Abstract: The invention provides a telescope system for inputting an image and presenting the image to a user. The telescope system includes a first array of flat mirrors including a plurality of first mirrors, the image, being light information, incident upon and reflected by each of the first array of mirrors; a primary reflecting curved mirror, each of the first mirrors reflecting light information onto the primary reflecting curved mirror; and a light collection portion, the light collection portion collecting and combining light information, originating from each of the first mirrors, so as to present a viewable image.

Abstract: The optical system includes a first set of optics, an optical switch and a second set of optics. The first set of optics is capable of receiving light and directing the light along a first optical path. The optical switch is capable of directing a first portion of the light to continue along the first optical path, and directing a second portion of the light along a second optical path. The second set of optics is subsequent to the optical switch and is capable of receiving the first portion of light from the optical switch, and directing that portion of light along a third optical path. The third optical path and the second optical path are substantially co-aligned. The optical system has variable magnifications and requires no moving parts.

Abstract: An objective is configured with a first partial objective and a second partial objective. The first partial objective, which projects a first field plane onto an intermediate image, has a first, convex mirror and a second, concave mirror. The second partial objective, which projects the intermediate image onto a second field plane, has a third and a fourth mirror, both concave. All of the four mirrors have central mirror apertures. The axial distance between the first and second mirrors is in a ratio between 0.95 and 1.05 relative to the distance between the second mirror and the intermediate image. The axial distance ZM3-IM between the third mirror and the second field plane conforms to the relationship 1 0.03 · Du M3 + 5.0 ⁢   ⁢ mm < Z M3 - IM < 0.25 · Du M3 tan ⁡ ( arcsin ⁡ ( NA ) ) .

Abstract: An aberration-correcting optical relay for an optical system. The relay comprises front and rear converging optical units together with a correcting meniscus or two correcting meniscuses placed symmetrically relative to each other, the meniscus(es) having main faces that are substantially concentric, and preferably exactly concentric, the two converging optical units being placed on a common axis and the correcting meniscus(es) being placed on said axis between the two converging optical units. The front converging optical unit situated upstream from the correcting meniscus(es) is placed in such a manner that the distance from an image point of the portion of the optical system upstream from the optical relay to the front converging optical unit is equal to the focal length of the front converging optical unit, said unit thus transforming a beam coming from said image point into a parallel beam.

Abstract: A projection exposure lens system has an object side catadioptric system, and intermediate image and a refractive lens system. The refractive lens system from its intermediate image side and in the direction of its image plane has a first lens group of positive refractive power, a second lens group of negative refractive power, a third lens group of positive refractive power, a fourth lens group of negative refractive power, and a fifth lens group of positive refractive power.

Abstract: An optical system has a light source of an optical beam, and a wavefront distortion generator that introduces a known wavefront distortion into at least one wavelength component of the optical beam prior to the formation of an intermediate image. A focusing device receives the optical beam, produces the intermediate image of the optical beam, and outputs the optical beam. A wavefront distortion corrector, after the formation of the intermediate image, introduces a wavefront distortion correction into each component of the optical beam into which the known wavefront distortion was introduced by the wavefront distortion generator. The wavefront distortion correction is the reverse of the known wavefront distortion introduced into the optical beam by the wavefront distortion generator.

Abstract: A photolithographic reduction projection catadioptric objective includes a first optical group having an even number of at least four mirrors and having a positive overall magnifying power, and a second substantially refractive optical group more image forward than the first optical group having a number of lenses. The second optical group has a negative overall magnifying power for providing image reduction. The first optical group provides compensative aberrative correction for the second optical group. The objective forms an image with a numerical aperture of at least substantially 0.65, and preferably greater than 0.70 or still more preferably greater than 0.75.

Abstract: An imaging spectrometer includes an all-reflective objective module that receives an image input and produces an objective module output at an exit slit, and an all-reflective collimating-and-imaging module that receives the objective module output as an objective-end input and produces a collimating-end output, wherein the collimating-and-imaging module comprises a reflective triplet. A dispersive element receives the collimating-end output and produces a dispersive-end input into the collimating-and-imaging module that is reflected through the collimating-and-imaging module to produce a spectral-image-end output. An imaging detector that receives the spectral-image-end output of the collimating-and-imaging module. The objective module may be a three-mirror anastigmat having an integral corrector mirror therein, or an all-reflective, relayed optical system comprising a set of five powered mirrors whose powers sum to substantially zero.

Abstract: An optical system has a correction half-sphere lens having multiple secondary mirrors mounted on an outer periphery of the correction half-sphere lens. A primary half-sphere mirror is coaxial and shares a same curvature center with the correction half-sphere lens. The primary half-sphere mirror has multiple through holes each corresponding to one of the secondary mirrors and having a second correction lens received therein to receive light from the corresponding secondary mirror. A cap is provided on top of the primary half-sphere mirror and has a shutter in a center of the cap to control incident light coming to the system.

Abstract: An optical architecture for observation telescopes, in particular for telescopes intended to be installed on board a vehicle, such as a space satellite, for observing terrestrial areas, includes a concave and off-axis mirror which is aspherical or possibly spherical and reflects in the form of a convergent beam a beam consisting of radiation that it receives from a terrestrial area that it is observing, a dioptric and achromatic aperture correction plate inserted on the path of the convergent beam reflected by the mirror, a dioptric and achromatic field correction plate inserted on the path of the convergent beam reflected by the mirror on the downstream side of the aperture correction plate relative to the mirror, and a pupil on the path of the reflected convergent beam to obtain an off-axis field of view preventing central obscuration. It constitutes a simple way of imaging stereoscopically.

Abstract: A single sensor that can operate in multiple bands and display either one radiation band alone or multiple overlaid bands, using an appropriate color choice to distinguish the bands. The multiple-band sensor allows the user to look through at least one eyepiece and with the use of a switch, see scenes formed via the human eye under visible light, an II sensor, an MWIR sensor, or an LWIR sensor, either individually or superimposed. The device is equipped with multiple switching mechanisms. The first, for allowing the user to select between radiation bands and overlays, and the second, as with most thermal imaging sensors, for allowing the user to switch between “white-hot/black-hot” i.e., a polarity switch.

Abstract: A system and method for simultaneous imaging of both infrared and millimeter wave radiation. The novel optical system (10) includes a primary mirror (20), a Mangin secondary mirror (30) positioned to receive energy reflected from the primary mirror (20), and an immersion lens (40) for focusing energy received from the Mangin mirror (30). In the illustrative embodiment, the primary mirror (20) and Mangin mirror (30) are arranged in a Cassegrain configuration. Central to this invention is the use of a negative power refractive Mangin mirror (30) as the Cassegrain secondary mirror, so that the field curvature of the secondary mirror (30) and immersion lens (40) can be made to cancel. The immersion lens (40) effectively decreases the wavelength of the millimeter wave radiation, allowing a smaller detector to collect the same amount of radiation as would a larger detector in air.

Abstract: A photolithographic reduction projection catadioptric objective includes a first optical group having an even number of at least four mirrors and having a positive overall magnifying power, and a second substantially refractive optical group more image forward than the first optical group having a number of lenses. The second optical group has a negative overall magnifying power for providing image reduction. The first optical group provides compensative aberrative correction for the second optical group. The objective forms an image with a numerical aperture of at least substantially 0.65, and preferably greater than 0.70 or still more preferably greater than 0.75.

Abstract: An optical system comprises a three-mirror anastigmat including a primary mirror, a secondary mirror, and a tertiary mirror positioned to reflect a beam path. An intermediate image is formed on the beam path at an intermediate-image location between the secondary mirror and the tertiary mirror. A negative-optical-power field mirror is positioned in the beam path at a field-mirror location subsequent to the intermediate-image location along the beam path. The field mirror reflects the intermediate image to the tertiary mirror.

Abstract: An all-reflective, relayed optical system is arranged along a beam path. The optical system includes a first mirror having positive optical power, and a second mirror having a negative optical power, wherein the second mirror receives the beam path reflected from the first mirror and wherein an intermediate image is formed after the beam path reflects from the second mirror. The optical system further includes a third mirror having positive optical power, wherein the intermediate image on the beam path is reflected from the third mirror; a fourth mirror having a negative optical power, wherein the beam path reflected by the third mirror is reflected by the fourth mirror, and a fifth mirror having positive optical power, wherein the beam path reflected by the fourth mirror is reflected by the fifth mirror to an image location.

Abstract: Techniques for generating partially coherent radiation and particularly for converting effectively coherent radiation from a synchrotron to partially coherent EUV radiation suitable for projection lithography.

Abstract: A compact telescope having a modified Gregorian design comprising three reflecting surfaces. The first reflecting surface is concave and is defined by an outer perimeter and an inner perimeter. The curvature of the first reflecting surface defines a focal plane of the first reflecting surface. The second reflecting surface is optically coupled to the first reflecting surface and is disposed between the first reflecting surface and the focal plane defined by the first reflecting surface. The third reflecting surface is concave and is disposed within the inner perimeter of the first reflecting surface. The curvature of the third reflecting surface is greater than the curvature of the first reflecting surface. The third reflecting surface is optically coupled to the first reflecting surface by the second reflecting surface. An aperture is disposed within the third reflecting surface. Thus light incident upon the first reflecting surface is directed through the aperture.

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 reflection type projection optical system includes six mirrors that serve substantially as a coaxial system, and include, in order from an object side to an image side, a first mirror, a second mirror, a third mirror, a fourth mirror, a fifth mirror, and a sixth mirror to sequentially reflect light, wherein the reflection type projection optical system serves as an imaging system that forms an intermediate image along an optical path between the third mirror and the fifth mirror, and wherein a displacement direction of a principal ray viewed from an optical axis from the first mirror to the second mirror is reverse to that from the third mirror to the sixth mirror.

Abstract: A cataoptric projection optical system for projecting a pattern on an object surface onto an image surface and for serving as an imaging system that forms an intermediate image includes first, second, third and fourth mirrors serving substantially as a coaxial system so as to sequentially reflect light from an object side to an image side, and being arranged so that light from the object surface to the first mirror may intersect light from the second mirror to the third mirror.

Abstract: A zoom strobe device is provided with a light emitting unit, which includes a light source and a reflector and a light collecting lens that collects the light emitted by the light emitting unit. The light emitting unit and the light collecting lens are movable relative to each other in a direction of an optical axis of the light collecting lens. The light collecting lens is configured such that a light emitting unit side surface has a positive power, and a surface opposite to the light emitting unit side surface (i.e., the object side surface) has a negative power. The light collecting lens has a positive power as a whole.

Abstract: An optical switching system and apparatus includes a plurality of micro-machined mirrors and a covering lens for adjusting the optical field of at least one of the plurality of micro-machined mirrors. The covering lens has a positive focal length.

Abstract: A reduction objective, a projection exposure apparatus with a reduction objective, and a method of use thereof are disclosed. The reduction objective has a first set of multilayer mirrors in centered arrangement with respect to a first optical axis, a second set of multilayer mirrors in centered arrangement with respect to a second optical axis, and an additional mirror disposed at grazing incidence, such that said additional mirror defines an angle between the first optical axis and said second optical axis. The reduction objective has an imaging reduction scale of approximately 4× for use in soft X-ray, i.e.

Abstract: A spotlight has a curved reflector (1, 1′) and a lamp (2, 2′) arranged inside a cavity formed by the reflector (1, 1′). The lamp (2, 2′) and the reflector (1, 1′) are movable relative to one another in a direction of a main optical axis of the spotlight. A converging lens (5) is arranged in front of the reflector (1, 1′) in a direction of light emission. A dispersive lens (6) is arranged between the reflector (1, 1′) and the converging lens (5).

Abstract: An illumination system and condenser for use in photolithography in the extreme ultraviolet wavelength region having a first non-imaging optic element collecting electromagnetic radiation from a source and creating a desired irradiance distribution and a second non-imaging optic element receiving the electromagnetic radiation from the first non-imaging optic element and redirecting and imaging the electromagnetic radiation. The electromagnetic radiation emanating from the second non-imaging optic element is suitable for being received by other conventional optical surfaces to provide a desired irradiance distribution with a desired angular distribution and desired shape. Facets are used to provide the desired illumination over the desired illumination field. Reflective facets may be placed on the second non-imaging optic, which can reduce the number of mirrors and increase efficiency.

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.

Abstract: Disclosed is a reflecting optical system in which a beam from an object is incident through an incident surface formed in a surface of a transparent body, the beam is reflected by a reflecting surface of internal reflection comprised of a curved surface provided in a part of the transparent body, and thereafter the beam is emergent from an emergent surface of the transparent body, thereby forming an image, wherein a radius of curvature of the incident surface is set to be nearly equal to a distance from the vertex of the incident surface to the object on a reference axis and wherein a radius of curvature of the emergent surface is set to be nearly equal to a distance from the vertex of the emergent surface to the image on the reference axis.

Abstract: A reflection type demagnification projection optical system that uses light of light with a wavelength of 200 nm or less includes six light-reflecting mirrors arranged from an object side to an image side such that said mirrors basically form a coaxial system, wherein a third mirror in said six mirrors is located at a pupil position of said optical system.

Abstract: A compact reflector telescope has a spherical primary reflector and a secondary reflector with a negative lens interposed there between in axial alignment therewith. Light reflected from the primary reflector is passed through the negative lens and is diverted by the secondary reflector to a positive lens at the side of the telescope tube. The positive lens focuses the light rays onto an eye piece or ocular or onto a photographic emulsion or electronic detector. The telescope reduces or substantially eliminates spherical aberration and can be configured to have a focal ratio significantly greater than the focal ratio of the primary reflector. The telescope produces a flat field of view and an image which is substantially diffraction limited.

Abstract: The present invention relates to a high numerical aperture exposure system having a wafer. The exposure system in the present invention includes a beam-splitter, a reticle, a reticle optical group, where the reticle optical group is placed between the reticle and the beam-splitter, a concave mirror, a concave mirror optical group, where the concave mirror optical group is placed between the concave mirror and the beam-splitter, a fold mirror, where the fold mirror is placed between the beam-splitter and the wafer, and a wafer optical group, where the wafer optical group is placed between the beam-splitter and the wafer. In the present invention, a beam of light is directed through the reticle and the reticle optical group to the beam-splitter, then it is reflected by the beam-splitter onto the concave mirror. Concave mirror reflects the light onto the fold mirror through the beam-splitter. Fold mirror reflects the light onto the wafer through the wafer optical group.

Abstract: The present invention discloses an image-forming optical system provided with a plurality of curved mirrors whereby two points at different distances are made to have an optically conjugate relationship, sequentially starting with a first conjugate point which is nearer when an optical path is traced from the first conjugate point to a second conjugate point which is farther, comprises, a first mirror which reflects luminous flux from the first conjugate point to transform the luminous flux into substantially parallel luminous flux, and a second mirror which reflects the luminous flux reflected by the first mirror while keeping the luminous flux substantially parallel.

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 system for multiple mode imaging is disclosed herein. The system is a catadioptric system preferably having an NA greater than 0.9, highly corrected for low and high order monochromatic aberrations. This system uses unique illumination entrances and can collect reflected, diffracted, and scattered light over a range of angles. The system includes a catadioptric group, focusing optics group, and tube lens group. The catadioptric group includes a focusing mirror and a refractive lens/mirror element. The focusing optics group is proximate to an intermediate image, and corrects for aberrations from the catadioptric group, especially high order spherical aberration and coma. The tube lens group forms the magnified image. Different tube lens groups can be used to obtain different magnifications, such as a varifocal tube lens group to continuously change magnifications from 20 to 200×. Multiple imaging modes are possible by varying the illumination geometry and apertures at the pupil plane.

Abstract: A projection exposure lens system has an object side catadioptric system, and intermediate image and a refractive lens system. The refractive lens system from its intermediate image side and in the direction of its image plane has a first lens group of positive refractive power, a second lens group of negative refractive power, a third lens group of positive refractive power, a fourth lens group of negative refractive power, and a fifth lens group of positive refractive power.

Abstract: The invention is concerned with a microlithography projection objective device for short wavelength microlithography, preferably <100 nm, with a first mirror (S1), a second mirror (S2), a third mirror (S3), a fourth mirror (S4) and a fifth mirror (S5). The invention is characterized by the fact that the image-side numerical aperture (NA) is greater than or equal to 0.10 and that the mirror closest to the object to be illuminated, preferably the wafer, is arranged in such a way that the image-side optical free working distance corresponds at least to the used diameter (D) of the mirror closest to the wafer; the image-side optical free working distance is at least the sum of one-third of the used diameter (D) of the mirror closest to the wafer and a length which lies between 20 mm and 30 mm; and/or the image-side optical free working distance is at least 50 mm, preferably 60 mm.

Abstract: A reflector for reflecting light from an elongate light source into the input end of a light guide having a diameter “D”. The light source is inserted through the narrow end of a collimating reflector which has a wide end with a diameter exceeding “D” through which light is emitted into the guide. The wide end of an output reflector circumferentially surrounds the collimating reflector's wide end. The output reflector's narrow end circumferentially surrounds the light guide's input end. The wide end of an input reflector circumferentially surrounds the collimating reflector's narrow end. The reflectors are cylindrically symmetrical about a common axis. Light passing from the light source to the collimating reflector is reflected, producing an output beam whose width varies as a function of distance along the axis. The light guide's input end is positioned along the axis to minimize the width of the output light beam.

Abstract: The present invention relates to an omnidirectional wide angle optical system, which is associated with a sensor, camera, projector, medical instrument, surveillance system, flight control system, robotic command and control or sensing system, home entertainment system, conference area, virtual reality suite, theater, or similar article. The optical system consists of an external refracting surface which may be strongly curved, an strongly curved internal primary reflector surface, a secondary reflector surface (in most embodiments), central wide angle refracting optics (in some embodiments), a modular or integral imaging and correcting lens system which may have aperture adjustment means, and mounting components.

Abstract: A free-space wireless optical communication system is disclosed that utilizes a telescope design having aspherical mirrors, such as a Ritchey-Chretien (RC) telescope. RC telescopes are characterized by a concave primary mirror and a convex secondary mirror each having a hyperbolic shape. The disclosed mirror configuration provides a larger focal plane that allows for automatic alignment between a transmitter and receiver with a stationary or fixed mirror design, further contributing to a lower fabrication cost. Among other benefits, the larger focal plane permits an n×n fiber array to be positioned in the focal plane of the RC optical telescope, thereby enabling point-to-multipoint communications with a single optical telescope. Each fiber in the n×n fiber array of a transmitting telescope can be focused on a different receiving telescope in a wireless optical communication system.

Abstract: The invention is directed to a directionally adjustable telescope arrangement (1) having a first arcuate mirror (3), a second arcuate mirror (9) and a planar deflecting mirror (13). A third arcuate mirror (17) is provided in the imaging beam path of the telescope arrangement (1). The mirror (17) coacts with the first arcuate mirror (3) and the second arcuate mirror (9) to effectively form images.

Abstract: A telescope apparatus for celestial observations by a reflecting telescope which is provided with: a first reflecting mirror 3 having its surface 3a coated over the entire area thereof with a grid-like metallic film 10 that reflects radio waves 1 but permits the passage therethrough of infrared and visible rays 2 and having its back 3b coated over the entire area thereof with a full-face metallic film that reflects both of the radio waves 1 and the infrared and visible rays 2; and a second reflecting mirror 4 having its surface 4a coated over the entire area thereof with the grid-like metallic film 10 that reflects the radio waves 1 but permits the passage therethrough of the infrared and visible rays 2 and having its back 4b coated over the entire area thereof with the full-face metallic film 11 that reflects both of the radio waves 1 and the infrared and visible rays.

Abstract: In a method for correcting optical wavefront errors in an optical system, the optical wavefront is calculated for different wavelengths and fields of view between the entry pupil (EP) and exit pupil (AP). Any phase differences are compensated by at least one surface (5, 7) compensating the phase differences in the beam path. A particular optical system, expediently in the form of a telescope, accordingly has a beam path which comprises the following: a first reflector (3), arranged along its axis (A), for reflecting a beam (1) incident along an optical axis (O) onto a concave second reflector (4) which throws the beam obtained from the first reflector (3) onto a third reflector (5), from which it is passed to a concave fourth reflector (6) in order to be reflected at an angle with said optical axis (O). Such a means (5, 7) for correcting the wavefront errors is provided in the beam path of such an optical system.

Abstract: An optical system compatible with short wavelength (extreme ultraviolet) radiation comprising four optical elements providing five reflective surfaces for projecting a mask image onto a substrate. The five optical surfaces are characterized in order from object to image as concave, convex, concave, convex and concave mirrors. The second and fourth reflective surfaces are part of the same optical element. The optical system is particularly suited for ring field step and scan lithography methods. The invention uses aspheric mirrors to minimize static distortion and balance the static distortion across the ring field width, which effectively minimizes dynamic distortion.

Abstract: An ultraviolet (UV) catadioptric imaging system, with broad spectrum correction of primary and residual, longitudinal and lateral, chromatic aberrations for wavelengths extending into the deep UV (as short as about 0.16 &mgr;m), comprises a focusing lens group with multiple lens elements that provide high levels of correction of both image aberrations and chromatic variation of aberrations over a selected wavelength band, a field lens group formed from lens elements with at least two different refractive materials, such as silica and a fluoride glass, and a catadioptric group including a concave reflective surface providing most of the focusing power of the system and a thick lens providing primary color correction in combination with the focusing lens group. The field lens group is located near the intermediate image provided by the focusing lens group and functions to correct the residual chromatic aberrations. The system is characterized by a high numerical aperture (typ, greater than 0.

Abstract: An optical architecture for observation telescopes, in particular for telescopes intended to be installed on board a vehicle, such as a space satellite, for observing terrestrial areas, includes a concave and off-axis mirror which is aspherical or possibly spherical and reflects in the form of a convergent beam a beam consisting of radiation that it receives from a terrestrial area that it is observing, a dioptric and achromatic aperture correction plate inserted on the path of the convergent beam reflected by the mirror, a dioptric and achromatic field correction plate inserted on the path of the convergent beam reflected by the mirror on the downstream side of the aperture correction plate relative to the mirror, and a pupil on the path of the reflected convergent beam to obtain an off-axis field of view preventing central obscuration. It constitutes a simple way of imaging stereoscopically.

Abstract: An optical system has an aperture stop, and an optical unit placed on the image side of the aperture stop. The optical unit consists of the following components in the order named from the object side: a first optical component with a reflective curved surface, for forming an intermediate image of an object, a second optical component with a reflective curved surface, for forming an image of the aperture stop with light from the intermediate image of the object, and a third optical component with a reflective curved surface, for forming a secondary image of the object with light from the image of the aperture stop. When fB1(&thgr;), fB2(&thgr;), and fB3(&thgr;) are focal lengths of the first optical component, the second optical component, and the third optical component, respectively, at an azimuth &thgr;, the focal lengths satisfy the following conditions in the azimuth range of 0<&thgr;<2&pgr;: fB1(&thgr;)>0, fB2(&thgr;)<0, fB3(&thgr;)>0.

Abstract: A centrally-obscured reflective telescope having a semi-active focus and thermal compensation system. The telescope has a housing having an input window, a primary mirror, a secondary mirror suspended between the input window and the primary mirror by support struts, an optional tertiary mirror, and an optional fold mirror. The system includes one or more heating elements respectively disposed on each of the support struts. A first temperature sensor (disposed on the primary mirror) generates a reference temperature, a second temperature sensor is disposed on the secondary mirror, and one or more third temperature sensors are disposed on each of the support struts. A temperature compensation controller is coupled to the heating elements and temperature sensors and controls the heat output of the plurality of heating elements to heat the support struts and control the position of the secondary mirror relative to the primary mirror.

Abstract: A two-stage multi-spectral imaging system comprising a reflective objective and a reflective relay aligned on a common optical axis, the objective being arranged to form an intermediate image and the relay being arranged to deliver image-forming radiation emanating from the intermediate image to a focal plane, wherein the objective is formed by a large concave primary mirror which is apertured on-axis and a small secondary mirror generally disposed in the form of a “Cassegrain” objective, the relay is formed by a pair of confronting mirrors each being apertured on-axis to enable passage of radiation into and out of the relay, and the relay being positioned to provide space between the relay and the focal plane to accommodate waveband selective splitting optics if so desired.

Abstract: The invention relates to a wide-angle catoptric system. The system comprises a convex primary mirror (M1), a secondary mirror (M2), a tertiary mirror (M3), and a quaternary mirror (M4), and it is characterized in that the secondary mirror (M2) is convex. The invention is particularly applicable to astronomical or space observation over a broad spectral range.

Abstract: A catadioptric anamorphic beam expanding telescope expands an optical beam in a first axis substantially perpendicular to the beam propagation axis, and deflects it in a plane substantially perpendicular to the first axis. The beam expanding telescope can include reflective, refractive, and combined reflective/refractive elements. An embodiment includes an off axis convex spheric reflector and an off axis combined reflective/reflective optical element, commonly known as a Mangin mirror, incorporating a refractive first surface and a reflective rear surface, which compensate for aberrations introduced by the off axis deflection of the beam. The telescope is particularly useful for deep ultraviolet (DUV) applications at wavelengths shorter than about 250 nm. In some applications, the telescope illuminates a diffraction grating or other wavelength dispersive element, aligned to retroreflect a preferential wavelength, thereby providing wavelength narrowing.

Abstract: Disclosed is a reflecting optical system in which a beam from an object is incident through an incident surface formed in a surface of a transparent body, the beam is reflected by a reflecting surface of internal reflection comprised of a curved surface provided in a part of the transparent body, and thereafter the beam is emergent from an emergent surface of the transparent body, thereby forming an image, wherein a radius of curvature of the incident surface is set to be nearly equal to a distance from the vertex of the incident surface to the object on a reference axis and wherein a radius of curvature of the emergent surface is set to be nearly equal to a distance from the vertex of the emergent surface to the image on the reference axis.