Abstract: A projection exposure system for microlithography includes an illuminating system (2), a reflective reticle (5) and reduction objectives (71, 72). In the reduction objective (71, 72), a first beam splitter cube (3) is provided which superposes the illuminating beam path (100) and the imaging beam path (200). In order to obtain an almost telecentric entry at the reticle, optical elements (71) are provided between beam splitter cube (3) and the reflective reticle (5). Advantageously, the reduction objective is a catadioptric objective having a beam splitter cube (3) whose fourth unused side can be used for coupling in light. The illuminating beam path (100) can also be coupled in with a non-parallel beam splitter plate. The illuminating beam path is refractively corrected in passthrough to compensate for aberrations via the special configuration of the rear side of the beam splitter plate.

Abstract: A double-pass projection display system with separate polarizers and analyzers. One embodiment of the invention includes an input polarizer, a color separation/recombination device, and a number of image producing sections. The input polarizer receives unpolarized white light and polarizes this light. The color separation/recombination device receives the polarized white light and separates this light into a number of component color bands. The color separation/recombination device then supplies a component color band to each image producing sections. Each section includes a spatial light modulator and an output analyzer. The spatial light modulator modulates the color band that the image producing section receives from the color separation/recombination device. The output analyzer then (1) discards the light, in the modulated band, that has a first polarization state, and (2) directs the light, in the modulated band, that has a second polarization state to the color separation/recombination device.

Abstract: A miniature display system has light source, display panel, polarized beam reflector film, curved reflector, and quarter wave film. The light source supplies light polarized in a first direction. The light from the light source reflects off the polarized beam reflector film and impinges the display panel. The polarized beam reflector film is configured to reflect light polarized in the first direction but pass the light polarized in a second direction orthogonal to the first direction. The display panel produces images on its surface (“display surface”). The light hitting the display panel is reflected orthogonally (polarized in a second direction) and bearing the image, thus bearing a pattern. The modulated light passes through the polarized beam reflector film and is reflected on a curved reflector. The quarter wave film is disposed between the polarized beam reflector film and the curved reflector.

Abstract: The optical pickup includes a two-wavelength laser diode having two light sources that emit a laser beam for the DVD and a laser beam for the CD, a light-receiving member, and a beam splitter. The beam splitter is provided with a wavelength-separating layer composed of a first and a second interfaces and an optical thin plate between the interfaces, having a specific refractive index n2. The first and second interfaces each have a first and a second wavelength selecting films coated thereon, which reflect or permeate the laser beams each by the specific rates, bring the optical axes of the laser beams after having reflected on the first and second interfaces into coincidence, permit the laser beams to go out of the beam splitter, and make the return beams from the optical disks permeate through the wavelength-separating layer to guide them toward the light-receiving member.

Abstract: A linear array of equal intensity optical beams is transformed into a rectangular array of equal intensity optical beams, while the intensity of each beam is kept nearly constant. The transformation is performed using an optical element which has two coatings on the front surface and a reflective coating on the opposing back surface. The front surface is partially coated with a reflective coating and partially coated with an anti-reflective coating. The beams are incident upon the front surface, with some of the beams incident on each of the two different coatings on the front surface. The beams incident on the front surface are specularly reflected. The remaining beams are transmitted through the optical element to the back surface, reflected from the back surface, and transmitted back up through the optical element and exit from the front surface. The exiting beams are thus shifted laterally and transversely to define the desired rectangular array.

Abstract: The method for splitting and reflecting beams in a laser scanning microscope which produces a laser beam (1) comprises the steps of: reflecting a beam from a partially reflecting mirror (2); splitting the laser beam (1) with a splitting device into partial beams (5); causing the partial beams to travel in a plane; directing the partial beams to a sample under investigation; providing the partially reflecting mirror (2) with a constant transmission; placing the partially reflecting mirror between two high reflectivity mirrors (3,4); transmitting the laser beam (1) to one of the high reflectivity mirrors (3); reflecting said beam (1) to the other one of the high reflectivity mirrors (4) with basically equal attenuation; repeatedly transmitting the beam to one of the mirrors; and repeatedly reflecting the beam to the other one of said mirrors (4); arranging the partially reflecting mirror and the high reflectivity mirrors (3,4) relative to each other to cause beams (5) reflected by the partially reflecting mirro

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: A system which is preferably employed in a laser alignment instrument produces up to five orthogonal beams from a single laser diode beam. In one embodiment the optics take advantage of the elliptical shape of the beam from a laser diode which when collimated produces a plurality of orthogonal beams by reflection off a plurality of 45.degree.-angled reflective surfaces intercepting outer portions of the beam. In one preferred embodiment a solid reflective element was four 45.degree.-angled facets to produce four beams from outer portions of a preferably non-elliptical beam, and a fifth orthogonal beam is produced by transmission of a central portion of the beam through the element. The element can be solid glass, or it can be glass or other material with a central hole.

Abstract: An image display apparatus using a modified prism as an ocular optical system, in which unwanted light caused by reflection or transmission at an area outside the effective area of a reflecting or transmitting surface is reduced to provide a favorable image of high resolution, which is free from flare or ghost. The prism member (10), which is used as an ocular optical system, includes a first surface (1) having an action through which a light beam enters the prism member, a second surface (2) having an action by which the light beam is reflected in the prism member, and a third surface (3) having an action through which the light beam exits from the prism member. A black coating (12), which is an antireflection member having a flare- or ghost-preventing action, is provided over a part of a non-effective reflecting area of at least the second surface (2), exclusive of an effective reflecting area (an area reflecting an effective light beam that forms the virtual image).

Abstract: The invention provides an optical device suitable for use with an optical amplifier, for example, in an optical communication system and advantageous in that different functions of a plurality of optical elements are achieved using an optical element of a simple construction and the optical device can be produced in a reduced size at a reduced cost. The optical device includes a tapered prism constructed such that a first face and a second face thereof opposing to each other do not extend in parallel to each other. A dielectric multi-layer film is formed on the first face of the tapered prism positioned on an optical signal inputting side. A reflection film is formed on the second face for reflecting the optical signal inputted to the tapered prism through the first face at least once toward the first face.

Abstract: An optical element useful in optical systems such as liquid crystal optical display devices which is capable of projecting images having a high degree of contrast is provided. The optical element comprises a set of prisms whose coatings are designed to cancel one component of the depolarization in the light the prisms deliver. The other depolarization component is removed by returning the light to the projection lens through the same sequence of color-dividing coatings in reverse order. Hence, the optical element eliminates the depolarization components by employing double-pass propagation of polarized light therethrough.

Abstract: Illuminated instruments in aircraft cockpits often create reflections from the canopy which interfere with the pilots vision. A wedge of optical material positioned adjacent the instrument retracts the light rays such that the canopy reflections are deflected away from the eyes of the pilot.

Abstract: Optical components that are designed to be coupled together in modular fashion to form an optical network. The components are shaped so that a plurality of components can be coupled together to form a light cube. The components are provided with mating means to permit easy coupling. The preferred form of component is a right-angled triangular prism that can be coupled together with a similar prism to form a cube.

Abstract: An optical arrangement includes several separate individual beams that pass through a common focus before a first segmented mirror field and, after reflection by respective separate mirrors of the segmented mirror field, the individual beams are imaged by an objective on one or more workpieces. A second segmented mirror field is arranged between the first segmented mirror field and the object, or at least one beam splitter is arranged after the focus and deflects the individual beams onto at least one segmented mirror field, by which they are reflected back at least nearly identically on themselves.

Abstract: A branching mirror and a transfer mirror receiving a laser beam reflected on the branching mirror and outputting a laser beam in a direction parallel to the laser beam coming into the branching mirror are fixed to and mounted on one mirror holder. The mirror holder is movably provided between a branching position at which the branching mirror is located in a light path of the laser beam and an escaping position at which the branching mirror is located outside the light path of the laser beam, and while the mirror holder is located at the beam branching position, a laser beam from a laser oscillator can be introduced to the branching mirror.

Abstract: Multiple channel optical multiplexing/demultiplexing devices that utilize only a single constant, non-variable wavelength-selective optical interference filter have many advantages. The wavelength-selective optical filter is a conventional fixed wavelength optical interference filter having an angle shift property wherein the wavelength-selectivity changes with changing angles of incidence upon the filter. Because such filters are transparent to a different center wavelength depending on the angle of incidence of a light beam, multiplexing/demultiplexing is achieved by varying the angle of incidence of the light beam upon a single, constant and non-variable optical interference filter. Many different systems can be designed to transmit a light beam at multiple varied angles of incidence upon a single interference filter. Two such exemplary systems utilize a multiple-reflection chamber adapted to transmit a light beam at successively varied angles of incidence upon a single interference filter.

Abstract: A system which is preferably employed in a laser alignment instrument produces up to five orthogonal beams from a single laser diode beam. The optics take advantage of the elliptical shape of the beam from a laser diode to produce a plurality of masked, parallel collimated beams which are then reflected by combinations of 45.degree.-angled and 90.degree.-angled mirrors, some fully reflective and some partially transmissive, to produce the orthogonal beams.

Abstract: A light-diffusing holographic transflector comprising a holographic layer and a transflective layer is disclosed. The transflector is capable under good ambient lighting conditions of illuminating an LCD display element by holographic reflection, and under poor ambient lighting conditions, by the transmission therethrough of internal edge- or back-lighting. The transmission of light is accomplished to form a predetermined visually-perceptible image (e.g., graphics, designs, and logos) by the provision in said transflector of a corresponding pattern of light-transmitting microholes. The light-transmitting microholes are formed preferably by laser ablation or etching.

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: Vehicle body accessories are formed of a transparent plastic material, and having markings defining a repeating pattern of opaque and transparent regions on one side of the transparent plastic material. The markings reduce the amount of light transmitted through the accessory, and give to the accessory an aesthetically pleasing appearance. The accessory can be used as a headlight cover, a tail light cover, a side window protector, a rear window protector, or a hood protector.

Abstract: A scanning optical device that includes a laser source that emits a laser beam; a deflector for deflecting a laser beam to form a scanning beam spot on an image surface; a beam splitter, between the laser source and the deflector, and a sensor positioned in a predetermined position relative to the beam splitter. In particular, the beam splitter includes a reflective area in which the laser beam from the laser source is reflected and a transmitting area that is distinct from the reflective area through which the laser beam is transmitted. One of the reflected laser beam or transmitted laser beam is a main beam to be deflected by the deflector and the other is a monitor beam to be detected by the sensor.

Abstract: Optical beam-splitting system for partitioning the real image of an object into a plurality of partial images onto image receivers arranged with a distance between them, comprising an objective lens and a plurality of optical elements arranged in the ray path behind the objective lens with each optical element comprising at least one reflecting plane deflecting the path of rays, the optical elements respectively intercepting partial luminous fluxes not interfering with each other, the optical elements being positioned outside of the overlapping region of the rays emanating from the extremities of the object and passing through the objective lens and in front of the image plane of the objective lens.

Abstract: A beam shaping device for a laser device is provided. The laser device has a beam with a first beam quality factor M.sub.x.sup.2 in a first direction, and a second beam quality factor M.sub.y.sup.2 in an orthogonal direction. The beam shaping device includes at least one reflecting surface diverting at least a first part of the beam in order to reconfigure at least one of the first and second beam qualities M.sub.x.sup.2 and M.sub.y.sup.2.

Abstract: An optical engine for combining or splitting color light beams, compatible with modern high-speed projection systems, is described. The invention utilizes a unique pentaprism core element, partially bounded by five faces, two each on either side of a plane of bilateral symmetry and one opposite, bisected by the plane of bilateral symmetry. Two of the faces of the pentaprism are coated with dichroic films. Functioning as a light combiner, the pentaprism uses these dichroic surfaces and its geometry to interact with incoming tri-color light beams which, after first passing through appropriately modulated light valves, are selectively transmitted and reflected such that all beams exit, axially aligned, from one side of the pentaprism. Functioning as a light splitter, the pentaprism uses the dichroic surfaces and its geometry to split a white light beam into its component primary colors and pass these colors out of the pentaprism.

Abstract: An image pick-up apparatus (1) which includes a beam splitter (2) for splitting an image into sub-images and several image sensors (3, 4) for picking up the sub-images is provided with a depolarizing element (6) for reducing the linear polarization degree of the light incident on the beam splitter. The electronic image signals of the image sensors (3, 4) are combined so as to form an electronic image signal of a composite image in a combination unit (5). Because the linear polarization degree of the light incident on a mirror surface (27) of the beam splitter (2) is low, the differences between brightnesses of sub-images picked up by individual image sensors are small. Disturbances are thus counteracted in the composite image.The image pick-up apparatus is preferably used in an X-ray examination apparatus (10) in order to reproduce an X-ray image having a high spatial resolution and few disturbances.

Abstract: An display apparatus has an image displaying device for modulating light by a spatial light modulation element and displaying an image, a relay optical system for forming the image on an imaging plane at a location differing from the image displaying device, an eyepiece optical system for directing the light from the imaging plane to an observer's pupil, and light beam controlling device provided in a portion of the relay optical system for controlling the amount of transmission of a light beam from the image displaying device correspondingly to the inclination of the contrast distribution of the light beam.

Abstract: An optical coupler for use in fiber optics for splitting light signals into two or more portions wherein the intensity of the light on the outgoing optical fibers can be accurately controlled. The optical coupler consists of a sending GRIN lens and two or more adjacent receiving GRIN lenses wherein a portion of each receiving GRIN lens has been removed and the receiving GRIN lenses are attached along a common border formed by the removed portion of the GRIN lenses.

Abstract: The optical coupler includes first, second and third port assemblies and a deflecting element. The first port assembly receives a first optical signal, the first port assembly including a first lensing element. The second port assembly emits a predetermined, transmitted portion of the first optical signal. The second port assembly includes a second lensing element. The deflecting element is positioned between the first and second port assemblies. The third port assembly includes a third lensing element. The deflecting element and the third port assembly are so positioned and arranged such that a deflected portion of the first optical signal is deflected from the deflecting element and directed through the third port assembly. The predetermined, transmitted portion of the first optical signal is directed through the second port assembly without being deflected by the deflecting element.

Abstract: In a dual focusing optical pickup device, a laser beam is incident on an optical member via a beam splitter. Some part of the incident laser beam is reflected by the optical member and then returned to the beam splitter to be focused on an optical disc. The other part of the incident beam is refracted and transmitted through the optical member and then totally reflected by the reflecting member to return to the optical member. The returned beam is focused to the optical disc via the optical member and the beam splitter. The beam which is reflected by the optical member and the beam which is reflected by the reflecting member after being transmitted through the optical member generate a dual focus on the optical disc, in which the dual focus has different focal distances. Therefore, the optical discs of two kinds in which the recording layers are placed at different distances can precisely be recorded or reproduced, respectively.

Abstract: An optical guide (10, 40, 50, 60) for horizontally aligning two vertically stacked images generated by one or two SLMs. The optical guide has a channel separator (10a) that directs both images along two different paths. A pair of aligning reflectors (10b and 10c) on each path vertically shift the images with respect to each other so that at least part of the images on the first path are aligned side-by-side with at least part of the images on the second path. The channel separator (10a) then redirects the images to the image plane 15. Along both paths, at least two of the reflecting surfaces of channel separator (10a) or aligning reflectors (10b and 10c) are optically powered so as to change the width or height of the images.

Abstract: A double Porro prism having an incident surface, an exit surface, and a plurality of reflecting surfaces for internally reflecting light rays from the incident surface to the exit surface. The plurality of reflecting surfaces having a final reflecting surface that is positioned near the exit surface. The double Porro prism also has a ghost preventing surface that is formed between a ridge of the final reflecting surface and a ridge of the exit surface.

Abstract: A variable splitting optical coupler includes a first port assembly, a second port assembly, a movable deflecting element assembly and a third port assembly. The first port assembly includes a first lensing element and receives a first optical signal. The second port assembly includes a second lensing element and emits a variable transmitted portion of the first optical signal. The movable deflecting element assembly includes a movable deflecting element positioned between the first and second port assemblies. The third port assembly includes a third leasing element. The movable deflecting element is so positionable and the third port assembly is so positioned and arranged so that a deflected portion of the first optical signal is deflected from the deflecting element and directed through the third port assembly. The variable transmitted portion of the first optical signal is directed through the second port assembly without being deflected by the deflecting element.

Abstract: Efficient and cost-effective generation of two co-linear laser beams or two or more intersecting beams, for the purpose of alignment as in the construction industry, takes advantage of the unequal divergence of light from a typical laser diode that produces a beam of elliptical cross section. Two roughly equal co-linear beams of light, or two or more intersecting beams, can be generated by reflecting the collimated elliptical beam from preferably two mirror surfaces oriented obliquely to the beam and so as to divide the elliptical beam in two. If one of the reflective surfaces is a beam splitter, three essentially intersecting beams can be generated. In preferred embodiments these three beams are at right angles to each other, particularly for use in construction layout.

Abstract: A screen simulator arrangement includes spaced apart screen and one or more mirror means; said screen means is formed with a plurality of spaced apart transparent portions therein; said mirror means is formed or provided with a plurality of holes or openings therein; said screen and said mirror means are fixedly located relative to each other; the transparent portions of said screen means and the holes or openings of said mirror means are substantially out of register one with the other. An inner screen surface of said screen means and a reflective surface of said mirror means generally face inwardly towards each other, said transparent portions of said screen means and said holes or openings of said mirror means being so out of register one with the other, such that screen portions of said screen means are in substantial alignment/register with holes or openings in said mirror means.

Abstract: A method and apparatus for display of a three dimensional virtual image is provided. The present invention allows one or more objects, real images and virtual images to be displayed at one or more of an arbitrary number of depth levels along a viewer's line of sight. The present invention uses a plurality of beam splitters organized as an optical labyrinth to combine a images with the proper perspective and parallax to result in a three dimensional image.

Abstract: A lens system is provided which has a plurality of lens systems each having a Dove prism and a lens for imaging the light received from its Dove prism on the image field of a CCD camera. Each lens system views a different scene and images that scene on a different portion of the image field. The Dove prisms rotate the scenes so that they can be of maximum size on the image field.

Abstract: A design for a fast absorption optical tomography instrument is disclosed. The subject invention is capable of generating 100 projections of 100 elements each in less than 200 ns. It comprises and optical pulse generator, a tomography ring with temporally multiplexed fiber-optic fan-beam sources and fast detectors, and data acquisition electronics. A single short pulse (<10 ns) of radiation tuned to an absorption transition of the chemical species of interest produces a cross sectional image of concentration. Supplying two such pulses to the instrument can yield simultaneous quantitative images of temperature and absolute concentration in fields with temperature inhomogeneities. Additional pulses lead to concentration images of additional species.

Abstract: An image display apparatus, e.g., a head-mounted display apparatus, which uses a half-mirror or a beam splitter prism and yet has an even more compact structure and provides a favorably flat image surface. A half-mirror (S) is obliquely disposed in front of an observer's eyeball (1), and an image display device (3), e.g., a liquid crystal display device, and a magnifying reflecting mirror (4) are disposed to face each other across the half-mirror (S) and to extend parallel to the observer's line of sight. To widen the field angle without increasing the size and weight of the optical system considerably, at least one surface (L) having positive refractive power is interposed between the eyeball (1) and the half-mirror (S). An even more compact arrangement is obtained by using a beam splitter prism in place of the half-mirror (S).

Abstract: An apparatus and method for increasing resolution and expanding the displayed field of view. The imagery is collimated and split into two paths by a partially reflective mirror set at an oblique angle to the image source. Either path may be blocked by a combination of polarizers and at least one controllable polarization shifting cell(s) (.pi.-cells). This mechanism allows one image source to supply, in alternating sequence, separate imagery to two separate but contiguous portions of a wide angle display. The two collimated image paths are merged about the viewing axis by a one way mirror before being recollimated at the device exit pupil.

Abstract: The modulation by optical valves of three beam coming from a main or auxiliary primary beam of depolarized and collimated white light is achieved by means of two secondary beams of white light that are linearly polarized and perpendicular to each other. The undesirable color components are suppressed to constitute the three constituent color beams of the color image. Through the invention, the geometrical and spectral quality of the image is independent of the main or auxiliary primary beam and the image is as powerful as the one obtained by the standard method of projection. The auxiliary image can be used as a back-up or can be adapted to night-time projection.

Abstract: A light source for flat-panel display comprising reflectors each having a triangular shape in section which are stacked on top of another so as to have at least three slant faces such that at least an uppermost face of the stacked reflectors is perpendicular to a lateral side thereof, a slant face of each of the reflectors being subjected to a surface treatment such that a ray of light incident laterally to the reflectors is reflected substantially parallel to a lateral side thereof, whereby rays of colors which are incident laterally to each of the reflectors advance via the uppermost face of the stacked reflectors substantially perpendicularly.

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: The invention relates to an optical beam divider which subdivides a beam (A), more particularly a laser beam, into at least two beams (B, C) which differ from the original beam (A) only in intensity. To this end the beam divider has a deflecting mirror (2) which is disposed in the path of the beam (A) and which rotates around an axis lying perpendicular to the plane of the mirror and has at least one window (2c) which sweeps the whole cross-section of the beam (A) when the deflecting mirror (2) rotates.

Abstract: A pupil/image reversal prism (FIG. 2) forms a pupil at an image location. Such a prism has specific applicability in a DCR scheme for a thermal imaging system (FIG. 3a, 31 and 32) in which a passive DCR source is implemented by a pupil imager that forms a pupil onto the image of a thermal scene, thereby providing scene-average radiation to a thermal detector array. The pupil/image reversal prism including an input reflective surface (A), an output reflective surface (B) , a positive reflective surface (C) and an intermediate folding reflective surface (D). The reflective surfaces A and B use total internal reflection to provide both transmissive and reflective operation.

Abstract: A broadband area-division beamsplitter that includes a pair of abutting triangular prisms providing two surfaces that are in optical contact in certain areas and are out of optical contact in other areas. One prism surface is substantially planar while adjoining surface of the other prism has alternating protrusions and depressions. The protrusions contact the substantially planar surface to form an optically continuous medium for light transmission. The depressions do not contact the planar surface forming gaps. The two surfaces are oriented on a diagonal so that light incident through one of the other prism faces is incident on the adjoining surfaces at an angle larger than the critical angle, providing total internal reflection at the out-of-contact gap regions. The protrusions and depressions on the one prism surface may be in the form of a corrugation or a checkerboard or some other patterns. The reticulation size of the pattern may be less than about 10 .mu.

Abstract: A beam-combining laser beam source device comprising an airtight housing and a laser beam source unit housed in the housing. The laser beam source unit comprises laser beam sources and collimator optical systems respectively positioned in optical paths of laser beams, which are radiated from the laser beam sources, in order to collimate the laser beams. Optical path adjusting elements are respectively positioned in the optical paths of the laser beams in order to radiate the laser beams along optical paths parallel and close to one another. The laser beam sources, the collimator optical systems, and the optical path adjusting elements are supported on a single support. The housing is provided with a temperature sensor, which detects the temperature in the housing, and temperature adjusting elements which heat or chill the housing on the basis of control of the temperature sensor so that the temperature in the housing is kept constant.

Abstract: A laser interferometry length measurer for determining a moving distance of an object. The measurer includes a 45.degree. rotatory polarization plate for dividing a source light beam to a measuring beam and a reference beam; a reflector, which is placed to the object, for reflecting the measuring beam; a prism for composing the reference beam and the reflected measuring beam into a composed source beam; a beam splitter prism for distributing the composed source beam into a plural light beams which have different phases; and a determination unit to determine the moving distance of the object according to those beams.

Abstract: An optical distributor comprises an optical input (Il), and 2.sup.n optical outputs (01-08) , where n is an integer greater than 1, one or more plane mirror surfaces (8) and transflective means (2, 4, 6). The plane mirror surface or surfaces (8) and the transflective means (2, 4, 6) are arranged to provide one optical path between the input (Il) and each of the outputs (01-08), each path making n transitions only at the transflective means. In a preferred embodiment the transflective means comprise n separate beam splitter stages, the effective lengths of the n separate splitter stages (2, 4, 6) being substantially in the ratio 1.2 2.sup.n. The beam splitters may be formed by transflective coatings on glass substrates.

Abstract: Apparatus for combining information beams by using a space variant mirror in the context of free space optical switching and computing, where light beams comprise beamlets that are focused onto surfaces to form arrays of light spots. Beam combining is achieved by positioning the space variant mirror to coincide with the plane on which the spots are focused, and to thereby allow one beam to pass through the space variant mirror without loss and another beam to be reflected off the space variant mirror, also without loss.

Abstract: A device for the generation of several light beams is used notably to illuminate light spatial modulation screens with the 16/9 format in color image projectors. The aim is to improve the luminous efficiency. The disclosed generator device has a light source producing a primary beam and two wavelength selective mirrors. The two selective mirrors are illuminated by the primary beam and produce two secondary beams of different wavelengths. On the one hand, the two selective mirrors are placed side by side and intercept different parts of the section of the primary beam. On the other hand, a rear face that is at least partially reflective is positioned opposite the source with respect to the selective mirrors.