Abstract: Pre-sensitization techniques can be used in conjunction with holographic recording materials to allow high quality holographic stereograms to be recorded in those holographic recording materials using pulsed lasers. Additional hologram production system hardware and software designs for use with pulsed lasers are disclosed.

Abstract: The present invention relates to a three-dimensional (3D) hologram display system. The 3D hologram display system includes a projector device for projecting an image upon a display medium to form a 3D hologram. The 3D hologram is formed such that a viewer can view the holographic image from multiple angles up to 360 degrees. Multiple display media are described, namely a spinning diffusive screen, a circular diffuser screen, and an aerogel. The spinning diffusive screen utilizes spatial light modulators to control the image such that the 3D image is displayed on the rotating screen in a time-multiplexing manner. The circular diffuser screen includes multiple, simultaneously-operated projectors to project the image onto the circular diffuser screen from a plurality of locations, thereby forming the 3D image. The aerogel can use the projection device described as applicable to either the spinning diffusive screen or the circular diffuser screen.

Abstract: The three-dimensional system discloses screens (12, 16) that produce magnified three-dimensional images (6) that can be projected before large audiences who can view said images without special glasses or viewing aids. The screens disclosed therein are active optical systems which, together with the projection optics, serve to reconstruct and present to the audience the same light waves as though the three-dimensional scene actually exists. The present invention discloses improved screens for this system as well as methods of manufacturing said improved screens.

Abstract: An array of discrete sensors disposed on a substrate, each sensor comprising a holographic support medium and a hologram disposed throughout the volume of the medium, whereby interaction with an analyte results in a variation of a property of the medium.

Abstract: A video holographic display device operates so that the size of a reconstructed three dimensional scene is a function of the size of the hologram-bearing medium; the reconstructed three dimensional scene can then be anywhere within a volume defined by the hologram-bearing medium and a virtual observer window through which the reconstructed three dimensional scene must be viewed. This contrasts with conventional holograms, in which the size of the reconstructed scene is localised to a far smaller volume and is not a function of the size of the hologram-bearing medium at all.

Abstract: The present invention concerns methods and devices for creating and printing variable size and variable resolution holographic stereograms and holographic optical elements using computer rendered images of three-dimensional computer models or using computer processed images. The present invention is an apparatus and method for printing one-step, full-color, full-parallax holographic stereograms utilizing a reference beam-steering system that allows a reference beam to expose a holographic recording material from different angles. More particularly, a coherent beam is split into object and reference beams. The object beam passes through an object beam unit in which a rendered image is displayed, while the reference beam passes through the reference beam-steering system. The object and reference beams interfere with each other at an elemental hologram on a holographic recording material.

Abstract: A dynamic three-dimensional image can be modified in response to poses or gestures, such as hand gestures, from a user. In one implementation, the gestures are made by a user who selects objects in the three-dimensional image. The gestures can include indications such as pointing at a displayed object, for example, or placing a hand into the volume of space occupied by the three-dimensional image to grab one or more of the displayed objects. In response to the gestures, the three-dimensional display is partially or completely redrawn, for example by an alteration or repositioning of the selected objects. In one implementation, a system simulates the dragging of a displayed three-dimensional object by a user who grabs and moves that object.

Abstract: A method and a device for encoding and reconstructing computer-generated video holograms using a conventional LC display: it provides holographic reconstruction of three-dimensional scenes using electronically controllable pixel in a holographic array (3) with a conventional resolution, and is reasonably free from flickering and cross-talk. Reconstruction is in real time, and for both eyes at the same time, over a large viewing zone. The method takes advantage of an optical focusing means (2) in order to image vertically coherent light emitted by a line light source (1) into viewing windows (8R, 8L) after modulation by the pixel array (3). The holographic reconstruction (11) of the scene is rendered visible from viewing windows (8R, 8L) for both eyes of an observer by way of diffraction at the pixels.

Abstract: Hologram recording medium is manufactured by using computer. On a recording plane 20, cell position points Q are defined at a pitch Ph along the cell position lines f(i) which are arranged on the recording plane 20 at a pitch Pv. For each individual cell position point Q, an amplitude A and a phase ? of a synthetic wave of object light components emitted from a plurality of sample points on an associated image contour are determined by computation. At each individual cell position point Q, is positioned a three-dimensional cell C, having a diffraction grating G, with a phase that is in accordance with the phase ?, formed in an effective region E having an area that is in accordance with the amplitude A. The diffraction grating G is formed by periodically positioning staircase steps with a period ?. With the three-dimensional cell C, a length Cv is set to 20 ?m, a width Ch is set to 0.4 ?m, and the period ? is set to approximately 1 ?m.

Abstract: A method and a device for encoding and reconstructing computer-generated video holograms using a conventional LC display: it provides holographic reconstruction of three-dimensional scenes using electronically controllable pixel in a holographic array (3) with a conventional resolution, and is reasonably free from flickering and cross-talk. Reconstruction is in real time, and for both eyes at the same time, over a large viewing zone. The method takes advantage of an optical focusing means (2) in order to image vertically coherent light emitted by a line light source (1) into viewing windows (8R, 8L) after modulation by the pixel array (3). The holographic reconstruction (11) of the scene is rendered visible from viewing windows (8R, 8L) for both eyes of an observer by way of diffraction at the pixels.

Abstract: The invention provides an optical multiplexing device comprising: a plurality of optical sources with integrated collimators (31-37) whose output beams are combined by mirrors (41-47) or other beam deflecting elements, which combine the beams into a single composite beam diverging from a common origin point (30). This is done by arranging the mirrors (41-47) staggered at different distances from the origin point, and at different angles to each other taking accourt of the dependence of the beam divergence in far field on the distance from the origin point.

Abstract: The present invention relates to a method of displaying an object, in which the object is formed by displaying a two-dimensional object image on a plurality of displaying surfaces which are respectively disposed at different positions having different depths from each other. The luminance of the two-dimensional image displayed on each displaying surface is changed independently such that when the object image is moved farther in depth, the luminance of the object image displayed on a surface nearer to the observer is reduced and the luminance of the object image displayed on a surface farther from the observer is increased.

Abstract: A video holographic display device operates so that the size of a reconstructed three dimensional scene is a function of the size of the hologram-bearing medium; the reconstructed three dimensional scene can then be anywhere within a volume defined by the hologram-bearing medium and a virtual observer window through which the reconstructed three dimensional scene must be viewed. This contrasts with conventional holograms, in which the size of the reconstructed scene is localised to a far smaller volume and is not a function of the size of the hologram-bearing medium at all.

Abstract: A method of displaying a computer generated hologram includes displaying the image as a set of facets that approximated to the true shape of the object to be displayed. Each of these facets is populated with points that together make up the image. The invention provides a number of array structures that allow adjoining facets at different orientations and angles to be populated with point without creating areas around the join of either point overpopulation or point underpopulation, and so results in a higher quality image. The invention is mainly applicable for producing interference base Computer Generated Holograms, but can also be used in other types of 3D display that make up objects from an array of points.

Abstract: Hologram production devices can include holographic recording material deposition systems to deposit holographic recording material as needed by the hologram production device. Various nozzles, ink jets, and similar devices can be used to deposit one or more components of the holographic recording material on to an appropriate substrate. If needed, the material is pre-processed to, for example, provide material stability for the holographic recording material. Once holograms are recorded in the holographic recording material, the material can be post-processed as desired.

Abstract: A method of generating a Computer Generated Hologram (CGH) using the diffraction specific algorithm allows a curved wavefront to be produced from a single hogel, rather than the planar waves of the prior art. This allows a wavefront from a singel hogel to generate a point in the image volume. An imaginary wavefront is transmitted from each point in the image volume and sampled at a plurality of points over the hogel. These samples are used to produce a set of complex Fourier coefficients that can be used to approximate the original waveform.

Abstract: Certain types of holographic recording materials can be used to updateably record holographic stereograms formed when fringe patterns are generated through interference of an object laser beam containing image information with a reference laser beam. In this manner, calculation of fringe patterns is avoided, and instead perspective information is computed for a scene or object to be displayed, the information is downloaded to display hardware such as a spatial light modulator, and fringe patterns are subsequently generated through interference of an object laser beam containing this information with a reference laser beam in the classic hologram recording scheme. Previously recorded holographic stereograms or component hogels are updated by erasing the stereograms or component hogels and recording updated stereograms or component hogels, or by recording updated stereograms or component hogels in a separate portion of the holographic recording material.

Abstract: Hologram production techniques can combine source data representing realistic information describing an environment with source data providing representational information describing a feature of the environment and/or some object interacting with the environment. The combined data is used to produce holograms, and particularly holographic stereograms including features that enhance the visualization of the environment depicted in hologram. A haptic interface can be used in conjunction with such holograms to further aid use of the hologram, and to provide an interface to secondary information provided by a computer and related to the images depicted in the hologram.

Abstract: An apparatus and method for displaying viewer reactions to a display object. The display object is divided into a plurality of spatial regions, viewer reactions are collected to an exposure to the display object and correlated with the spatial regions, and the display object is displayed with an aspect of the display of each spatial region being a function of the viewer reactions for the region.

Abstract: An autostereoscopic viewer is employed to produce aberration corrected images to simulate a virtual presence by employing pairs of projector optical components coupled with an image corrector plate and a field lens. Images are designed with magnifications and optical qualities and positioned at predetermined eyezones having controlled directional properties. The viewer's eyes are positioned in these eyezones. The size of these zones is related to the aperture of the projection lenses, the magnification produced by the Fresnel(s), and the optical properties and position of the image corrector plate.

Abstract: There is disclosed a method and apparatus for the presentation of three-dimensional images, where light beams with appropriate intensity and optionally with appropriate color are projected in different viewing directions and thereby creating a three-dimensional image. The light beams are created with a light emitting surface (10) comprising cyclically addressable light sources (S). The surface (10) is positioned behind a screen (20) comprising pixels (P) with a controllable light transmission or reflection. The light beams emitted from different light sources (S) illuminate the individual pixels (P) from different directions. According to the invention, the distance between the light sources (S) is larger than the distance between the pixels (P), and the light sources (S) are positioned so much away from the pixels so that the number of pixels (P) illuminated by one light source (S) is greater than the number of light sources illuminating one pixel (P).

Abstract: A computer-generated hologram comprising a plurality of cells. The hologram has information recorded therein, the information operable to recreate a stereoscopic image of an object. At least one of said plurality of cells Pj has information related to a luminance TWLci (?XY, ?YZ) of a virtual point light source Qi from a plurality of virtual point light sources. The luminance corresponds to a point S on the object. The point S is on a straight line between said one of the plurality of cells Pi and the virtual point light source Qi.

Abstract: A light direction switching apparatus and method is described. The light direction switching apparatus comprises a passive birefringent lens (138), e.g. a birefringent lenticular screen, and a switchable polariser (146). By switching the polariser (146), different directional distributions of output light are provided. The light direction switching apparatus may be used with or incorporated in a display device, such as a liquid crystal display device, to provide a display device switchable between a two dimensional mode and an autostereoscopic three dimensional mode, or to provide a multi-user display device where different images are displayed to different viewers. The light direction switching apparatus may also be used to provide switchable brightness enhancement of reflective or transflective display devices. The light direction switching apparatus may also be used to provide a fiber-optic switching apparatus. The switchable polariser may be mechanically switchable or electrically switchable.

Abstract: An improvement to the above described techniques for producing a holographic stereogram. The present invention uses a hologram lens in the process of creating the holographic stereogram, and also uses Fourier transforms of the images for projection onto the recording medium, not the images themselves. A lens between the generated images and the recording medium performs the inverse Fourier transform to convert the image back into a normal image.

Abstract: Between a spatial beam modulator for modulating an object beam and a one-dimensional diffuser plate for diffusing the object beam modulated by the spatial beam modulator in a one-dimensional direction, there is arranged an object projection optical system for processing the object beam modulated by the spatial beam modulator in such a manner that, in the one-dimensional direction of the one-dimensional diffuser plate, images displayed by the spatial beam modulator are formed on the one-dimensional diffuser plate, and, in a direction substantially orthogonal to the one-dimensional direction, the object beam is condensed onto a hologram recording medium. In the one-dimensional direction of the one-dimensional diffuser plate, the images displayed by the spatial beam modulator are formed on the one-dimensional diffuser plate, whereby blurring of the images with the one-dimensional direction as a non-parallactic direction can be suppressed.

Abstract: Pre-sensitization techniques can be used in conjunction with holographic recording materials to allow high quality holographic stereograms to be recorded in those holographic recording materials using pulsed lasers. Additional hologram production system hardware and software designs for use with pulsed lasers are disclosed.

Abstract: A method of computing a computer generated hologram (CGH) for use in displaying a holographic image of a replay object. The method of generating a first computer generated hologram corresponding to the desired replay object (step 1); subdividing the first computer generated hologram into a plurality of blocks, each representing a sub CGH (step 2); for each block or sub CGH, calculating the corresponding replay sub-image hereafter called target wavefront data set (step 3); and generating for each target wavefront data set a second constrained modulation computer generated hologram wherein that second CGH is modulated within constrained values (step 5); and combining the plurality of second constrained modulation computer generated holograms to provide a third complete constrained modulation computer generated hologram (step 6).

Abstract: The invention relates to a method for displaying three-dimensional images. In the method light beams (Le) are associated to several different screen points (P) of a screen (20). The light beams (Le) produce different views associated to different emission directions (E). The emission directions (E) are associated to the individual screen points (P). The light beams (Le) are generated by projecting light beams (Ld), according to the angle of the adjacent emitting directions. According to the invention, light beams (Le) without viewing direction information are generated, essentially simultaneously, with pixels (Cd) having different co-ordinates. These pixels (Cd) are pixels of a two-dimension display (50), and they are associated to different emitting directions (E) of the appropriate screen points (P).

Abstract: An optical member 7 is bonded, at its rear side 7b, to a holographic stereogram 6. The front side 7a of the optical member 7 consists of parallel triangular prisms. Illumination light 9 is applied to the front surface 7a of the optical member 7 at a predetermined angle of, for example, 60°. The optical member 7 is made of, for example, optical glass or transparent plastic. Each triangular prism has an incidence surface 8, to which the illumination light is applied at right angles. The illumination light is applied to the interface 22 between the optical member 7 and the holographic stereogram 6, at an incidence angle ? of, for example, 60°, thereby to suppress surface reflection of the illumination light 9 at the interface 22.

Abstract: An optical member 7 is bonded, at its rear side 7b, to a holographic stereogram 6. The front side 7a of the optical member 7 consists of parallel triangular prisms. Illumination light 9 is applied to the front surface 7a of the optical member 7 at a predetermined angle of, for example, 60°. The optical member 7 is made of, for example, optical glass or transparent plastic. Each triangular prism has an incidence surface 8, to which the illumination light is applied at right angles. The illumination light is applied to the interface 22 between the optical member 7 and the holographic stereogram 6, at an incidence angle ? of, for example, 60°, thereby to suppress surface reflection of the illumination light 9 at the interface 22.

Abstract: A method of rendering image data for full parallax autostereoscopic displays. The method is based on a double frustrum camera technique, where two cameras provide image data from opposing sides of an image plane. The near clipping plane is located on the image plane. The distance between the near clipping plane and the eyepoint of the camera frustra is adjusted to minimize or avoid clipping.

Abstract: A holographic imaging system and method includes a radiation source for generating radiation. A data base has a set of elements, each element is indicative of a trajectory of a light ray exiting a point in a recorded scene. A spatial light modulator is receptive of the radiation from the radiation source and the elements of the data base mapped to the spatial light modulator, thereby projecting from the spatial light modulator an optical signal in the nature of a two dimensional bitmap of the recorded scene. A diffractive optical element includes a set of basis fringes receptive of the projected optical signal from the spatial light modulator for diffracting the optical signal in a specified direction. A multiplexer is receptive of the elements of the data base for multiplexing the elements of the data base to the spatial light modulator. A timing device synchronizes multiplexing the elements of the data base to the spatial light modulator and diffracting the optical signal in a specified direction.

Abstract: The invention provides systems and methods for generating and displaying computational holographic stereograms having a hologram surface and a spatially distinct image surface. A three-dimensional object or scene is captured or synthesized as a stack of views. The holographic stereogram is computed by obtaining a diffractive fringe vector e and a pixel slice v through the stack of views, and generating the holopixel representation f=ev. The holographic stereogram is displayed using one or more image surfaces that are spatially distinct from the hologram surface. the surfaces can be any two-dimensional structures defined on a three-dimensional space, including, but not limited to planar, cylindrical, spherical, or other surfaces. The holographic stereograms are adjustable through variations in an image surface depth, an image surface resolution, a number of image surfaces, and a scene parallax resolution.

Abstract: An optical member 7 is bonded, at its rear side 7b, to a holographic stereogram 6. The front side 7a of the optical member 7 consists of parallel triangular prisms. Illumination light 9 is applied to the front surface 7a of the optical member 7 at a predetermined angle of, for example, 60°. The optical member 7 is made of for example, optical glass or transparent plastic. Each triangular prism has an incidence surface 8, to which the illumination light is applied at right angles. The illumination light is applied to the interface 22 between the optical member 7 and the holographic stereogram 6, at an incidence angle ? of, for example, 60°, thereby to suppress surface reflection of the illumination light 9 at the interface 22.

Abstract: A distributed system for producing holographic stereograms (holograms). A data acquisition station is typically remote from image processing, printing, and replicating stations. The data acquisition station is designed to maximize customer convenience, and may be the customer's own personal computer. The data acquisition station is further designed to accept a wide variety of source data and to perform whatever processing is required to deliver image data to the image processing station in an acceptable format. The data acquisition station further has processing capability to display preview images, which may be assembled by programming executing at the data acquisition station or downloaded from a server.

Abstract: An image exposure recorder for exposure-recording a holographic stereogram image or a hologram image on a recording medium for hologram. The recorder has an inverse correction system for rotating the polarization plane of a reference light (R) by means of a half-wave plate (11), directing the reference light (R) to a hologram recording medium (3), and measuring the intensity of a part of the reference light (R) transmitted through a polarizer (12) out of the reference light (R) transmitted through a part of the area of the hologram recording medium by means of a photodetector (13). In the inverse correction system, the angle of rotation of the half-wave plate is so determined that the intensity of the reference light (R) determined by the photodetector may be minimum or maximum.

Abstract: Certain types of holographic recording materials can be used to updateably record holographic stereograms formed when fringe patterns are generated through interference of an object laser beam containing image information with a reference laser beam. In this manner, calculation of fringe patterns is avoided, and instead perspective information is computed for a scene or object to be displayed, the information is downloaded to display hardware such as a spatial light modulator, and fringe patterns are subsequently generated through interference of an object laser beam containing this information with a reference laser beam in the classic hologram recording scheme. Previously recorded holographic stereograms or component hogels are updated by erasing the stereograms or component hogels and recording updated stereograms or component hogels, or by recording updated stereograms or component hogels in a separate portion of the holographic recording material.

Abstract: Angle of incidence of reproducing light with respect to a hologram or a holographic stereogram is adjusted so that a reproduced image can be repetitively viewed without requiring the viewer to move his or her viewpoint. The components of the image reproducing apparatus can be roughly classified into a power supply unit equipped with a power supply for generating a driving power and various types of electric circuits, a light source unit equipped with light emitting diodes and the like, a supporting unit for supporting the light source unit, and a holographic stereogram display unit for holding the holographic stereogram and displaying an image. In this image reproducing apparatus, the light source unit is swingably or turnably moved repetitively with respect to the holographic stereogram so that the reproducing light has angle of incidence changed on the holographic stereogram, thus allowing change of viewed image.

Abstract: An illuminated colored display device provides a 360-degree viewable hologram, having the properties of a distortion free, monochromatic or full-color reconstruction from a single white light source, an extended vertical viewing aperture, and extended moving scene. These advantageous properties are provided by a rotating display device and a type of “synthetic” hologram composed of movie film frames or digital information. Each color component hologram consists of an array of noncontiguous small dots or thin stripes so that the three-color component holograms may be intermeshed without overlap of the dots or stripes. The component holograms themselves are vertically focused so that the composite hologram is white light viewable. The disclosed method includes the provision of a novel optical film holder and transport system.

Abstract: A set of enhanced apparatuses and a computer integrated processes are provided for creating large scale 3D integral photography images. A large number of mini projectors in a grid on top of each other and beside each other, are exposed individually with a computer calculated reverse (pseudoscopic) perspective image. The curved photo layer inside the projectors obtains sharp high resolution images through the achromatic behavior of the lens system. A guided back light system directs the light from the back through the diaphragm apertures.

Abstract: Between a spatial beam modulator for modulating an object beam and a one-dimensional diffuser plate for diffusing the object beam modulated by the spatial beam modulator in a one-dimensional direction, there is arranged an object projection optical system for processing the object beam modulated by the spatial beam modulator in such a manner that, in the one-dimensional direction of the one-dimensional diffuser plate, images displayed by the spatial beam modulator are formed on the one-dimensional diffuser plate, and, in a direction substantially orthogonal to the one-dimensional direction, the object beam is condensed onto a hologram recording medium. In the one-dimensional direction of the one-dimensional diffuser plate, the images displayed by the spatial beam modulator are formed on the one-dimensional diffuser plate, whereby blurring of the images with the one-dimensional direction as a non-parallactic direction can be suppressed.

Abstract: An improvement to the above described techniques for producing a holographic stereogram. The present invention uses a hologram lens in the process of creating the holographic stereogram, and also uses Fourier transforms of the images for projection onto the recording medium, not the images themselves. A lens between the generated images and the recording medium performs the inverse Fourier transform to convert the image back into a normal image.

Abstract: Pre-sensitization techniques can be used in conjunction with holographic recording materials to allow high quality holographic stereograms to be recorded in those holographic recording materials using pulsed lasers. Additional hologram production system hardware and software designs for use with pulsed lasers are disclosed.

Abstract: A parallax image string pickup apparatus can attract the gaze of the person being shot to make it stable without making the person nervous about the camera operation when the person is shot from a plurality of different angles and, at the same time, provide the person or object 31 with necessary information for the shooting operation including the position of the person in the frame of the viewfinder of the camera of the camera unit 32 and other shooting conditions. The parallax image string pickup apparatus 1 includes a camera unit 32 screened from the object 31, and a half mirror 40 is arranged between the camera unit 32 and the object 31. As the half mirror 40 shows an image of the object 31, the gaze of the object 31 is attracted to the half mirror 40 before and during a shooting operation.

Abstract: A holographic stereogram printing system to print holographic stereograms with good efficiency and no drop in the operating rate of the imaging system and holographic printer. An imaging system control section of an imaging system comprises an operating section that along with controlling the operation of the camera according to the desired selection of the user such as imaging method, image size selection or image layout, also creates an information management file for the base image based on the control information. A holographic stereogram printer prints out a holographic stereogram according to the information management file provided along a transmission path.

Abstract: A stereogram that consists of a plurality of rows of horizontally repeated text, words, symbols, or designs displayed on an object having a non-planar surface. The repeated text, words, symbols, or designs generally differ from row to row and are horizontally and differentially spaced apart. The elements of the image displayed are perceived to float in space in 3-dimensions as if parts of the image were located on different planes at different distances from the viewer when the point of convergence of the viewer's line of sight lies either in front of or beyond the actual plane of the displayed image. Application of the present invention, the object may be continuously rotated in one direction producing a continuous animated loop. Further, the curvature of the object provides an infinite number of fixed viewing angles. As a result, the viewer is able to experience the stereogram in a way not possible when displayed on a flat surface.

Abstract: An optical member 7 is bonded, at its rear side 7b, to a holographic stereogram 6. The front side 7a of the optical member 7 consists of parallel triangular prisms. Illumination light 9 is applied to the front surface 7a of the optical member 7 at a predetermined angle of, for example, 60°. The optical member 7 is made of for example) optical glass or transparent plastic. Each triangular prism has an incidence surface 8, to which the illumination light is applied at right angles. The illumination light is applied to the interface 22 between the optical member 7 and the holographic stereogram 6, at an incidence angle &thgr; of, for example, 60°, thereby to suppress surface reflection of the illumination light 9 at the interface 22.

Abstract: An illuminating optical system 36 evenly spreads an object beam L3 split from a beam splitter 34. When a control computer sends a number of images in the parallax direction, a spatial light modulation section (liquid crystal) 38 displays these images in that number of divisions under control of the control computer. A superposed projection optical system 39 superposes and projects light beams passing through the spatial light modulation section 38. A beam-condensing projection optical system 41 condenses a projected image's beam from the superposed projection optical system 39 in the parallax direction and forms this image in the non-parallax direction on the surface of a hologram recording medium 42.

Abstract: A pixel element for a 3D display, wherein multiple substantially collimated controllable light beams are emitted in multiple directions, with each light beam associated with a predetermined viewing direction. A set of substantially point type sources are individually addressable and are arranged in a line. The light sources are serially addressed; and the light from each source is imaged in a collimated light beam and deflected in a predetermined individual deflection direction.

Abstract: An optical member 7 is bonded, at its rear side 7b, to a holographic stereogram 6. The front side 7a of the optical member 7 consists of parallel triangular prisms. Illumination light 9 is applied to the front surface 7a of the optical member 7 at a predetermined angle of, for example, 60°. The optical member 7 is made of, for example, optical glass or transparent plastic. Each triangular prism has an incidence surface 8, to which the illumination light is applied at right angles. The illumination light is applied to the interface 22 between the optical member 7 and the holographic stereogram 6, at an incidence angle &thgr; of, for example, 60°, thereby to suppress surface reflection of the illumination light 9 at the interface 22.