Abstract: A catadioptric reduction objective has a concave mirror 19', a beam splitter 150' and several lens groups (100', 200'; 300', 400'). The system diaphragm 40' is mounted between beam splitter surface 15' and image plane 36' and especially within the last lens group 400'. NA=0.7; for UV, DUV; image side or both sides telecentric; also achromatized.

Abstract: An imaging lens system consisting of a front lens unit which comprises a negative lens component disposed on the image side and has a positive refractive power, and a rear lens unit which is composed of a positive lens component: a distance ffb as measured from an object side surface of the rear lens unit to a front focal point of the rear lens unit, a distance D as measured from an exit pupil of the front lens unit to an object side surface of the rear lens unit, and refractive powers of the front lens unit and the rear lens unit being adequately defined for the imaging lens system.

Abstract: A double sided telecentic measurement objective for contactless length measurement in two-dimensional and three-dimensional space. The objective has an image-side optical system consisting of three elements equivalent to those of an object-side optical system but in the reverse order, including a cemented positively refracting lens element turned toward the object of image respectively, a collecting lens spaced by an air gap from the cemented lens, and a dispersive meniscus spaced by an air gap from the collecting lens. The widths of the air gaps between the collecting lenses and the meniscus are substantially greater than the widths of air gaps between the cemented lens elements and the collecting lenses.

Abstract: A unit magnification lens system suitable for imaging of features in photoresist designed for exposure at a wavelength of 248.4 nm using a krypton fluoride excimer laser. This lens system is characterized by a very long working distance in the object and image spaces to allow incorporation of minors in the imaging path. The optical system is refractive, telecentric, and symmetrical about the central aperture stop.

Abstract: An objective lens is secured in an afocal mode to a support for movement vertically toward and away from a workpiece. An illumination collimator fixed on the support above the objective lens projects the image of a reticle downwardly and successively through a second lens assembly, a beamsplitter plate, and coaxially of the objective lens to the workpiece. A combined image of the reticle and workpiece is then projected by the objective lens upwardly onto the beamsplitter, and laterally to a mirror which projects the combined image upwardly along an axis spaced from and parallel to the axis of the objective lens, and through one of several different magnifying lens assemblies to the image detector of a video camera. The magnifying lens assemblies can be selectively indexed one at a time into registry with the camera, and each has a telecentric opening or stop which always registers with the rear focal point of the objective lens each time such assembly is indexed into its operative position.

Abstract: Telecentric lens systems for use with pixelized panels, such as LCD or DMD panels, are provided. The systems have a long aperture stop to object distance (ASOD) and a high level of aberration correction, including a high level of lateral color correction. Preferably, the systems also have a low f-number and are wide angle. The systems include a negative first unit which produces the long ASOD, a weak second unit which includes two meniscus elements which surround the system's aperture stop, and a positive third unit which images the aperture stop to form the system's telecentric pupil.

Abstract: The present invention is directed to an optical system which includes an image region having at least one light source which directs a beam of light along an optical axis and an object region which is adapted to receive the light from the light source. An optical delivery system is between the image region and object region. The optical delivery system receives the light from the image region and directs it to the object region. The optical delivery system is formed of a plurality of optical elements, such as lenses and volume holograms. The optical delivery system is designed to either receive a plurality of beams of light from a plurality of sources or different modes of a single light source and form a single spot of light in the image region having the combined power of all of the beams of light or modes of a single beam. The optical delivery system can also condense or expand the spacing between the beams of light from a plurality of light sources.

Abstract: An observation optical system for endoscopes configured so as to allow observation of objects located in liquids, comprising an objective lens system and relay lenses for relaying an image formed by the objective lens system, and satisfies the following conditions (1) and (2):0.08.ltoreq.N.sub.w .multidot.f tan [sin.sup.-1 {(1/N.sub.w) sin .theta..sub.Al }]/I.sub.1 .ltoreq.1.18 (1)0.9.ltoreq.N.sub.w .multidot.f.multidot.tan[sin.sup.-1 {(1/N.sub.w) sin .theta..sub.A0.5 }]/I.sub.0.5 .ltoreq.1.1 (2)wherein the reference symbol f represents a focal length of the objective lens system, the reference symbol N.sub.w designates a refractive index of a liquid, the reference symbols .theta..sub.Al and .theta..sub.A0.5 denote field angles at the maximum image height and a half of the maximum image height in water respectively, and the reference symbols I.sub.1 and I.sub.0.5 represent a maximum image height and a half of the maximum image height.

Abstract: A telecentric imaging optical system has first and third lens systems each having a positive power, and a second lens system having a negative power. In the imaging optical system, the second lens system is disposed between the first and the third lens systems. The imaging optical system satisfies the following inequalities:f1/2.5<-f2<2.multidot.f1f3/2.5<-f2<2.multidot.f3where f1 is the focal length of the first lens system, f2 is that of the second lens system and f3 is that of the third lens system. A rear focal point of a composite lens system consisting of the first and the second lens systems substantially coincides with the front focal point of the third lens system. The telecentric imaging optical system has a large variable power ratio.

Abstract: An airspaced, diffraction limited, seven element telecentric f-theta lens having a first meniscus lens concave to the incident side; a first bi-concave lens; a second meniscus lens convex to the incident side; a third meniscus lens concave to the incident side; a pair of bi-convex lenses; and a second bi-concave lens is disclosed. The second, third and fourth as well as the sixth and seventh lens elements are edge contact spaced.

Abstract: An optical system of a projection display apparatus includes a projection lens assembly having a first lens group having a negative power, a second lens group having a negative power and a third lens group having a positive power, all arranged in this order from a side of a screen. An air space is provided between the first and second lens groups and also between the second and third lens groups. Each air space is longer than the entire length of the second lens group as taken along the optical axis of the assembly.

Abstract: A collimating lens (10) is constructed of a lens assembly having a first lens set (12, 14) at a first end of the assembly and a second lens set (20) at a second end of the assembly with a doublet (16, 18) disposed between the first lens set and the second lens set. The first lens set includes a plurality of lens elements (12, 14) each of which has positive optical power. The second lens set has a single lens element (26) of positive optical power and a concave surface (40) facing subject matter to be viewed by the collimating lens. The doublet lens element includes a lens element (16) constructed of flint glass and having a negative optical power plus a lens element (18) constructed of crown glass and having a positive optical power. In the doublet lens element, the negative power lens element has two concave surfaces, the positive-power lens element has two convex surfaces, and the two lens elements are cemented together to provide for a broad-band chromatic correction.

Abstract: A refractive inverse telephoto optical system (10) has a first lens doublet (12), a Pechan prism assembly (14) and a second lens doublet (16). The Pechan prism assembly (14) is spaced between the front negative doublet (12) and the rear positive doublet (16). The Pechan prism assembly (14) may be rotated and, as rotation occurs, the associated linear detector array is rotated around within the optical field of view.

Abstract: The invention is an inverted microscope with a housing having multiple integrated ray paths leading from the specimen being examined to (a) the viewer/operator and (b) one or more auxiliary ports used for image recording and/or measurement by accessories such as cameras and video recorders. The microscope lens is positioned below the specimen stage; and, positioned below the lens, is a simple reflector which deflects the combined rays from the lens diagonally upward toward the viewer at exactly the same angle at which the viewer looks into the microscope's binocular eyepieces. The position of this simple reflector is the lowest point in the unit's paths of rays, thereby significantly lowering the lens turret and, therefore, the specimen stage to a relatively low, ergonomically-appropriate position. The optical arrangement is simple and compact, minimizing the number of deflections in the path of the viewing rays.

Abstract: An objective lens system for endoscopes comprising, in the order from the object side, a first lens component having a negative refractive power, a second lens component having a positive refractive power, an aperture stop arranged right after the second lens component, and a rear lens unit comprising a third lens component designed as a cemented doublet consisting of a lens element having a positive refractive power and a lens element having a negative refractive power. Said objective lens system for endoscopes has a wide field angle, a compact design, a small number of lens elements and favorably corrected aberrations.

Abstract: A lens system is provided which includes two lens units. The first lens unit includes two meniscus lenses whose concave surfaces face each other and the second lens unit has a positive power. The system can be configured to have a wide field of view and/or to be telecentric. In its basic form, a well-corrected lens having a relatively large aperture and field of view is achieved through the use of only three lens elements.

Abstract: To easily correct color shading merely by adjusting the arrangement of an optical system. A light beam incident on a three prism type color separation optical system 1 having photographic devices 7, 8, 9 and guided to the photographic devices, is effectively telecentric on the side of the photographic devices.

Abstract: An objective optical system for endoscopes comprising, in the order from the object side, a front negative lens unit, an aperture stop, a positive lens unit comprising at least one positive lens component, and an infrared cut filter arranged immediately before said aperture stop, said objective optical system being adapted so as to allow rays to be incident on said filter at heights lower than the outside circumference of said filter.

Abstract: Source of laser radiation for a printer includes at least one laser diode array and an optical system which is telecentric in at least one azimuth for imaging the near field distribution from the laser diode array(s) on a recording medium.

Abstract: Modular illumination system for transmitted-light microscopes, embodying the Koehler illumination principle, and usable on microscopes of short or long optical transmission length, including a telecentering lens disposed in the light beam path defined according to Koehler between the luminous field diaphragm and the aperture diaphragm and imaging the luminous field diaphragm at infinity the telecentering lens is displaceable, preferably perpendicularly to the optical axis.

Abstract: A diffraction limited, f/6.0, 71.0 mm focal length telecentric scan lens which is color-corrected for 780 nm, 830 nm and 890 nm wavelengths. The lens includes, in succession from a side of incident light:a first negative meniscus lens element, concave toward the incident light side;a second positive meniscus lens element, concave toward the incident light side;a first plano-convex lens element, convex away from the incident light side;a second plano-convex lens element, convex toward the incident light side;a first cemented doublet including bi-concave and plano-convex lens elements, the cemented surface convex toward the incident light side; anda second cemented doublet including plano-concave and plano-convex lens elements, the cemented surface convex toward the incident light side.

Abstract: An exposure apparatus for use in fabricating a printed circuit board. A thermally-written liquid-crystal light valve is provided in which a pattern is formed by opaque portions and transparent portions. A writing optical system directs a heating spot light onto the light valve. The light valve and/or the heating spot light is movable, relative to the other. A projecting optical system is arranged which transmits a luminous flux emitted from a light source, through a liquid-crystal layer within the liquid-crystal light valve. The projecting optical system illuminates a subject with the transmitted luminous flux.

Abstract: A zoom lens is described for an electronic camera for still pictures, comprising a front group (G.sub.1), a variator group (G.sub.2) and a main group (G.sub.4). The lens is designed in such a manner that the sum of the spherical aberrations of the front group and the variator group is constant throughout the zoom range and is adapted to that of the main group.

Abstract: An optical scanning system has a deflector for deflecting a beam emitted from a light source portion, a telecentric scanning lens for focusing the deflected beam onto a scanning surface, a beam splitter for splitting a beam reflected by the scanning surface on an optical path between the deflector and the light source portion from an outgoing optical path, and a focus point detector for receiving the beam split by the beam splitter and detecting a focused state of the beam on the scanning surface.

Abstract: An optical system for endoscopes so adapted as to be usable with video endoscopes, comprising an imaging lens system equipped with an aperture stop and a field lens component arranged on the image side thereof, and so designed as to prevent the color shading from being produced by selecting an adequate focal length for the field lens component.