Abstract: In a method of manufacturing a correction lens for exposing a phosphor screen of a cathode ray tube, an effective surface of the correction lens is divided into a plurality of regions and an orbit of light beam corresponding to an orbit of electron beam is analyzed for each of regions to determine segment surface equation in the same expression form for the respective regions. A final surface equation is derived from the segment surface equations in consideration of an allowable error and the correction lens is formed on the basis of the final surface equation.

Abstract: A lens for a lamp having a non-planar portion in which a large number of Fresnel lens steps or prism steps are formed on the incident surface thereof, yet which produces a very parallel output beam. The lens steps are defined by a tangential vector at an arbitrary point of a refraction boundary surface (Fresnel lens steps) or a total-reflection surface (prism steps) which is in the same direction as an outer product of a normal vector of the refraction boundary surface or total-reflection surface and a normal vector of an exit surface of the lens at a refraction point where a ray refracted by the refraction boundary surface or total-reflection surface is refracted. A method is also disclosed for producing a die for forming such a lens.

Abstract: An eccentric Fresnel lens is formed from a concentric Fresnel lens sheet or Fresnel lens sheet mold. The concentric Fresnel lens sheet or mold is cut to produce an eccentric Fresnel lens having a center offset from the optical axis of the concentric Fresnel lens.

Abstract: The current limits of resolution of multi-element optical systems are exceeded by reducing the number of elements while introducing at the critical aperture a blazed transmission grating having grating rings of low bending power defined by multiple plateaus. By illuminating the optical train with monochromatic light that constitutes a multiplicity of distributed sources having a substantial temporal coherence but spatial incoherence and by varying the slopes and widths of the grating rings, local phase delays are introduced that adjust aberrations in the optical system, providing an aligned composite wavefront. The system and method may be used for presenting an image, as for a wafer stepper, or for viewing an image, as in a microscope.

Abstract: The present invention provides an optical system for a virtual reality head mounted display with improved image quality, enlarged field of view, and enhanced adjustability. In one embodiment, the optical system comprises a housing coupled to the frame of the head mounted display, a pair of displays mounted to the housing each defining a visual plane, and first and second lenses mounted between each of the displays and the user's eyes. The lenses are mounted to the housing such that each lens is disposed at an angle of between 1.degree. and 15.degree. relative to the visual plane. The lenses are also mounted such that the interoptic distance between the lenses may be adjusted. The optical system also has a unique lens construction including a standard Fresnel lens mounted in parallel to a low-diffraction Fresnel lens, resulting in substantially reduced diffractive interference.

Abstract: Stereo multi-vision scope with a pair of visual corn type tubes having an ocular portions and a pair of objects portions such as a conventional binocular type.The ocular portions have not optical lens and the objects portions have multi-image lenses to make a multitude of stereo visual image for viewing distant objects through it.The corn type tubes also have extension and shortening structure to control their respective distance or width in a horizontal state or position.

Abstract: Fresnel lens elements in a lens grouping and mounted in a fixed relationship to a detector, to define a 360.degree. field of view for use in a sensor for passive detection of infrared radiation. Lens elements of the lens grouping can be selected by masking other lens elements, to leave a lens array defining a particular pattern of detection for a desired application. By masking certain of the lenses of the lens grouping, wide angle three-dimensional or fan-like planar curtain patterns of detection are obtained for use of the sensor in either a wall-mounted or ceiling-mounted installation, and vertical curtains of coverage can be obtained using ceiling-mounted installation. Lens elements of different sizes and focal lengths are arranged to gather ample radiation for detection of distant intruders in certain directions.

Abstract: The invention relates to a windshield deflector shield for deflecting insects and debris above the hood and windshield of a vehicle and for increasing the driver's field of vision. The deflector shield includes a lens coupled to the middle deflector section for increasing the field of vision in front of the vehicle. The deflector shield may also include rearview mirrors coupled to the ends of the deflector shield for increasing the driver's field of vision at the sides of the vehicle.

Abstract: A zoom lens (10) has a first lens group (12), a second lens group (14) and a third lens group (16). The first lens group relays an outside scene to an intermediate plane. The second lens group varies magnification of the relayed image from the first lens group. Also, the second lens group includes at least one diffractive optical element. The third lens group compensates for focus shift and focuses the wavefront onto the viewing plane.

Abstract: A lens composed of a single material and having at least one refractive surface on one face and a kinoform on the other face. The purely refractive between the surfaces varies dimensionally and in refractive index in response to temperature changes and thereby changes a characteristic, such as back focal length, of the lens while the kinoform varies differently in response to the same temperature changes. The kinoform power is sufficient to vary the temperature induced characteristic changes of the lens in an opposing sense at a given wavelength and in an amount sufficient to athermalize the optical device. In one embodiment the kinoform power compensates for the combined temperature-induced effects upon the refractive portion and any mount that supports the lens.

Abstract: An illuminating optical system for use in a microfilm reader/printer or the like for illuminating a film comprises an axially symmetric lens system and an anamorphic lens system. The anamorphic lens system includes a condenser lens opposed to a light source. A microfilm reader/printer having such an illuminating optical system causes the axially symmetric lens system to illuminate the microfilm during a reading operation, and the anamorphic lens system to illuminate the film during a printing operation.

Abstract: A solar electric conversion unit and system includes substantially increased efficiency with reduced losses and increased acceptance angles. The system employs a short focal length fresnel lens extruded to further include depending side walls. The free edges of the sides carry a heat sink supporting a photovoltaic cell. The extruded side walls function as light pipes for carrying light directly to the photovoltaic cell. The walls are reflective inwardly of the unit to further avoid loss of stray light.

Abstract: The present invention provides an original scanning apparatus comprising, an original support plate on which an original is rested, a fixed point light source having a width smaller than that of the original support plate, a shiftable reflection member for reflecting light beams emitted from the light source toward the original support plate, and a first deflector member for deflecting the light beams emitted from the light source in a slit widthwise direction and a second deflector member for deflecting the light beams in a slit longitudinal direction, the first and second deflector members being formed discretely.

Abstract: A lens in a shape of cylinder or head-cut-off cone made of transparent thin film materials with a fine prism-shaped fresnel lens surface formed thereon. The cylindrical lens is manufactured by forming a fine prism-shaped linear fresnel lens surface on a thin transparent film, shaping the film into a cylinder or a frustum of a cone, and connecting both ends of the film so that the fresnel center line forms a horizontal ring.

Abstract: A cylindrical lens and a binary optical element for collimating with low optical aberrations an asymmetrically diverging input wavefront. The binary optical element is formed on a planar substrate on which a binary optical diffraction pattern is etched on the front surface thereof. The binary optical diffraction pattern is designed such that each ray of light from the diverging input light source will travel the same optical path length or vary from that optical path length by an integer multiple of the wavelength of the light in travelling from its source to its exit from the front surface of the binary optical element. A beam angle alignment element is also provided, to be utilized in conjunction with a cylindrical lens and the binary optical element, for correcting angular misalignments of diode lasers whose output wavefront has an optical axis which is either above or below the plane in which the active region is formed.

Abstract: A hybrid lens for collimating, with low optical aberrations, an asymmetrically diverging input wavefront. The hybrid lens has a front surface which serves to diffract the input wavefront and a back surface which serves to refract the wavefront. Embodiments are described comprised of either a single plano-convex optical lens or a pair of lenses, one of which is a plano lens and the other or which is plano-convex. In either alternative, the convex surface is spherical. The planar surface of the single plano-convex lens or the back lens surface of the plano lens is optimized such that each ray of light from a diverging input light source will travel the same optical path length in reaching a predetermined collimation plane. This optimization is done by means of binary optic technology which uses a reactive-ion etch to form the requisite eight-level binary optic diffraction pattern.

Abstract: The method utilizes high resolution lithography, mask aligning, and reactive ion etching. In particular, at least two binary amplitude masks are generated. A photoresist layer on an optical element substrate is exposed through the first mask and then etched. The process is then repeated for the second and subsequent masks to create a multistep configuration. The resulting optical element is highly efficient.

Abstract: A wobble correction lens for a raster output scanner combines a positive cross-scan plano-cylindrical lens, which provides most of the optical power for focusing the light beam to a scan line, with a diffractive surface, which corrects the cross-scan field curvature of the cross-scan plano-cylindrical lens. The diffractive surface will have a multi-level structure (binary diffractive optical surface) which possesses a diffractive phase function that will flatten the cross-scan field curvature of the plano-cylindrical lens.

Abstract: A plurality of binary diffractive optic lenses are formed within a corresponding plurality of recesses in the surface of one substrate. The substrate with the binary diffractive optic lenses in the recess are bonded to another flat substrate. A plurality of individual binary diffractive optic lens cover assemblies are obtained by dicing the two bonded substrates.

Abstract: A Fresnel lens in use for a projector lens comprising a glass plate, a Fresnel lens body integrally formed on one surface of the glass plate, and a reflective layer formed on an annularly grooved surface of the lens body. The present invention provides a Fresnel lens, fabricated with a low cost, having sufficient hardness as a document support and free from any of ghost images or image distortions when used in a projector.

Abstract: An image display apparatus comprises an image projection system having a projecting optical system, and a screen for displaying an image by receiving the image light deflected by a mirror system. The screen has a plurality of sheets one of which contains a group of cylindrical lenses which act as light transmitting areas and light blocking areas arranged on an image light exit plane along the direction of arrangement of the cylindrical lenses. The screen arrangement is capable of blocking undesirable reflected light.

Abstract: The present invention relates to a projection lens system well-fit for baking integrated circuit patterns onto silicon wafers using a light source having wavelengths ranging from an ultraviolet wavelength zone to a vacuum ultraviolet wavelength zone. This projection lens system is characterized by comprising a plurality of lens elements including a Fresnel lens element having negative dispersion characteristics, said Fresnel lens being located at a position lying somewhere in said projection lens system with the exception of the pupil thereof and satisfying the following condition:2h.sub.MAX /3.ltoreq.h.Here h.sub.MAX is the maximum height of a marginal ray in said projection lens system, and h is the height of a marginal ray at the position of said Fresnel lens.

Abstract: An image projection apparatus including a projection lens system projecting an image of a transparent original onto an image receiving surface with a variable magnification and an illumination system illuminating the original. The projection lens system includes a plurality of projection lenses of different magnifications in an interchangeable manner or a zoom lens. The illumination system including a light source unit, a divergent lens unit and a convergent aspherical lens unit so that Kohler illumination can be realized in any magnification. A refracting power of the convergent aspherical lens unit becomes smaller than a spherical lens unit with an increase in a distance from an optical axis. The convergent aspherical lens unit may be includes a Fresnel lens.

Abstract: A confocal microscope comprises a focusing lens for focusing a light source onto a pin hole. The use of the lens for this purpose, when used within a confocal microscope apparatus, greatly reduces image artifacts and creates an increased transfer efficiently between the light source and the sample.

Abstract: A high-efficiency, diffractive optical element having at least one surface including multilevel steps, the steps determined by calculating equiphase boundaries utilizing a disclosed equation and algorithm. The optical element can be adapted to correct for chromatic and/or spherical aberration, and can be used in UV lithographic apparatus.

Abstract: A transmission grating is used to reduce chromatic aberration in a Fresnel lens, wherein the lens chromatic dispersion is offset and substantially canceled by the grating's diffraction-induced dispersion. The grating comprises a Fresnel-type pattern of microscopic facets molded directly into the lens surface. The facets would typically have a profile height of around 4.multidot.10.sup.-5 inch and a profile width of at least 10.sup.-3 inch. In its primary intended application, the invention would function to improve the optical performance of a Fresnel lens used to concentrate direct sunlight.

Abstract: An optical system, that includes a light source having sufficient coherency to provide a predominate operating wavelength and a diffraction grating lens system to focus the light from the light source to an image point on the optical axis of the optical system, provides for change of position of the image point along the optical axis over a wide focusing range with suppression of generated aberration. In particular, the optical system comprises a light source both movable in the direction of the optical axis and capable of variation in wavelength and a diffraction grating lens system that condenses the beam from the light source onto an image point on and along the optical axis, which system is effective in cancelling out aberration generated due to movement of the light source.

Abstract: A optical lens is disclosed which is capable of correcting for imaging system characteristics such as field curvature and spherical aberration. The corrective lens comprises a single optic device and imparts no additional power into the optical system. In particular, the corrective lens comprises a plano-based device (either plano-concave or plano-convex) including a series of stepped zones where the steps are formed to be parallel/perpendicular to the plano surface of the device. The stepped profile of the corrective lens is determined to approximate a lens curvature R which will impart a curvature to the wavefront passing therethrough to essentially cancel selected inherent imaging system aberrations. In particular, a corrective lens of the present invention may be utilized to correct for field curvature, spherical aberration, or both. The corrective lens of the present invention may be formed to be either transparent or reflective, depending upon system requirements.

Abstract: A fresnel lens in which each of the facets is so dimensioned and configured that the distance between the facet and a focal point of the lens is (n+k) .lambda. where n is an integer, .lambda. is the wavelength of the radiation passing through the lens, and k is a fraction between 0 and 1 which is substantially constant for any facet over the entire face of the lens. Preferably the lens comprises a plurality of zones, each comprising a number of facets, the integer n being constant for each facet of each said zone, but being different for facets of different zones.

Abstract: In one embodiment, a three-element biocular eyepiece system 40 having a first optical element 42 with at least one diffractive surface 44, a second optical element 48 having a refracting convex surface 50 and a refracting concave surface b 52 is provided. A third optical element 54 having a refracting convex surface 56 and a refracting convex surface 58 is also employed. In another embodiment, a four-element biocular system 60 is disclosed as having an optical element 62 having a refracting concave surface 64 and a refracting convex surface 66, a refractive-diffractive hybrid optical element 68 having a diffractive surface 70 and a refracting convex surface 72, an optical element 74 having a refracting convex surface 76 and a refracting concave surface 78, and an optical element 80 having a refracting concave surface 82 and a refracting convex surface 84. The diffractive surfaces 44 and 70 have a kinoform profile 102 a-d or approximated kinoform profiles 112a-d and 122a-d.

Abstract: An optical element for producing a collimated output beam having a uniform intensity profile from a highly divergent input beam having a Gaussian intensity profile, the optical element consisting of a single convex-plano lens having a diffractive element etched into the plano side of the single lens in accordance with binary optics technology, the diffraction element being configured to complete collimation of the input beam directed at the convex side of the single lens while at the same time redistributing the input beam to produce a uniform intensity output beam.

Abstract: A back projection type screen having a screen portion to be disposed at a position whereat an image projected from image projector means is formed, the screen portion being formed by at least one transparent sheet, the screen portion having a vertical direction and a horizontal direction in parallel to the surface of the transparent sheet, and a light diffusing portion formed on the light beam incidence side surface of the transparent sheet which is next to the light beam incidence side of the screen portion, the light diffusing portion transmitting an incident light therethrough and also diffusing reflected light in the vertical direction and the horizontal direction. The specification also discloses an image display apparatus using such screen.

Abstract: A reflective-type photoelectric switch projects emitted light from a light-emitting element toward a detection zone by a light-projecting optical system, and guides reflected light from an object to be detected in the detection zone to a light-receiving element by a light-receiving optical system. A special optical element is used in part of at least one of the two optical systems. The optical element functions to diverge light in a direction parallel to a plane containing the optic axes of the light-emitting and light-receiving elements, and condense light in a direction perpendicular to the same plane. As a result, it is possible to detect, with excellent sensitivity, both an object which is far from the switch and an object very near the switch.

Abstract: A method of patterning a photoresist layer to provide an aperture having retrograde sidewalls is described. Illumination may be through a conical prism arrangement or a conical reflecting mirror and cylindrical mirror arrangement. The method includes the step of directing energy towards a mask which selectively exposes portions of a photoresist layer disposed on the substrate. The energy is directed to the mask at an oblique angle with respect to the normal to the surface of the substrate. The underlying photoresist layer is obliquely sensitized by the obliquely directed illumination. The portions of the layer which are obliquely sensitized are removed leaving behind an aperture having retrograde sidewalls. The retrograde sidewalls are a preferred photoresist profile for easy and reliable lift-off of deposited material from the semiconductor substrate.

Abstract: A double directional image development HUD includes a combiner having individual spectral distributions perfectly separated from each other, wherein the image displayed on an LCDU is formed using green light with a sharp spectral distribution and using another color light with a different wavelength, and wherein light beams projected from the LCDU onto a combiner are perfectly divided into two beams, i.e., a reflection light beam and a transmission light beam both of which are perfectly separated from each other, thereby obtaining a clear projected image to be observed by the observers inside and outside the combiner without any contamination.

Abstract: A grating lens is disclosed in which diffraction efficiency varies in the focusing direction of light on a surface of the lens. Also disclosed is a focusing grating coupler in which the diffraction efficiency of a grating formed on an optical waveguide, which is formed on a substrate, varies in the focusing direction of light.

Abstract: An optical element having a substrate and a composite grating pattern formed thereon. The pattern is constituted with two different kinds of grating patterns superimposed on the substrate. When one of the two kinds of grating patterns is formed in a Fresnel lens pattern, a light focusing or collimating function (i.e. a lens function) is implemented. When the other pattern is formed in an equally separated linear grating pattern, the optical element develops the lens function and a function to diffract lights through the linear grating. When one of the two kinds of grating patterns is formed in a Fresnel lens pattern and the other pattern is implemented in an unequally separated linear grating pattern, a lens function to focus lights onto a point and a cylindrical lens function to focus lights in a linear contour are obtained. Consequently, when parallel lights are incident to the optical element, there occurs astigmatism.

Abstract: A bifocal lens of the Cohen lens design utilizing phase zone plate optics and a facet depth of one-half wavelength of the design wavelength, where the primary focal points are at two orders, specifically the 0.sup.th and 1.sup.st orders, and the brightness at each primary focal point is equal at about 0.40.

Abstract: An orbital debris processor includes a square shaped central lens connected to four square shaped satellite lenses. All of the lenses have substantially the same focal length. The lenses are disposed to cause columnated light, parallel to respective axes thereof, to be focussed a substantially a single point. When the debris procesor is oriented to cause solar radiation to be parallel to the axis of the central lens, reflectors reflect solar radiation to the satellite lenses parallel to respective axes thereof. When a metal object is positioned at the point, it is locally melted and this enables a cut to be made. These cut pieces can be used by the processor or stored in a bin.

Abstract: An optical scanning device comprising a light source which emits a luminous flux for irradiating a scanning surface and comprises a semiconductor laser element and an anamorphic ellipsoidal Fresnel lens. The device further comprises a rotary polygon mirror having reflection surfaces for deflecting the luminous flux emitted from the light source. The device further comprises an image forming optical system disposed between the polygon mirror and the scanning surface for forming an optical spot image from the luminous flux on the scanning surface. The optical spot is arranged to scan the scanning surface in a horizontal scanning direction and a vertical scanning direction. The optical system is so arranged that the reflection surface and the scanning surface are positioned at conjugate points with respect to each other for the luminous flux with regard to the vertical scanning direction.

Abstract: A multicolor display lamp used as a display element of a dot-matrix display device. comprises light sources having different emitting colors arranged in four areas of a square case so that their optical axes are parallel to each other, and an optical system arranged frontwardly thereof so as to individually extend emitting rays of the light source.

Abstract: A multifocal ophthalmic lens has diffractive power produced by a plurality of concentric zones. The zones have radii that meet the condition R.sub.0.sup.2 <R.sub.1.sup.2 -R.sub.0.sup.2 where R.sub.0 is the radius of the central zone and R.sub.1 is the radius of the first annular zone.

Abstract: Alignment difficulties in optical computing arrangements are overcome by integrating the optical components on a single substrate and arranging the elements in a manner that causes them to interact with one another to perform the desired function. The substrate has one or two major surfaces and the elements are grown or fabricated on those surfaces using conventional integrated circuit manufacturing techniques. Most advantageously, the position-sensitive optical devices are manufactured on one side. Reflective planar optical devices are obtained by applying a reflective layer over the fabricated planar optical devices.

Abstract: There is disclosed a diffractive optical element and a method to produce same wherein the element comprises a base and at least one phase zone comprising an arbitrary multiplicity M of steps of generally identical step height, wherein M is not a power of 2. The method includes the steps of defining a basic depth unit equivalent to a zone height divided by M, defining a depth sequence of N depths wherein N is the smallest integer greater than log.sub.2 M such that each of the M steps can be produced by at least one linear combination of the N depths, defining N masks herein each mask enables the optical element to be processed to one of the N depths and wherein for each mask, the steps to be processed are those which have the one of the N depths in its linear combination and serially utilizing each of the N masks for processing of the optical element.

Abstract: This invention relates to a replica plate having a transparent plastic substrate and a photo-cured resin, and a projection type television using the replica plate. An adhesive layer comprising an acrylic or methacrylic compound is provided between a transparent plastic plate and a replica-forming photo-curable resin, whereby it is possible to enhance the adhesion between the surface of the transparent plastic plate and the photo-cured resin, and to produce a replica plate having excellent optical characteristics, good replicating properties and high reliability. The adhesive layer can be provided (1) by coating a layer containing the acrylic or methacrylic compound on the plastic plate, the compound infiltrating into the plate, or (2) by incorporating the acrylic or methacrylic compound into the photo-curable resin, the compound infiltrating therefrom into the plate; in this latter technique, the plate coated with the resin should be heated.

Abstract: An optical system is provided for magnifying the image on a television receiver to viewers in a room. The system is comprised of a plano-convex lens disposed in front of the viewing screen of a television set and a fresnel lens interposed between the viewing screen and the plano-convex lens. The fresnel lens has a smooth surface and an opposite surface configured with a pattern of concentric dioptric ridges facing the plano-convex lens. The magnification achieved by the combination of lenses allows viewers within the room to view a magnified image on the television receiver. Preferably, the planar surface of the plano-convex lens and the smooth surface of said fresnel lens are both disposed to face the television screen so that the television screen can be viewed without significant aberrations or distortion from a wide range of viewing distances.

Abstract: A holder for adjustably positioning a flat-sheet magnifier proximate a visual display terminal comprises a mounting for retaining the magnifier and a support for extensibly positioning the mounting in a predetermined, spaced-apart relationship with the terminal. Disclosed are particular arrangements of mounts and supports including slidable members, telescopic legs and pivoting, scissor-action legs, all of which provide for the positioning of a magnifier proximate a display screen.

Abstract: An illumination system for use in an image projection apparatus, having a light source assembly which includes a lamp and a concave reflector for producing convergent light, and an illumination lens group which includes, in order from the light source assembly side, a first lens unit of a negative power, a second lens unit of a positive power movable along the optical axis and a third lens unit of a positive power. The illumination lens group fulfills the following equation,1+2<0where 1 and 2 represent the powers of said first and second lens units, respectively.