Abstract: A process and photoactive media for holographic recording and micro/nanofabrication of optical and bio-optical structures via the simultaneous absorption of two-photons by the photoactive media to induce a simultaneous photochemical change in regions of constructive interference within a holographic pattern is disclosed. The photochemical process of polymerization resulting from the simultaneous absorption of two-photons may be used for the microfabrication of micro and nanoscaled features, holographic data storage, and the formation of switchable diffraction gratings.

Abstract: Disclosed are apodizers and methods for redistributing the intensity of a light beam. Particularly, single component apodizers are disclosed. The single component apodizers include a single lens component that is capable of redistributing the intensity of a coherent light beam.

Abstract: The present invention relates generally to an optical element (OE) which can serve as an optical analogue to digital converter (OADC) and/or an optical digital to analogue converter (ODAC), and uses therefor. The OE can be usefully employed in a variety of applications to transform analogue information present in a light wave front into digital light signals and/or to transform digital information into analogue information in the form of the physical parameters of a light wave front.

Abstract: A multi-faceted concentrator apparatus for providing ultra-accelerated natural sunlight exposure testing for sample materials under controlled weathering conditions comprising: facets that receive incident natural sunlight, transmits VIS/NIR and reflects UV/VIS to deliver a uniform flux of UV/VIS onto a sample exposure plane located near a center of a facet array in chamber means that provide concurrent levels of temperature and/or relative humidity at high levels of up to 100× of natural sunlight that allow sample materials to be subjected to accelerated irradiance exposure factors for a significant period of time of about 3 to 10 days to provide a corresponding time of about at least a years worth representative weathering of sample materials.

Abstract: An image display device including a polarization selective holographic optical device for diffracting illuminating light, and a reflection type spatial optical modulator for modulating the state of polarization of the illuminating light diffracted by the polarization selective holographic optical device is disclosed. The device includes a plurality of each of two areas of respectively different incidence polarization orientation dependencies of the refractive index, with the layers being layered sequentially alternately. An image display apparatus including the above image display device, a light source, an illuminating optical system and a projection optical system is also disclosed. With the present optical display device and optical display apparatus, the utilization efficiency of the illuminating light may be improved, while the device and the apparatus may be reduced in size and production cost, as uniformity and high contrast of the image displayed are achieved simultaneously.

Abstract: The distance between a spatial light modulating device 7 and a lens 8 is set such that a real or virtual image position 9, 9′ (L, L′) of object light formed by the lens 8 is an observing position of a hologram 12′. Since a reconstructed image is fixed at the observing position L, L′, noise existing in the reconstructed image of the spatial light modulating device 7′ if any is fixed at the observing position and thus is unremarkable as noise, whereby the noise is substantially lowered.

Abstract: In the multilayer volume hologram 1 of the invention, the adhesive layer 5, volume hologram 6 and surface protective film 7 are laminated on the application member 2 in this order, and the breaking strength of the hologram layer should be larger than the peel strength between the surface protective film and the volume hologram layer and smaller than the peel strength with which the hologram layer is peeled off the application member and the breaking strength of the surface protective film. This multilayer volume hologram provides a more improved protection for the volume hologram. A portrait replacement or falsification of an information area ensures that the volume hologram layer can break down. Thus, more reliable counterfeit-proofness is achievable.

Abstract: A cutting-free method for making a hologram sticker includes the steps of adding a releasing layer on a base; plating a metal layer on the releasing layer; printing an epoxy layer with a holographic pattern on the metal layer; chemically etching the metal layer not covered by the epoxy layer together to remove the excess metal layer; washing the residual layers; drying the washed and etched layers; applying an adhesive layer on top of the washed epoxy layer and applying a releasing layer on top of the adhesive layer.

Abstract: An optical element that receives a first incident light and a second incident light through a main surface and allowing the first and second incident lights to be transmitted therethrough, the first and second incident lights being linearly polarized lights having substantially orthogonal polarizing directions and having different wavelengths &lgr;1 and &lgr;2 respectively, the optical element receiving a first reflected light and a second reflected light generated when the first and second incident lights are reflected from a reflector through the other face, and allowing the first and second reflected lights to be transmitted therethrough again, the optical element has a polarizing hologram that allows the first incident light, the second incident light, and the second reflected light to be transmitted therethrough upon receiving these lights and that diffracts the first reflected light upon receiving this light; and at least one wavelength plate that varies at least one of polarizing states of all of the f

Abstract: A system for producing a white-light interference hologram includes a camera adapted for recording a first and a second bitmap image of a scene from separate vantage points, and the separation distance of the vantage points, a computing engine adapted to compute three-dimensional x, y, and z characteristics of an interference hologram topology for the scene from the bitmap image and separation data, wherein x and y are two dimensional locations of bits in a bitmap of the topology and z is a depth dimension for each x,y bit, and a printer adapted to print in color the x,y bitmap, and to create the depth dimension z at each x,y bit location, providing thereby a three-dimensional interference hologram topology for the scene. In a preferred embodiment the depth dimension is created by electrophoresis, using a medium having an electrophoretic gel layer, with the ink applied to the gel in a bit-mapped pattern being ionic in nature, and capable of being migrated in the gel layer by electrophoresis.

Abstract: A system for forming holographic pixels on the surface of a workpiece is disclosed. The system comprises a laser generating a laser beam; a beam splitter dividing the laser beam into a first beam and a second beam; a controller providing as output at least one control signal; and at least one beam deflector receptive of the first and second laser beams guiding the first and second laser beams along different paths to a prescribed pixel location on the surface of the workpiece, thereby combining the first and second laser beams at a prescribed azimuthal direction and included angle. At least one beam deflector is receptive of the at least one control signal thereby controllably deflecting at least one of the first laser beam and the second laser beam to the prescribed pixel location.

Abstract: An apparatus and method for hologram induced deposition of material for use in the formation of three-dimensional structures is described. An electromagnetic energy source may be directed in the form of a hologram to a process chamber with a medium. The medium may be an organometallic gaseous medium. The hologram may induce the medium to form a solid structure associated with the shape of the hologram. The pressure of the gaseous medium may range from subatmospheric to greater than 100 psi. Alternatively, the medium may be a liquid polymer, a solid particle, or others. The hologram may be formed with an LCD panel or other means. Further, a holographic movie may be projected into one or more mediums to form complex three-dimensional structures.

Abstract: This invention relates to the photo-sensitive thermoplastic top-layer of optical media for registration of holograms, where the media consists of three transparent layers where the bottom layer is a glass substrate, the mid layer is an electro-conductive film of tin dioxide, and the top layer is a thermoplastic photo-sensitive amorphous molecular semiconductor film made of a matrix which has donor properties and forms transport bands for holes, and were the matrix is doped with; a photo-sensitive substance (CICT) that has intramolecular physically separated parts with donor and acceptor properties, respectively, and which creates an intramolecular electron-hole pair when absorbing a light quantum, and which has a HOMO-level which is below the HOMO-level of the matrix substance, and a substance with acceptor properties that forms transport bands for electrons, which has a similar ring structure as the acceptor part of CICT to ensure a barrierless transfer of excited electrons from CICT to acceptor-molecules

Abstract: A holographic shrink wrap element containing a shrink wrap film and a layer on the shrink wrap film, wherein the layer contains a holographic image. A process for preparing a holographic shrink wrap element includes providing, in the following order, a holographic polymer film having a holographic surface, a layer on the holographic surface and a shrink wrap film, and removing the holographic polymer film, leaving the holographic image on the layer.

Abstract: Optical systems for selectively altering the propagation of light are provided. A representative optical system incorporates an optical device that includes a first para-electric holographic medium. The first para-electric holographic medium stores a first hologram that can exhibit a first active mode. The first hologram exhibits the first active mode when a first electric field is applied to the first para-electric holographic medium. When in the first active mode, the first hologram directs light incident upon the first holographic medium to a first location. Methods and other systems also are provided.

Abstract: Disclosed is a curved surface element (e.g., light bulb, ornament, light pipe, etc.) which has at least a portion thereof (inner or outer surface) covered with a holographic diffraction grating which was constructed to be essentially distortion free on said curved surface, whereby such diffraction grating diffracts light to emit color to the observer. The diffraction grating can take for form of a holographic optical element (HOE) attached to the curved surface or a diffractive holographic optical pattern (HOP) embossed into the curved surface.

Abstract: A method for storing data in a holographic storage medium comprises the steps of dividing a bit stream of binary data into data groups, encoding the data groups as binary patterns, and storing the binary patterns holographically as data pages. Each binary pattern comprises channel bits, wherein the number of “off” channel bits is greater than the number of “on” channel bits. To retrieve information from the storage medium, the medium is illuminated and resultant light signals are gathered. The light signals are converted to the binary patterns, and the binary patterns are converted to the data groups. Binary patterns stored in the storage medium only slightly perturb subsequent reading and writing of data, since the patterns have fewer “on” channel bits than “off” channel bits.

Abstract: Holographic patterns are produced by utilizing a laser to illuminate a workpiece with an interference pattern, with sufficient laser power to ablate the workpiece where it is illuminated by the laser, and moving the workpiece and the interference pattern relative to each other.

Abstract: The present invention makes it possible to reduce the size of an optical system for multiplex recording or reproduction of information utilizing holography.

Abstract: A method and system for generating a hologram include a computer (104) connected to a printer (108). A mathematical description (102) of an object, including for example the physical dimensions of the object, is provided to the computer (104). The computer (104) computes a holographic interference pattern based on the mathematical description (102) of the object, and than transmits the computed holographic interference pattern data (106) to the printer (108). The printer (108) prints or otherwise fixes the holographic interference pattern to a print medium (107) to produce a holograph (110). A holographic (three-dimensional) image (114) of the object can then be produced by directing a light beam (118) from a light source (112) onto a surface of the hologram (110), so that the light will interfere with the pattern to generate the holographic image (114).

Abstract: A partially collimated light beam (2) is sent through a substrate matrix of a plurality of nested individual joined geometrically shaped cells (301) wherein each of the cells is further comprised of subcells (502) contains containing a patterned volume holographic diffuser (302) which produces a transmitted diffused light beam (305) from each of the cells and then superimposes each transmitted diffused light beam from each of the cells to produce a combined resultant diffused light beam. The combined resultant diffused light beam has an angular luminance distribution profile curve (83) with sharply vertical profile slopes (81) at halfpeak points (20) and a substantially flat and wide peak (84), this resultant diffused light beam advantageously produces a uniform resultant luminance over a wide range of view angles with a predetermined beam spread and beam deflection angle at said predetermined viewer head box location (100).

Abstract: An optically variable security device comprising a thin film reflection filter structure (23) which exhibits a first optically variable effect; and a relief structure (20) on or in the thin film reflection filter structure which exhibits a second optically variable effect.

Abstract: A single method and apparatus for producing many of the most common types of hologram from digital data is disclosed. The data are generated entirely by a computer as a 3-D (animated) model or from multiple 2-D camera images taken of a real 3-D (moving) object or scene from a plurality of different camera positions. The data are digitally processed and displayed on a small high resolution spatial light modulator (SLM). A compact low energy pulsed laser, is used to record composite holograms. The present invention permits the creation of restricted or full parallax master transmission or reflection type composite holograms, known as H1 holograms, that can be copied using traditional methods. Alternatively the same invention and apparatus permits the direct writing of hologram without the need to pass through the intermediate stage of the H1 transmission hologram.

Abstract: The invention presents the concept of self-referenced holographic data recording. In exemplary embodiments, the invention comprises methods of recording holograms on holographic data storage media; media produced by such methods; and self-referencing holographic data storage systems. A method of recording data in a holographic recording medium may comprise illuminating a medium with a data encoded first optical beam, optically directing a zero frequency Fourier component of the first optical beam to create a second optical beam, and illuminating the medium with the second optical. In some embodiments, for example, a self-referencing holographic data storage system has a single optical path directed towards a medium.

Abstract: Disclosed are articles having a color shifting film and indicia located behind the color shifting film. The indicia include at least a first and second colored portion, the first portion including a first fluorescent colorant. The second colored portion is non-fluorescent but has a color similar to that of the first portion to enhance concealment of the indicia under certain viewing conditions. At least one of the colored portions is patterned.

Abstract: A resonator system is disclosed for use in illuminating a diffractive element. The system includes a source of an electromagnetic field having a wavelength of &lgr;, and first and second optical elements, each of which is at least partially reflecting.

Abstract: A method for monitoring diffraction while recording a hologram includes: generating a source beam; generating a data beam by projecting a first component of the source beam through a data source, the data beam having a first polarization; generating a reference beam by adjusting a polarization of a second component of the source beam to provide a second polarization; recording a hologram in a holographic medium from an interference between the data beam and the reference beam; and measuring an offset component in an output arm of the data beam.

Abstract: A hologram recording film has a hologram image of an object recorded in a volume hologram photosensitive material by holographic duplication and further has a hologram image of an additional information pattern, e.g. a character or an image, recorded superimposedly in the same volume hologram photosensitive material simultaneously with the holographic duplication so that the additional information pattern is reconstructable in a plane with a depth from the hologram plane. Reflection type additional information is recorded in the hologram recording film so as to be reconstructable simultaneously in superimposition with a reconstructed image from the volume hologram. In addition, transmission type additional information that is in mirror image relation to the reflection type additional information is recorded in the hologram recording film so as to be reconstructable simultaneously in superimposition with the reconstructed image from the volume hologram.

Abstract: A holographic storage apparatus for recording data in a holographic medium includes at least one light source for generating a reference beam and a signal beam. The reference beam is preferably a phase beam of unchanging phase content. The apparatus also includes a holographic medium placed in a path of the reference beam and a path of the signal beam. The holographic medium has a first face and both the reference beam and the signal beam enter the holographic medium through the first face. The holographic medium also includes a data reflective surface. The reference beam and the signal beam interfere in the holographic medium to create a hologram only after at least one of the reference beam and the signal beam have reflected off of the data reflective surface.

Abstract: This invention relates to a solar control film that blocks the sunlight, when applied to various windows of automobiles, buildings or exhibition places and that prevent any second accident caused by broken glasses at an accident. From the solar control film, a surface protective layer, a plastic film substrate, a hologram-engraved layer, a metal deposition layer, a pressure sensitive adhesive layer and a release film are laminated in due order. The solar control film of this. Hence the above-described solar film has a basic function such as an excellent blocking rate of visible and infrared rays, while demonstrating an additional antifog action and an elegant look due to the hologram effect.

Abstract: A diffusive optical element exploiting holography is designed in such a way that, the higher the intensity of incident light in a wavelength range, the lower the rate at which the intensity of diffused light in that wavelength range is reduced with increasing angle relative to the maximum intensity direction. Thus, the lower the intensity of incident light in a wavelength range, the narrower the range of angles at which light is diffused in that wavelength range. This makes it possible to use light diffused at angles within a predetermined range relative to the maximum intensity direction, and thereby enhance light use efficiency in a wavelength range in which light intensity is comparatively low. This diffusive optical element is employed in an illumination optical system, which is used to illuminate photographic film from which to read images.

Abstract: An illumination panel for illuminating an object, comprising a substrate, a light diffractive grating and a light source. The substrate is made from an optically transparent material having first and second area surfaces disposed substantially parallel to each other and a light input surface for conducting a light beam into the substrate. The light diffractive grating is mounted to the first areal surface and has a slanted fringe structure embodied therein for diffracting the light beam falling incident thereto, along a first diffractive order of the slanted fringe structure. The light source produces a light beam for transmission through the input surface and direct passage through the substrate to the slanted fringe structure so as to produce an output light beam of areal extent that emerges from either the first or second areal surface along the first diffractive order, for use in illuminating an object.

Abstract: Systems and methods for adjusting the polarization of one or more recording laser beams can correct (in whole or in part) for the changes in the polarization of the recording laser beam(s) caused by changes in the dominant polarization direction within the film substrates used for recording holograms. Using information about the dominant polarization direction of portions of holographic film substrate, a polarization adjusting device can be used to adjust the polarization of the recording laser beam(s) to compensate for the effects that changes in the dominant polarization direction of the holographic film substrate have on the recording laser beam(s) and thus the recorded hologram.

Abstract: Disclosed are articles having a color shifting film and indicia located behind the color shifting film. At least a first and second colored portion are arranged as a foreground and background of the indicia. The first portion includes a first fluorescent colorant and the second portion includes a different second fluorescent colorant. At least one of the colored portions is patterned. Bright fluorescent emission is visible from the different colorants over different angular ranges to produce high contrast reversal or change.

Abstract: A composite sheet having the capability of having embossed therein a holographic image or diffraction grating image having a structure of multiple layers including a plastic film carrier, lacquer, metal and wax or siloxane. It may be adhered to a substrate by heating, pressing or stamping without the necessity of removing the plastic film carrier and may have a holographic image embossed therein during the step of heat pressing or stamping or in a separate operation at a different time.

Abstract: A hologram laminate allows traces of separation of the hologram to be clearly left on both the adherend and the hologram label and hence makes it possible to prevent reuse of the hologram and is excellent in graphical design function and suitable for certification purposes. A hologram label used for the fabrication of the hologram laminate is also provided. The hologram laminate has a metal thin-film layer, a release pattern, a transparent film, a hologram layer and a surface protective layer laminated on an adherend in the order mentioned. The hologram laminate is separable between the adherend and the transparent film. When the hologram is separated, the metal thin-film layer is left on the adherend in a pattern corresponding to the release pattern. The hologram label has a release sheet in place of the adherend in the hologram laminate.

Abstract: A hologram laminate allows traces of separation of the hologram to be clearly left on both the adherend and the hologram label and hence makes it possible to prevent reuse of the hologram and is excellent in graphical design function and suitable for certification purposes. A hologram label used for the fabrication of the hologram laminate is also provided. The hologram laminate has a colored layer, a release pattern, a transparent film, a hologram layer and a surface protective layer laminated on an adherend in the order mentioned. The hologram layer includes a volume hologram layer and a relief hologram layer having a transparent thin-film layer over the surface of a relief interference fringe pattern. The volume hologram layer and the relief hologram layer are superimposed so as to be switchable from one to another. The hologram laminate is separable between the adherend and the transparent film.

Abstract: An image reproducing apparatus having a small size and which is highly portable reproduces an image contained within a hologram or holographic stereogram. In one embodiment, when a movable section movably attached to an apparatus body is moved from a first position, in which the movable section abuts the apparatus body, to a second position in which the movable section and apparatus body are separated, illumination light from a light source is irradiated at a predetermined incidence angle onto a hologram or holographic stereogram attached to a hologram attach section. In other embodiments, light from a light source is reflected from an edge portion of a light transmitting member, or from a separately provided mirror, to be irradiated at a predetermined angle onto the hologram or holographic stereogram.

Abstract: A lightweight contact holographic sight includes a housing and a base which form a compartment containing a laser diode, an associated power source, and optical elements including a mirror, an off axis collimator, a reflection grating, and an image hologram of a reticle pattern, wherein the optical elements are arranged within the compartment to direct and fold the laser beam in a substantially generally vertical path. In one aspect of the invention, an elevation and windage adjustment mechanism is provided to rotate the reflection grating about two orthogonal axes to thereby adjust the projected reticle pattern for windage and elevation. In another aspect of the invention a removable battery compartment including a cam surface which is releasably contacted by a cam lever arm pivotally mounted on the sight housing or the base to allow for quick tool-less removal of the compartment for battery replacement.

Abstract: The present invention relates to a method and apparatus for display of three-dimensional images and production of mega-channel phase-encoded optical communications. In certain embodiments, the device of the present invention allows for the creation and display of real-time, three-dimensional moving holograms. In the present invention, a computed image or virtual model of a real object is stored in a computer or dedicated digital signal processor (DSP). The stored image or model is then converted by the computer or DSP into its Fourier, or holographic, transform. The holographic transform is displayed on a light modulation device that is illuminated by a one portion of a laser emission. The remaining portion of the same laser emission is combined with the holographic transform at a plane to create a three-dimensional image.

Abstract: A linear axis spectral analysis system is enclosed. The spectral analysis system utilizes a prism-volume holographic transmission grating-prism combination to achieve a linear axis between input and detector. This design, when held with low thermal expansion materials, is extremely insensitive to temperature and vibration, allowing for enhanced accuracy without the need of temperature control. Further, the spectral analysis system provides the ability for extreme compactness.

Abstract: A projection television is provided comprising at least three image projectors for projecting respective images of different colors onto a holographic projection screen. One of the projectors has a first, shortest optical path disposed in a substantially orthogonal orientation with the holographic projection screen and at least two of the projectors are disposed in adjacent, stepped-relation to one another and have respective optical paths that are (i) selectively defined by the stepped-relation of the projectors; and (ii) converge toward the first optical path in a non-orthogonal orientation so as to define angles of incidence corresponding to a lowest level chromatic aberration of the images by the holographic projection screen. The projection screen is formed by a three dimensional hologram representing a three dimensional array of lenticular elements disposed on a substrate.

Abstract: A cutting-free method for making a hologram sticker includes the steps of adding a releasing layer on a base; plating a metal layer on the releasing layer; printing an epoxy layer with a holographic pattern on the metal layer; chemically etching the metal layer not covered by the epoxy layer together to remove the excess metal layer; washing the residual layers; drying the washed and etched layers; applying an adhesive layer on top of the washed epoxy layer and applying a releasing layer on top of the adhesive layer.

Abstract: Holographic printers for producing simultaneous and near real time white light viewable holographic imagery are disclosed. Such printers include fiber optics for dividing the reference beam into a plurality of identical reference beams each intersecting the object beam path at the recording medium. In one embodiment, the recording medium is simultaneously exposed to both the object beam and the plurality of reference beams. An alternate embodiment is provided for sequentially opening each of the reference beam shutters with the opening of the object beam shutter. Preferably, the printer includes a liquid crystal panel and a computer for supplying images in the liquid crystal panel between each sequential opening of the shutters. For the formation of integral holograms, fiber optics are provided for dividing the object beam.

Abstract: An apparatus for forming at or closer than infinity one or more images of multiple sources is disclosed. The new concept of this invention will permit the manufacture of a flat holographic beamsplitter and a flat holographic analog of a spherical mirror-beamsplitter. The combination of these elements will produce a very compact full color in-line infinity display system of a thickness ranging from ⅜ of an inch thickness to ⅝ inch (based on size) which requires only an image input screen to provide a collimated display. This ultra-thin collimating display can be used to simulate the real aircraft, marine or automobile windows etc., when cut to replace the real windows thereby providing the observer with a true infinity display through actual window size and thickness. Furthermore these windows can be joined-horizontally and vertically, as the application requires.

Abstract: In order to prevent decrease in diffraction efficiency that is brought about when the diffraction peak wavelength shifts due to, for example, the shrinkage of a volume-hologram-recording photosensitive material layer 1, the present invention provides an original volume hologram film 10. The original volume hologram film 10 has a volume-hologram-recording photosensitive material layer 1 provided on a film 2, and an adhesive layer 8 provided on a film 9. The films 2 and 9 are affixed to each other with the layer 1 and 8 facing each other. The volume hologram has been recorded in the layer 1. The layer 8 can migrate an ingredient to the layer 1 to shift the diffraction peak wavelength to the opposite side.

Abstract: The object of the present invention is to provide a holographic notch filter which can favorably reject and remove a narrow, desired range of wavelengths of the incident light and a method of easily manufacturing the holographic notch filter. For achievement of the above object of the present invention, a multi-structure holographic notch filter 2 having a holographic recording material 4 arranged on which modulations of the refractive index are recorded by two-beam interference is provided as characterized in that a thin-film filter element 6 is fabricated from a thin form of the holographic recording material 4 in which modulations of the refractive index are recorded by the two-beam interference and a plurality of the thin-film filter elements 6 are joined together to develop a layer arrangement.

Abstract: A two-color holographic recording apparatus reduces error signals possibly included in reproduced digital data signals. The two-color holographic recording apparatus has first, second and third light shutters for passing or blocking gate light, signal light and reference light incident on a recording medium respectively, and a controller for controlling the respective states of the first, second and third light shutters.

Abstract: A holographic optical data storage device according to the present invention includes a photopolymer layer having an upper surface and an oppositely disposed lower surface. The device includes a substantially transparent upper substrate layer having a first inside surface lying adjacent to the upper surface of the photopolymer layer. The device includes a substantially transparent lower substrate layer having a second inside surface lying adjacent to the lower surface of the photopolymer layer. The upper and lower substrates have first and second peripheral edges respectively with an opening formed therebetween. The device further includes a connection member engaged to the upper and lower substrates wherein the connection member seals the opening. A method of fabricating a holographic optical data storage device is also provided.

Abstract: A projection screen (30) for representation of images by back-projection comprises a plurality of holographic-optical elements (10) arranged in one plane. The holographic-optical elements are illuminated by a projector (14) comprising three projection devices (22,24,26). Each projection device (22,24,26) generates a light bundle (16,18,20) respectively including the chromatic components of an image to be projected. Each holographic-optical element (10) comprises at least one lens and one diffraction grating which are diffracted in such a manner by the different light bundles (16,18,20) that the holographic-optical element (10) will emit an exiting light bundle (28) with an identical exit angle (&bgr;) in the direction of the viewer (12). Such a projection screen will scatter the light only to a small extent so that the projection screen can be used also at daylight and for large-surface image projection.