Abstract: An optical device for a system for the presentation of collimated images by a non-plane mirror, which makes it possible to present a user with an image corrected of distortion due to a non-plane mirror and exhibiting good resolution. To do this, the device includes a Mangin type mirror whose optical characteristics ensure good image quality of correction of off-centering distortion and good image sharpness. The Mangin type mirror has a reflecting surface and a layer of refracting material defining a refracting surface. One surface may be spherical, and the other aspherical. The surfaces may also be aspherical. One aspherical surface may be a paraboloid, an ellipsoid, or a torus. The refracting material can exhibit an optical index varying according to the position on the surface of the mirror. The device may be applied in particular to a system for the presentation of collimated images by a spherical mirror inclined with respect to the direction from which it is observed.

Abstract: A helmet mounted display for mounting on a helmet includes a supporting structure removably mounted at at least one point to the helmet, a visor, mounted on the structure, and at least one optical system, for projecting an image on the visor from the side of the pilot's head. The at least one optical system is side mounted on the supporting structure, and includes a source of light and a digital reflective device or a reflective addressing device. The digital reflective device contains a plurality of micromirrors for deflecting the light source in a pixelated manner via a plurality of pixels. The deflection of the micromirror can be controlled as a function of time.

Abstract: A polarizer is made from pairs of polarizing beam splitting cubes. In every pair, a first cube transmits P-polarized light and reflects S-polarized light. A retarder rotates the transmitted light to become S-polarized. A second cube receives only the reflected light, and redirects it in the direction of the transmitted light. A polarizing filter filters the reflected light, but not the rotated light. Exposing the retarder improves the transmission throughput of the overall polarizer. A stop at the side of the second cube blocks light from entering the first cube of an adjacent pair.

Abstract: An optical element is made of a material that is transparent to a selected spectral band and has an embedded optical layer system. The optical layer system has a first optical system in a first plane which at least predominately reflects light from a first band in the spectral band, and at least predominately transmits light from a second band in the spectral band. A second optical system is also provided in a second plane that intersects the first plane in a central area of the body of the optical element. The second system predominately transmits light from the first band and predominately reflects light from the second band. Optical paths are defined in the optical element between first and second entrances and exits for the light of the first and second bands.

Abstract: A zoom lens system that is free from parallax, is compact, and offers excellent optical performance has, from the object side, a positive first lens unit, a negative second lens unit, a positive third lens unit, and a negative fourth lens unit. The zoom lens system has a half-prism between the second lens unit and the third lens unit so that a light beam having passed through the second lens unit is split by reflection.

Abstract: A virtual image display system is provided which is made thinner through the use of an immersed beam splitter, and in one embodiment, total internal reflection. The display system includes an imaging surface on which a source object is formed, a first optical element having a reflective function and a magnification function, a second optical element having a magnification function and an immersed beam splitting element positioned between the first and second optical elements, the immersed beam splitting element including a beam splitter surrounded by an optically transparent material having a refractive index greater than air. An illumination source projects the source object formed at the imaging surface through the optically transparent material to the beam splitter. The beam splitter reflects the projected source object to the first optical element. The first optical element magnifies the projected source object and reflects a magnified virtual image of the projected source object to the beam splitter.

Abstract: A beam path expander for a large-area laser projection display system having a small compacted optical system includes an incidence plane forming an anti-reflection plane to admit light having a specific wavelength into a medium without reflection, a first total reflection plane that is cut into the beam path expander at a total reflection angle determined by the refractive index of the medium for total-reflecting the light admitted from the incidence plane in the medium, a second total reflection plane that is cut into the beam path expander at a total reflection angle for total-reflecting the light reflected from the first total reflection plane at the total reflection angle in the medium, n third total reflection plane(s) (n=0, 1, 2, . . .

Abstract: A device for the detection of a continuous field of view or an arrangement of non-contiguous field of view sectors by means of an image resolving detector is provided such that the field of view sectors can be imaged quickly, one after the other, on the total area of the detector. To this end, a first imaging optical system ist provided, in the pupil of which a plurality of pupil areas is formed, each of which images a field of view sector on a common image plane area. A beam deflecting, microoptical beam deflecting element is arranged in the common image plane area. A second imaging optical system is arranged to image the microoptical beam deflecting element on the image resolving detector. The microoptical beam deflecting element is controllable such that it successively deflects beams from different pupil areas on the second imaging optical system.

Abstract: For providing a compact, light, and cheap image pickup apparatus capable of attaining both a stereoscopic image and a high-definition plane image by itself, a changeover optical unit is provided with both a function to attain a stereoscopic image by guiding beams captured through objective lenses to respective CCDs and a function to attain a plane image by splitting the beam captured through the objective lens into two beams and guiding the two beams to the CCDs whereby the stereoscopic image and the high-definition plane image can be attained by proper changeover between these functions.

Abstract: An apparatus for splitting a light beam into two sub-beams is formed of a stationary light source for generating a light beam, of a first polarization converter and of a deflection unit rotating around the optical axis in which two sub-beams are generated from the light beam. The deflection unit contains a polarization beam splitter, a following, second polarization converter and a reflector that is preferably designed as a prism. An automatic correction of positional offsets of the sub-beams is implemented in the deflection unit since the polarization beam splitter or the deflection unit is tilted and/or the lenses are shifted with adjustment drives. The positional offsets of the sub-beams are measured in their focus plane, and corresponding correction values are transmitted with a transformer to the adjustment drives in the rotating deflection unit.

Abstract: The invention is directed to a high-resolution high-apertured objective which includes an object plane (1); a first lens group (LG1); a second lens group (LG2) downstream of the first lens group; a beamsplitter (17, 18, 22, P) downstream of the second lens group; a concave mirror (21); a system diaphragm (A) interposed between the beamsplitter and the concave mirror; a third lens group (LG3); the objective defining an image plane and being configured to provide a reduction scale (.beta.) in the range of -0.4 to -0.15 and an image side numerical aperture greater than 0.5. The first and second lens groups (LG1, LG2) are configured to conjointly reduce the sine of the marginal ray angle. The reduction can be up to 40%. Preferably, the second lens group (LG2) can be configured to alone reduce the sine of the marginal ray angle. It is preferable that the sine of the marginal ray angle (sin R.sub.LG1) after the first lens group (LG1) is not less than the sine of the marginal ray angle (sin R.sub.

Abstract: An optical system is disclosed for improving the brightness symmetry of a beam emitted from a laser diode where the beam has a large width and a narrow height. The optical system includes a tilt plate for displacing one half of the width of the beam downwardly. A first beam steering prism functions to tilt the remaining, second half of the beam width in a plane parallel to the width dimension so that the second half travels towards the first half. A second beam steering prism is provided to tilt the second half of the beam so that its propagation axis is parallel to the propagation axis of the first half and wherein the second half is stacked above the first half. The optical system functions to improve the brightness symmetry of the beam by a factor of about five. The corrected beam can be used to improve the performance of a solid state laser which is end pumped by a broad area laser diode or a laser diode bar.

Abstract: The temperature coefficient of refractive index in each lens constituting an imaging lens is controlled such that the amount of change in the imaging position due to change in the imaging lens upon temperature alleviates the positional deviation between the imaging position and the light-receiving surface caused by members other than the imaging lens, thereby preventing the read-out accuracy from deteriorating. The amount of change in the imaging position caused by change in the refractive index of lenses upon change in temperature is adjusted so as to alleviate the positional deviation between the imaging position and light-receiving surface due to the thermal expansion of the member unitedly holding the light source, lenses, and receiving optics.

Abstract: An image display apparatus which enables observation of a clear image at a wide field angle with substantially no reduction in the brightness of the image, and which is extremely small in size and light in weight and hence unlikely to cause the observer to be fatigued. The apparatus includes an image display device (6) and an ocular optical system (9) for leading an image of the display device (6) to an observer's eyeball (1). The ocular optical system (9) has a first optical element (7) and a second optical element (8). The first optical element (7) has three surfaces, and a space formed by the surfaces is filled with a medium having a refractive index larger than 1.

Abstract: An optical beam splitter has an imaging lens assembly with a single optical axis and reflectors located on the image side of the lens to produce a number of real images of an object imaged by the lens. The imaging lens assembly is designed to image the real image formed by a camera lens assembly on the optical axis where the camera lens assembly has an exit pupil a known distance on the object side of this real image. The imaging lens assembly is then adapted to image this exit pupil of the camera lens to an aperture plane adjacent the reflectors. The optical beam splitter is described in particular in an application in an electronic high speed camera wherein multiple images of an object are formed for high speed photography.

Abstract: An optical system for illuminating a multi-element spatial light modulator from a multi-emitter laser array such that each element of the modulator sees light from all emitters targets the light onto the two or more rows of elements, without putting light into the gap between the rows, and without putting light in the spaces between the elements. The element illumination may match a complex shape of the elements. A beamsplitter/staggerer is adapted to split the line of laser light into plural parallel lines of light, and to split the parallel lines of light into regions such that substantially all of the light from the illumination system falls onto the elements of the rows without impinging between the rows of elements or between the elements in the rows.

Abstract: Illumination light having passed a pattern formed on a first surface enters a beam splitter directly or through a refracting system. On this occasion, inside the beam splitter, at least part of the illumination light having passed through an entrance surface is transmitted or reflected by a direction changing surface and then passes through an exit/entrance surface. Subsequently, the illumination light first leaving the beam splitter is reflected by a reflective surface of a concave mirror and then again enters the beam splitter. On this occasion, inside the beam splitter, at least part of the illumination light having passed through the exit/entrance surface is reflected or transmitted by the direction changing surface then to pass through an exit surface. The illumination light thus again leaving the beam splitter is projected directly or through a refracting system onto a second surface to form an image of the pattern thereon.

Abstract: A polarizing beam splitter for dividing a return light beam reflected by a magneto-optical record medium into two light beams polarized in mutually orthogonal directions, including a main body made of a birefringent crystal and having an incident surface upon which the return light beam is made incident and a reflection surface, and a reflecting member provided on the reflection surface of the main body and formed by a metal film or a stack of dielectric material films. Upon refraction by the incident surface of the main body, the incident light beam is split into ordinary and extraordinary light beams, which are then reflected by the reflection surface of the main body. An optic axis of the main body is set to be parallel with the reflection surface, the ordinary and extraordinary light beams are reflected as they are and emanate from the polarizing beam splitter.

Abstract: An optical splitter arrangement is provided for accepting a light from at least one input and providing multiple light outputs of four or more, a light intensity of the outputs differing from one another no more than two dB, and a light intensity of the cumulative outputs differing no more than three dB from the light intensity of the input.

Abstract: An assembly for producing a visual display includes a light-reflecting type spatial light modulator and an illumination arrangement for providing a particular source of light. The spatial light modulator has a light reflecting surface cooperating with a light modulating medium switchable between different states so as to act on light in ways which form an overall pattern of reflected, modulated light. The spatial light modulator also has an arrangement for switching the modulating medium between the different states in a controlled way so as to form the overall pattern. The overall assembly further includes an optics arrangement having a first member defining a light reflecting surface.

Abstract: A planar parallel plate direct vision prism including two glasses for dispersing light as a function of color is disclosed. Also disclosed is an optical system which includes a first optical assembly having two planar parallel plate direct vision prisms for dispersing light as a function of color. The degree and orientation of the light dispersed is controlled by rotating the two prisms of the first assembly in relation to each other and together in unison. A fiber optic bundle transmits the dispersed light and a second optical assembly having two planar parallel plate direct vision prisms recombines the dispersed light emerging from the fiber optic bundle. The degree and orientation of the light recombined is controlled by rotating the prisms of the second optical assembly in relation to each other and together in unison.

Abstract: First polarizing beam splitters have respective first polarization separating surfaces arranged perpendicularly to each other. Each of the first polarization separating surfaces transmits the P-polarization component of a light beam emitted from a light source and reflects its S-polarization component. Each of first light beam reflecting elements reflects the S-polarization component reflected by the first polarization separating surface and a light beam directly inputted from the light source. Second polarizing beam splitters have respective second polarization separating surfaces, each of which transmits the P-polarization component of the light beam inputted from the light source and reflected by the first light beam reflecting element and reflects the S-polarization component. Each of second light beam reflecting elements reflects toward a liquid crystal display device the P-polarization component transmitted from the second polarization separating surface.

Abstract: On one end side of a converging rod lens are provided a first and second input optical fibers and a first and second output optical fibers. On the other end side of the converging rod lens is provided a reflecting mirror. Between the converging lens and the first and second input and output optical fibers is provided a birefringent element for resolving a ray which passes therethrough into an ordinary ray and an extraordinary ray. In the optical paths of the first and second output optical fibers between the converging rod lens and birefringent element is placed a compensator for rotating 45 degrees the plane of polarization of a ray which passes therethrough. The reflecting mirror reflects incident rays from the first and second input optical fibers to the first and second output optical fibers. Between the converging rod lens and the reflecting mirror is provided a magneto-optical element for rotating 22.5 degrees the plane of polarization of a ray which passes therethrough.

Abstract: This polarization beamsplitter with a substrate-mode holographic structure is used to separate the s-polarization beam with p-polarization, and guide two separated beams at directions parallel to each other. The element consists of a pair of substrate-mode gratings with a specific designed diffraction angle and index modulation on a dielectric substrate. Through the input grating the normally incident beam with one polarization has zero diffraction efficiency and directly pass through the substrate; the beam with another polarization is diffracted at an angle exceeding the critical angle, then propagates through the substrate with total internal reflection to the output grating, and normally coupled out of the element. Thus, the beams with two different polarizations are separated, and two beams propagates at direction parallel to each other.

Abstract: Optical magnifying apparatus comprises an objective lens (11) from which light is directed to a beam splitting mirror (12). A portion of the light passes through the beam splitting mirror to a first concave mirror (13) and is reflected back via the beam splitting mirror through a viewing lens (5) to a first eye (16) of an observer. The remainder of the light is reflected by the beam splitting mirror to a second concave mirror (17) from which it is reflected back via the beam splitting mirror through the viewing lens to a second eye (19) of the observer. Focussed first and second images (14, 18) of an object (10) are produced respectively on the surfaces of the first and second concave mirrors. The optical axes of the concave mirrors are relatively offset such that the relayed pupils of the mirrors are separated horizontally by a distance approximately equal to the average interpupillary spacing of an observer.

Abstract: A helmet mounted display system comprising an eyepiece (3) through which a wearer of the helmet directly views a forward scene (13). The eyepiece also serves to combine an intensified image of the forward scene with the wearer's direct view of the scene. The intensified image is produced by an optical arrangement including an image intensifier (6) from which light is passed to the eyepiece via a prism (2). The prism serves to compensate for orientation of the intensified image in other parts of the optical arrangement so that the intensified image is in the same orientation as the wearer's direct view of the forward scene. In addition the prism allows the various components in the system light path to conform to the profile of the helmet thereby making the helmet more comfortable for a wearer.

Abstract: An optical component consists of two or more plane-parallel windows with, respectively, two or more partially reflective surfaces. Each partially reflective surface splits off part of an original beam and produces another redirected beam. The redirected beam undergoes further redirection and attenuation by multiple reflections. Each even-numbered reflection produces a beam deviated from the original's beam direction by an even multiple of the angle between the windows. Thus, for a pair of windows a series of beams are produced that are in a straight line and are equally spaced.

Abstract: An optical power splitter for the distribution of high-power light energy has a plurality of prisms arranged about a central axis to form a central channel. The input faces of the prisms are in a common plane which is substantially perpendicular to the central axis. A beam of light which is substantially coaxial to the central axis is incident on the prisms and at least partially strikes a surface area of each prism input face. The incident beam also partially passes through the central channel.

Abstract: In accordance with the teachings of the present invention, a system and method are provided for steering a beam of optical radiation. The system includes a dividing telescope microlens array for receiving a beam of optical radiation directed along a first path and dividing the beam into a plurality of divided beam columns. A steering microlens array collectively redirects each of the divided beams along a second path. The system further includes a compensation lens for compensating for phase differences which may otherwise exist among the redirected divided beam columns. The redirected divided beams are then combined by way of a combining microlens array to provide a recombined far-field beam of optical radiation directed along the second path.

Abstract: A laser beam dividing apparatus (10) having a first beam splitter (14) with an aperture (16) therein positioned in the path of a laser beam (12) such that a portion of the laser beam (12) passes through the aperture (16) onto a second beam splitter (20) and a portion of the laser beam (12) impinges upon the first beam splitter (14). Both the first beam splitter (14) and the second beam splitter (20) are, optionally, made from a dichroic material such that a green component (24) of the laser beam (12) is reflected therefrom and a yellow component (26) is refracted therethrough. The first beam splitter (14) and the second beam splitter (20) further each have a plurality of facets (22) such that the components (24, 26) are reflected and refracted in a number equaling the number of facets (22).

Abstract: A system for performing laser welding comprises an optical lens for receiving an incoming laser beam and for dividing the laser beam into a number of different beam segments. The top surface is defined by a number of different surfaces for respectively dividing the laser beam into the number of beam segments. The optical lens has a convex bottom surface for focusing and directing the beam segments onto a respective number of welding locations. Preferably, the laser welding system is used to simultaneously perform five welds on an improved spacer grid assembly which has a cylindrical member located at each intersection of the spacer strips. By simultaneously performing the five requisite welds, the welding time is significantly reduced. Also, the welding process is simplified since the system only has to be in one position to perform all of the welds at each intersection.

Abstract: An optical sight typically used in cooperation with a weapon is provided to include a light tube, that in turn further is provided with a blade member mounted to the light tube that includes a concave surface of mirror image reflective qualities directing light into the light tube for enhanced optical illumination through the sight arrangement.

Abstract: An optical fiber amplifier suited for use in optical fiber transmission systems includes a plurality of optical passive components. The optical passive components are integrated into an assembly including a birefringent crystal, a first lens, a magneto-optic crystal, an optical filter, and a second lens, all of which are axially aligned in this order, with a half-wave plate interposed between the birefringent crystal and the first lens. The birefringent crystal is opposed to end faces of first and second optical fibers and separates incident light into two linearly polarized light beams having respective polarized light planes generally perpendicular to each other. The half-wave plate allows light emitted from the second optical fiber to pass therethrough and rotates a polarized light plane of incident light. The first lens converts incident light into a generally collimated ray, and the magneto-optic crystal rotates a polarized light plane of incident light by an angle of .pi./8+Nn/4 (N=0, 1, 2, . . .

Abstract: Method and apparatus for separating a mixed frequency light beam, particularly a laser light beam, into its different frequency components by impinging it on a first surface of an optical slab which reflects one component but transmits another, and re-directing the reflected component via a roof prism to a second surface of the slab which is adjacent to and positioned 90.degree. to the first surface, to obtain a reflected beam which is co-directional with the mixed beam, but stripped of the transmitted component.

Abstract: In the process and by means of the apparatus, several radiation sources (1) arranged in a row, whose emitted radiation intensity distribution is not rotationally symmetrical, are imaged by means of a first, noncentrically imaging functional element (5), then each beam bundle (9) is rotated by means of a beam-rotating element (7), and the beam components of the rotated beam bundles (9) not imaged by the first functional element (5) are imaged by means of a second, noncentrically imaging functional element (11). The functional elements (5, 11) and their locations are chosen so that parallel beam bundles (9) are produced which are focused with a spherical lens (15) into a spatial zone (3). The apparatus according to this invention provides in a simple way a good focusing ability for several individual beams.

Abstract: In a focus detecting optical system wherein a beam transmitted through an objective optical system is divided to thereby effect focus detection, a beam reflected by an optical disk is transmitted through an objective lens and a half mirror and is condensed by a condensing lens. The light beam from this condensing lens is divided by a dividing member comprising a pair of obliquely disposed plane parallel plates and becomes divided beams parallel to each other, and these divided beams arrive at a four-division detector. The dividing lines of this detector are on the meridional plane of the objective optical system.

Abstract: First and second beam splitters are arranged on the optical path of a light beam emerging from a recording surface, and such that the phases and amplitudes of the respective polarized light components of a light beam incident thereon are changed to equal extends. As a result of this arrangement, the state of polarization beam of the light beam emerging from the recording surface is maintained when a light beam is outputted through the two beam splitters. Stable reproduction signals and servo control signals for focusing, tracking, and the like can be reliably supplied by utilizing an apparatus of this invention.

Abstract: A very wide band beam splitter for operation in the range between deep ultraviolet of 190 nanometers and into infrared is comprised of uncoated transparent material only 0.10 to 0.15 mm. in thickness.

Abstract: An optical imaging device for projecting an image in a strip area, comprising a reflecting plate having a plurality of pairs of reflecting surfaces arranged on a flat surface and forming an array in a first direction parallel to a long direction of a strip image, and at least one cylindrical focusing lens or mirror having a focusing power directed only to a second direction perpendicular to the first direction. The pair of reflecting surfaces is composed of two flat surfaces which cross at about a .pi./2 radian, and the crossing line of two adjacent reflecting surfaces is perpendicular to the first direction. The reflecting plate projects the image component in parallel to the first direction and the cylindrical focusing lens or mirror projects an image component perpendicular to the first direction. The resolving power in the first direction of the obtained image is determined by the pitch length of the pair of reflecting surfaces.

Abstract: An imaging device for processing an optical image in the visible and/or infra-red wavelength bands. An optical image receiving area is divided into four segments and each segment is associated with an optical sensing means in the form of a semiconductor chip comprising a plurality of pixels. Each segment also includes a reflection means for reflecting the particular optical image to the associated optical sensing means. The reflecting means preferably takes the form of a reflecting surface within a cube comprising two prisms. The reflecting surface may be fully reflecting dichroic or holographic. A further optical sensing means in the form of a semiconductor chip is employed to the rear of the image receiving areas and is positioned to sense for small separate segments of the four guarter segments in the center of the overall optical image. All the separate received optical images are processed electronically to produce a composite image.