial objective for imaging an object field onto a first real intermediate image; providing a second partial objective for imaging the first real intermediate image onto a second real intermediate image, in which the second partial objective includes a concave mirror; providing a third partial objective for imaging the second intermediate image onto an image field, the third partial objective including an aperture stop; providing a first folding mirror and a second folding mirror; and providing an antireflection coating onto a surface of at least one lens that is directly adjacent to the concave mirror or that is separate from the concave mirror by a single lens, in which the antireflection coating is designed to have reflectivity of less than 0.2% for a wavelength between 150 nm and 250 nm and for an angle-of-incidence range between 0° and 30°.

Abstract: An optical system that images a scene at two different fields of view, with switching between fields of view enabled by switchable mirrored surface is disclosed. A voltage change across the switchable mirror element generates a change in the reflection and transmission properties of the element, such that the element switches between a mirror state and a lens state. When nested in an annular reflective optic system of a given field of view, the switching element enables the opening of an additional optical path through the center of the reflective optics where a set of refractive optics are assembled into an imaging system for a second field of view. This dual field-of-view system changes field of view with no mechanical movement.

Abstract: A system includes a plurality of sensors at distinct and separate locations, each of the distinct and separate locations being equidistant from a region that is configured to pass light that propagates along a beam path, the sensors being configured to sense radiation from an optical element positioned to interact with light that propagates on the beam path; and a controller including one or more electronic processors and a computer-readable medium, the computer-readable medium including instructions that, when executed, cause the one or more electronic processors to receive an output from each of the sensors, the output of each sensor including an indication of an intensity of the radiation detected by the sensor, and analyze the received output to determine a position of the light that propagates along the beam path.

Abstract: A projection objective configured to image an object field in an object plane into an image field in an image field plane includes a reflective unit, a first refractive unit, and a second refractive unit. An optical axis of the first refractive unit is parallel to but displaced from an optical axis of the second refractive unit. The reflective unit includes a first curved mirror and a second curved mirror. The second curved mirror is immediately downstream from the first curved mirror in a path of light from the object plane to the image plane. The projection objective is a microlithography projection objective.

Abstract: A projection objective for microlithography for imaging an object field onto an image field includes: a first partial objective for imaging the object field onto a first real intermediate image; a second partial objective for imaging the first intermediate image onto a second real intermediate image; a third partial objective for imaging the second intermediate image onto the image field, the third partial objective including an aperture; and a first folding mirror for deflecting radiation toward a concave mirror and a second folding mirror for deflecting the radiation from the concave mirror toward the image plane; in which the projection objective is an immersion projection objective in which during operation an immersion liquid is situated between a last lens surface and an image plane, and at least one surface of at least one lens in the second partial objective has an antireflection coating including at least six layers.

Abstract: A camera system includes an image sensor, a stop aperture, an infrared cut filter disposed between the image sensor and the stop aperture, and a lens assembly. The lens assembly has a field of view ranging between 80 degrees and 110 degrees and is disposed between the infrared cut filter on an image side of the lens assembly and the stop aperture on an object side of the lens assembly. The lens assembly includes six lenses. Four of the six lenses have positive optical power and two of the six lenses have negative optical power. The six lenses include first, second, third, fourth, fifth, and sixth lenses having first inline, second inline, third inline, fourth inline, fifth inline, and sixth inline relative positions, respectively, along an optical path through the lens assembly.

Abstract: A method for producing a reflective optical component for an EUV projection exposure apparatus, the component having a substrate having a base body, and a reflective layer arranged on the substrate, wherein the substrate has an optically operative microstructuring, comprises the following steps: working the microstructuring into the substrate, polishing the substrate after the microstructuring has been worked into the substrate, applying the reflective layer to the substrate. A reflective optical component for an EUV projection exposure apparatus correspondingly has a polished surface between the microstructuring and the reflective layer.

Abstract: A catadioptric projection objective has a multiplicity of lenses and at least one concave mirror, and also two deflection mirrors in order to separate a partial beam path running from the object field to the concave mirror from the partial beam path running from the concave mirror to the image field. The deflection mirrors are tilted relative to the optical axis of the projection objective about tilting axes running parallel to a first direction (x-direction). The first deflection mirror is arranged in optical proximity to a first field plane and the second deflection mirror is arranged in optical proximity to a second field plane, which is optically conjugate with respect to the first field plane. A displacement device for the synchronous displacement of the deflection mirrors is provided. The deflection mirrors have different local distributions of their reflection properties in first and second reflection regions, respectively.

Abstract: An off-axial three-mirror optical system with freeform surfaces includes an aperture, a primary mirror, a secondary mirror, a tertiary mirror, and a detector. The aperture is located on an incident light path. The primary mirror is located on an aperture transmitted light path. The secondary mirror is located on a primary mirror reflected light path. The tertiary mirror is located on a secondary mirror reflected light path. The detector located on a tertiary mirror reflected light path. A primary mirror surface and a tertiary mirror surface have a same freeform surface equation, and the freeform surface equation is a sixth order x?y? polynomial. A secondary mirror surface is a tenth order aspherical surface.

Abstract: A catadioptric projection objective has a multiplicity of lenses and at least one concave mirror, and also two deflection mirrors in order to separate a partial beam path running from the object field to the concave mirror from the partial beam path running from the concave mirror to the image field. The deflection mirrors are tilted relative to the optical axis of the projection objective about tilting axes running parallel to a first direction (x-direction). The first deflection mirror is arranged in optical proximity to a first field plane and the second deflection mirror is arranged in optical proximity to a second field plane, which is optically conjugate with respect to the first field plane. A displacement device for the synchronous displacement of the deflection mirrors is provided. The deflection mirrors have different local distributions of their reflection properties in first and second reflection regions, respectively.

Abstract: A multiple field-of-view telescope and optical sensor system and imaging methods using the system. In one example, an optical sensor system includes a primary imaging detector having a first field of view, a telescope configured to receive and focus electromagnetic radiation onto the primary imaging detector along a primary optical axis, a secondary detector having a second field of view different from the first field of view, and relay optics configured to direct and focus a portion of the electromagnetic radiation onto the secondary detector. In certain examples, the system further includes a fold mirror positioned to reflect the portion of the electromagnetic radiation to the relay optics.

Abstract: A system for producing thermal images acquires at least first and second thermal images comprising a plurality of pixels and a first and second dynamic range, respectively. The second dynamic range is such that its upper limit is higher than that of the first, and at least partially overlaps the first. A final thermal image is created comprising pixels from the first thermal image that are not saturated or nearly saturated with respect to the first dynamic range, and pixels from the second thermal image that are saturated or nearly saturated with respect to the first dynamic range. The resulting final image generally comprises both a large dynamic range and high signal-to-noise ratio.

Abstract: An optical imaging system and method in which a second channel is used to provide alignment data for achieving image frame stacking of image data in a first channel. In one example, image stacking of infrared images is achieved by obtaining and analyzing corresponding visible images to provide alignment data that is then used to align and stack the infrared images.

Abstract: An imaging optical system has a plurality of mirrors, which image an object field in an object plane into an image field in an image plane. A reflection face of at least one of the mirrors is configured as a free form face which cannot be described by a rotationally symmetrical function. The object field has an aspect ratio greater than 1. A ratio of a minimal and a maximal transverse dimension of the object field can be less than 0.9.

Abstract: A catadioptric projection optical system includes a plurality of lenses which are arranged between a first plane on which the pattern is arranged and a second plane on which the substrate is arranged. Two mirrors are arranged in an optical path of the light beam between the plurality of lenses and the second plane. A dioptric optical system is arranged in an optical path of the light beam between the two mirrors and the second plane the dioptric optical system forming the image of the pattern onto the second plane by the light beam from the two mirrors. The dioptric optical system includes a first negative lens and a second negative lens, the second negative lens being adjacent to the first negative lens along the single optical axis.

Abstract: A reflective minor includes a reflective film, a light-transmitting base and a light-transmitting adhesive layer. The reflective film includes a first connection surface and a plurality of reflection structures opposite to the first connection surface. Each reflection structure protrudes away from the first connection surface. The light-transmitting base includes a light penetration surface and a second connection surface opposite to the light penetration surface. The light-transmitting adhesive layer is disposed between the reflective film and the light-transmitting base and connected to the first connection surface and the second connection surface. An optical touch device is also provided in the present invention. Thus, the reflective minor as well as the optical touch device are easy to be manufactured and accordingly have a lower production cost.

Abstract: An objective optical system for ATR measurement is provided with a housing, in the interior, an ATR crystal that is transparent in visible light and has a semispherical surface through which light enters; an infrared optical member for irradiating a sample with infrared light at an angle that is equal to or greater than the critical angle; a visible light irradiation optical member which is disposed in the interior of the casing and which irradiates the sample with visible light from an angle less than the critical angle; and an observation optical member which is disposed on a position that is offset from the reflection angle relative to the angle at which the visible light enters the sample and which guides the scattering light from the sample to an observation device. As a consequence, it is possible to clearly observe the position of a sample subjected to ATR measurement.

Abstract: A three-mirror anastigmatic with at least one non-rotationally symmetric mirror is disclosed. The at least one non-rotationally symmetric mirror may be an electroformed mirror shell having a non-rotationally symmetric reflective surface formed by a correspondingly shaped mandrel.

Abstract: Catadioptric projection objective (1) for microlithography for imaging an object field (3) in an object plane (5) onto an image field (7) in an image plane (9). The objective includes a first partial objective (11) imaging the object field onto a first real intermediate image (13), a second partial objective (15) imaging the first intermediate image onto a second real intermediate image (17), and a third partial objective (19) imaging the second intermediate image onto the image field. The second partial objective is a catadioptric objective having exactly one concave mirror and having at least one lens (L21, L22). A first folding mirror (23) deflects the radiation from the object plane toward the concave mirror and a second folding mirror (25) deflects the radiation from the concave mirror toward the image plane. At least one surface of a lens (L21, L22) of the second partial objective has an antireflection coating having a reflectivity of less than 0.

Abstract: The disclosure relates to an illumination system for EUV lithography, as well as related elements, systems and methods. In some embodiments, an illumination system includes a first optical element and a second optical element. The first optical element can include a plurality of first facet elements configured so that, when impinged by respective partial beams of radiation, the plurality of first facet elements produce secondary light sources. The second optical element can include a second optical element including a plurality of second facet elements. Each of the plurality of second facet elements can be assigned to at least one of the plurality of first facet elements. The plurality of second facet elements can be configured to be impinged by the radiation via the first optical element.

Abstract: A film element of an EUV-transmitting wavefront correction device is arranged in a beam path and includes a first layer of first layer material having a first complex refractive index n1=(1??1)+i?1, with a first optical layer thickness, which varies locally over the used region in accordance with a first layer thickness profile, and a second layer of second layer material having a second complex refractive index n2=(1??2)+i?2, with a second optical layer thickness, which varies locally over the used region in accordance with a second layer thickness profile. The first and second layer thickness profiles differ. The deviation ?1 of the real part of the first refractive index from 1 is large relative to the absorption coefficient ?1 of the first layer material and the deviation ?2 of the real part of the second refractive index from 1 is small relative to the absorption coefficient ?2 of the second layer material.

Abstract: Catadioptric projection objective (1) for microlithography for imaging an object field (3) in an object plane (5) onto an image field (7) in an image plane (9). The objective includes a first partial objective (11) imaging the object field onto a first real intermediate image (13), a second partial objective (15) imaging the first intermediate image onto a second real intermediate image (17), and a third partial objective (19) imaging the second intermediate image onto the image field. The second partial objective is a catadioptric objective having exactly one concave mirror and having at least one lens (L21, L22). A first folding mirror (23) deflects the radiation from the object plane toward the concave mirror and a second folding mirror (25) deflects the radiation from the concave mirror toward the image plane. At least one surface of a lens (L21, L22) of the second partial objective has an antireflection coating having a reflectivity of less than 0.

Abstract: The invention relates to a device for expanding a laser beam, in particular a UV laser beam, comprising: a telescope arrangement having two spherical folding mirrors for expanding the incident collimated laser beam and a lens which is arranged in the divergent beam path downstream of the telescope arrangement and which has a spherical lens face for collimating the expanded laser beam, the first folding mirror in the beam path being a convex-curved spherical folding mirror and the second folding mirror in the beam path being a concave-curved spherical folding mirror. The invention also relates to an associated method for expanding a laser beam.

Abstract: A multi-band refractive optical imaging system. In one example, the system includes a plurality of lenses configured to receive and propagate electromagnetic radiation in at least the visible spectral band and the longwave infrared (LWIR) spectral band, the plurality of lenses including a first group of lenses of a first crown material, at least one lens of a first flint material, and at least one lens of a second material different than the first crown material and the first flint material. The plurality of lenses includes at least one crown-flint pair configured as an achromat to provide color correction in the visible and/or LWIR spectral bands. The system also includes a first beamsplitter configured to separate the electromagnetic radiation into the visible spectral band and the LWIR spectral band, and a rear external aperture stop positioned between the plurality of lenses and the first beamsplitter.

Abstract: An afocal telescope configured for back-scanned imagery including a three mirror anastigmat and an optical element positioned proximate an intermediate image plane of the three mirror anastigmat and configured to adjust distortion characteristics of the afocal telescope to control image wander on a focal plane array. The optical element may be a field correcting lens or mirror, for example.

Abstract: A collector for a projection exposure apparatus for microlithography comprises a plurality of reflective sections which are embodied and arranged in such a way that they can be impinged upon during the focusing of radiation from a first focus into a second focus with angles of impingement in a predefined angular spectrum.

Abstract: An imaging optical system has a plurality of mirrors. These image an object field in an object plane into an image field in an image plane. In the imaging optical system, the ratio of a maximum angle of incidence of imaging light) on reflection surfaces of the mirrors and an image-side numerical aperture of the imaging optical system is less than 33.8°. This can result in an imaging optical system which offers good conditions for a reflective coating of the mirror, with which a low reflection loss can be achieved for imaging light when passing through the imaging optical system, in particular even at wavelengths in the EUV range of less than 10 nm.

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 has a first, refractive objective part for imaging the pattern provided in the object plane into a first intermediate image; a second objective part including at least one concave mirror for imaging the first Intermediate imaging into a second intermediate image; and a third, refractive objective part for imaging the second intermediate imaging onto the image plane; wherein the projection objective has a maximum lens diameter Dmax, a maximum image field height Y?, and an image side numerical aperture NA; wherein COMP1=Dmax/(Y?·NA2) and wherein the condition COMP1<10 holds.

Abstract: A catadioptric projection objective has a first objective part, defining a first part of the optical axis and imaging an object field to form a first real intermediate image. It also has a second, catadioptric objective part forming a second real intermediate image using the radiation from the first objective part. The second objective part has a concave mirror and defines a second part of the optical axis. A third objective part images the second real intermediate image into the image plane and defines a third part of the optical axis. Folding mirrors deflect the radiation from the object plane towards the concave mirror; and deflect the radiation from the concave mirror towards the image plane. The first part of the optical axis defined by the first objective part is laterally offset from and aligned parallel with the third part of the optical axis.

Abstract: An extreme ultraviolet light source apparatus using a spectrum purity filter capable of obtaining EUV light with high spectrum purity. The apparatus includes a chamber; a target supply unit for supplying a target material; a driver laser using a laser gas containing a carbon dioxide gas as a laser medium, for applying a laser beam to the target material to generate plasma; a collector mirror for collecting and outputting the extreme ultraviolet light radiated from the plasma; and a spectrum purity filter provided in an optical path of the extreme ultraviolet light, for transmitting the extreme ultraviolet light and reflecting the laser beam, the spectrum purity filter including a mesh having electrical conductivity and formed with an arrangement of apertures having a pitch not larger than a half of a shortest wavelength of the laser beam applied by the driver laser.

Abstract: An electromagnetic wave resonator comprising a body, wherein the body: has a structure extending essentially in a plane (r, ?), comprises a material in a region between limit radii ri and ro, where 0?ri<rO and ro corresponds to a radius of a convex hull () of the structure; and allows for electromagnetic wave propagation, and wherein an effective refractive index ne(r), as obtained from angularly averaging a refractive index of the material in the plane (r, ?), decreases within said region.

Abstract: An automated adaptive optics and laser projection system is described. The automated adaptive optics and laser projection system includes an adaptive optics system and a compact laser projection system with related laser guidance programming used to correct atmospheric distortion induced on light received by a telescope. Control of the automated adaptive optics and laser projection system is designed in a modular manner in order to facilitate replication of the system to be used with a variety of different telescopes. Related methods are also described.

Abstract: Catadioptric projection objective (1) for microlithography for imaging an object field (3) in an object plane (5) onto an image field (7) in an image plane (9). The objective includes a first partial objective (11) imaging the object field onto a first real intermediate image (13), a second partial objective (15) imaging the first intermediate image onto a second real intermediate image (17), and a third partial objective (19) imaging the second intermediate image onto the image field. The second partial objective is a catadioptric objective having exactly one concave mirror and having at least one lens (L21, L22). A first folding mirror (23) deflects the radiation from the object plane toward the concave mirror and a second folding mirror (25) deflects the radiation from the concave mirror toward the image plane. At least one surface of a lens (L21, L22) of the second partial objective has an antireflection coating having a reflectivity of less than 0.

Abstract: An extreme ultraviolet light source apparatus using a spectrum purity filter capable of obtaining EUV light with high spectrum purity. The apparatus includes a chamber; a target supply unit for supplying a target material; a driver laser using a laser gas containing a carbon dioxide gas as a laser medium, for applying a laser beam to the target material to generate plasma; a collector mirror for collecting and outputting the extreme ultraviolet light radiated from the plasma; and a spectrum purity filter provided in an optical path of the extreme ultraviolet light, for transmitting the extreme ultraviolet light and reflecting the laser beam, the spectrum purity filter including a mesh having electrical conductivity and formed with an arrangement of apertures having a pitch not larger than a half of a shortest wavelength of the laser beam applied by the driver laser.

Abstract: A multi-wavelength band imaging system including a beam splitter is provided, allowing image capturing means adapted to specific wavelength bands to be used such as from visible to near infrared, intermediate infrared and far infrared. The system may have a field of view of substantially (360) degrees about an optical axis of the system and may fit into a golf ball sized housing. The imaging system includes a first convex mirror and a second concave mirror. Some embodiments for imaging single or close wavelength bands and not requiring a beam splitter are equally provided. Also provided is a self-righting housing for an imaging system, for example as described above, which self-rights under the action of gravity, thereby disposing the imaging system in an appropriate orientation.

Abstract: An imaging optical system, in particular a projection objective, for microlithography, includes optical elements to guide electromagnetic radiation with a wavelength in a path to image an object field into an image plane. The imaging optical system includes a pupil, having coordinates (p, q), which, together with the image field, having coordinates (x, y) of the optical system, spans an extended 4-dimensional pupil space, having coordinates (x, y, p, q), as a function of which a wavefront W(x, y, p, q) of the radiation passing through the optical system is defined. The wavefront W can therefore be defined in the pupil plane as a function of an extended 4-dimensional pupil space spanned by the image field (x, y) and the pupil (p, q) as W(x, y, p, q)=W(t), with t=(x, y, p, q).