Abstract: A laser source and a converging lens are provided so that a laser beam emitted from the converging lens travels substantially parallel to the surface of a hologram disc. A incidence mirror is provided for causing the laser beam emitted from the lens to fall incident on the hologram disc at an angle of incidence of about 45 degrees. By merely moving or rotating the incidence mirror, the position of and the angle of incidence of laser beam to the hologram disc can be easily adjusted.

Abstract: In a device for perforating cigarette paper strips, a row of adjacent optical elements (28) is disposed in the ray path of a laser beam deflected by a rotating mirror (12). Each of the optical elements includes a diffractive optical element (DOE) (24'; 24"; 24'") and a convergent lens (18'; 18"; 18'"). A parallel bundle of laser rays hits the surface of the DOE, and the DOE emits one or more bundles of rays with a desired configuration. The convergent lens produces therefrom in the plane of the cigarette paper strip (20) one or more focal spots, for example two or four mutually offset focal spots (22a, 22b) or a ring focus, so that one can form not only microperforations by individual focal spots but also macroperforations by applying energy to only the peripheral area of a macroperforation rather than the entire perforation area.

Abstract: A holographic scanner for scanning a surface with a light beam is provided. The holographic scanner includes a light source for emitting light used as the light beam, a front hologram for diffracting the light emitted from the light source to produce a first diffracted beam, a rotary hologram disk having a disk plane and rotatable around an axis thereof vertical to the disk plane, the rotary hologram disk including a plurality of scanning holograms arranged on the disk plane in a circumferential direction, the scanning holograms diffracting the first diffracted beam to produce a second diffracted beam, and a rear hologram for diffracting the second diffracted beam to produce a third diffracted beam, the third diffracted beam being used as the light beam for illuminating the scanning plane.

Abstract: An optical-scanning system including a laser, a multi-faceted, rotational scanning mirror, and system-monitoring laser safety structure operatively and informationally connected respectively to the laser and to the mirror and the drive motor for the mirror for altering the effective power output of the laser in response to current operational status of the system as determined by current operational status of the rotating mirror. The safety structure enforces on the laser a duty cycle of operation which is less than 100-percent, causes the laser to power down to a low "sleep" operating level at times other than during a normal scanning sweep, de-powers the laser entirely if either the drive motor for the mirror is not enabled or the rotational speed of the mirror is below full normal operating speed, and also positively de-powers the laser when a user shuts down the system.

Abstract: A scanner configured to provide a two-dimensional scan of a radiation beam moving along the path, including two deflectors and a scan lens located downstream in the path of the beam from the deflectors and separated from the farthest deflector by air equivalent distance at least equal to the focal length of the scan lens.

Abstract: A method for fabricating a holeless hologon disk includes the steps of relatively positioning a disk assembly and a drive shaft assembly in closely spaced relation with the planar surface of the disk normal to the drive shaft's rotational axis. Adhesive is applied between the assemblies and allowed to fix while the relative assembly positions are maintained. In one construction fabricated by such method, the disk assembly comprises a flanged coupling attached to a planar glass disk with compliant adhesive.

Abstract: An optical scanning device including a semiconductor laser and a scanning optical system which transmits a laser beam emitted from the semiconductor laser and scans the laser beam on a photosensitive drum. The scanning optical system includes at least one hologram having relief on at least one surface with the ratio h/P of the depth h and the minimum pitch P of the relief being set to about 1 or less in an area of the hologram surface the laser beam irradiates.

Abstract: An image scanning apparatus can obtain, using a simple optical detection system, original sheet information including size and displacement information of an original sheet before an image scanning operation starts. The image scanning apparatus comprises a single beam emitting unit for emitting a coherent first beam. A deflecting unit deflects the first beam so that the first beam traces a predetermined scan line on a plane including a surface of the original sheet. A second beam is generated by reflection of the first beam at the surface of the original, and the second beam is input to the sensing unit via the deflecting unit. The original sheet information is obtained in accordance with the detection of a sharp change in the intensity of the second beam received by the sensing unit with reference to the scanning position of the first beam.

Abstract: A laser beam passes through two holograms or through a hologram twice to reduce the ratio .lambda./d so that P-polarized light, as well as S-polarized light, can be diffracted with high diffraction efficiency and uses a hologram or holograms formed on a base plate and facilitates the separation of a stamper from the base plate in producing replicas of the hologram. A laser beam (5) passes through two holograms formed on a transparent base plate or through a hologram formed on a transparent base plate twice. The ratio .lambda./d, where .lambda. is the wavelength of the laser beam and d is the grating constant of the hologram, is in the range of 0.4 to 1.1.

Abstract: A double bounce facet tracking polygon in which a reflective mode replicated diffraction grating element on a flat facet on the double bounce facet tracking polygon is used to provide a small angle deflection which is used in a passive facet tracking system.

Abstract: Scanning device for optically scanning symbol codes, such as bar codes, comprising a laser source for producing a scanning beam, a detector for detecting light backscattered by the scanned symbol codes, first and second rotatable deflection elements for both transmitting and deflecting the scanning beam so as to generate a scanning pattern, and drive devices for rotating the first and second deflection elements around a first and second axis of rotation, respectively, in which scanning device the scanning beam when impinging upon the first deflection element does not coincide with at least one of both axes of rotation.

Abstract: An optical data storage system includes a pivotally mounted hologram. Rotation of the hologram results in beam displacement at the optical medium for purposes of fine tracking. The hologram is designed and positioned relative to the focusing lens, such that the beam always passes through the center aperture of the lens even when the beam is displaced at the optical medium. Thus, the beam is not truncated at the focusing lens and loss of light and aberration problems are prevented.

Abstract: A three-dimensional image display device which comprises a holographic plate having a plurality of holograms divided in correspondence with rotational angles, the holographic plate being exposed so that when light is irradiated, each of the holograms forms a point image at a different position in a depth direction of the holographic plate; a drive unit for rotating the holographic plate; a light irradiating unit including a plurality of light sources arranged substantially in a straight line so that the light sources are kept at substantially equal distances from the holographic plate, for irradiating the holographic plate with light from the light sources; and a controller for controlling the drive unit and lighting operations of the plurality of light sources of the light irradiating unit in accordance with a signal indicative of a three-dimensional image to be displayed so as to control lighting of a plurality of point images formed in a three-dimensional space, whereby a three-dimensional image can be obt

Abstract: A holographic grating element is provided which enables tracing different scan lines. The element is divided into a plurality of sectors. A first grating pattern is provided which diffracts a beam in one direction, and a second grating pattern is next to the first and diffracts the scan beam in the reverse direction. Sectors can be produced with different sector sizes to enable scanning at different rates in the reverse direction, or in successive scans in the same direction. Angle relationships are described to produce diffraction patterns for a desired relationship between disc rotation and the angle of the scan line.

Abstract: An internal drum plotter in which a multiple focal point holographic element receives respective modulated light beams, one for each focal point, to focus the light beams on a light sensitive medium on the internal surface of the drum. The holographic element is rotated to trace the modulated light beams in separate, respective lines on the light sensitive medium.

Abstract: Centered monofacet deflector systems having a dipole laser beam scanning pattern (dual scanning beams which propagate in opposite directions) enables both the scan rate and the scan duty cycle of the scanning system to be doubled over deflectors which produce only one beam. The deflector may be a non-disc plane diffraction grating (NPDG) deflector or a dual reflecting cube (DRC) deflector having polarization sensitive beam splitting characteristics. The input beam polarization contains or is generated to contain orthogonally polarized components which are reflected or diffracted to produce one of the dual scanning beams and a transmitted beam through the element and retroreflected with the proper polarization to be deflected at the element to produce the other scanning beam thereby providing the capability of two simultaneous or sequential scan lines for every revolution of the deflector element.

Abstract: An image scanning apparatus can obtain, using a simple optical detection system, original sheet information including size and displacement information of an original sheet before an image scanning operation starts. The image scanning apparatus comprises a single beam emitting unit for emitting a coherent first beam. A deflecting unit deflects the first beam so that the first beam traces a predetermined scan line on a plane including a surface of the original sheet. A second beam is generated by reflection of the first beam at the surface of the original, and the second beam is input to the sensing unit via the deflecting unit. The original sheet information is obtained in accordance with the detection of a sharp change in the intensity of the second beam received by the sensing unit with reference to the scanning position of the first beam.

Abstract: Optical apparatus that condenses illuminating light into a narrow formatted band of light that follows activated lines down a light valve as it is driven. The present invention is a telecentric illumination scanning system that comprises an input lens group, a rotatable or oscillating reflective scanner, an output lens group and a polarizing element. The input lens group transmits light provided by a light source to the scanner, which is reflected therefrom and is directed to the output lens group. The light transmitted by the output lens group is polarized by the polarizing element and applied to the light valve. The input and output lens groups focus the light provided by the light source into a relatively narrow band of light that is scanned by the rotatable or oscillating scanner across the face of the light valve. A telecentric light zone is formed in a predetermined space between the output lens group and the light valve.

Abstract: A three-dimensional image display device which comprises a light source; a hologram divided into a plurality of divided areas and exposed so that point images are formed at different positions in a three-dimensional space in the respective divided areas when the light from the light source is irradiated; a hologram driver unit for driving the hologram such that light from the light source is selectively entered into one of the plurality of divided areas and; a control unit for controlling the lighting up of the point images formed in the three-dimensional space in correspondence to a three-dimensional image signal by controlling the hologram and the light source in accordance with the three-dimensional image signal to be displayed, whereby a three-dimensional image is obtained by the hologram with the simple-configured device.

Abstract: A three dimensional display having a rotating screen, preferably helical in shape, a light source providing a beam of light and a holographic pattern deflecting the beam of light to predetermined points on the screen. The light is modulated, preferably by the holographic pattern. The holographic pattern rotates with the same angular velocity as the screen. The holographic pattern comprises a plurality of concentric circles, each of the circles comprising a plurality of cells, each of the cells representing a point on the screen.

Abstract: A holographic disk mounting system and method is disclosed utilizing a compressible O-ring which eliminates the clearance between the spin motor shaft and the holographic disk. The holographic disk has an axial bore with a diameter slightly greater than the diameter of the spin motor shaft. A compressible O-ring is placed around the spin motor shaft and then the holographic disk is mounted thereon with the O-ring and O-ring surrounded portion of the spin motor shaft positioned within the axial bore of the holographic disk. The O-ring is axially compressed to radially expand the O-ring thereby eliminating the clearance between the spin motor shaft and the bore of the holographic disk. Thereafter, the holographic disk is secured to the motor shaft with the O-ring remaining in a compressed state.

Abstract: A device for use in a system of hologon deflection of a laser beam having a wavelength .lambda. at a rotating angle .theta..sub.R to produce a scan line. The device comprises a prism having a grating on at least one surface. The prism is positioned to deflect the scan line after hologon deflection of the laser beam. The prism has an apex angle between scan line intersecting surfaces of .theta..sub..alpha.. The grating has a grating spacing D. Deflection of the scan line by the angle .theta..sub..alpha. is designed so that it is equal to the deflection of the scan line by the grating. This produces a scan line having bow of less than 1/600 of the bow of the scan line without the prism and effectively eliminates wobble. The range for the apex angle .theta..sub..alpha. may be from about 1.degree. to about 30.degree., and preferably from about 2.degree. to about 6.degree.. The grating spacing ranges from about 0.0001 to about 0.001 millimeter.

Abstract: A scan start detecting device for a laser beam printer, comprising a wave length variation correcting unit arranged between a scanning unit including a scan disc hologram and a scan start detecting unit including a detector, the wave length variation correcting unit including a scan start hologram. The scan start hologram, which is a write hologram, serves to positional errors caused by a variation in wavelength, together with a pre-scan hologram arranged in front of the scan disc hologram. The correction of the scan start point is achieved, without using the cylindrical lens requiring a double surface finishing work. For the correction of the scan start point, the write hologram is used, which has the same function and yet inexpensive. Accordingly, the manufacture cost can be reduced. Where the write hologram is added with a read function, the performance thereof can be more improved. It is also possible to reduce the overall optical path of scan start beams.

Abstract: An image processing apparatus is provided to have a spatial light modulator onto and from which an image data is written and read, a digital reading system for digitally reading an image data written on the spatial light modulator, a processing unit for processing the read image data, and a digital writing system for digitally writing the processed data on the spatial light modulator. The digital reading or writing system serves to two-dimensionally move a laser beam on the spatial light modulator for reading or writing an image data from or onto the spatial light modulator. The digital reading or writing system provides a hologram disk having hologram lenses located in a concentric or spiral manner. The hologram disk is arranged to deflect the laser beam vertically and horizontally for scanning the spatial modulating element.

Abstract: An optical system for a laser beam scanner, is capable of reducing the manufacturing cost by substituting a holographic optical element for a toric lens, comprising a light source for generating a laser beam, a rotary polyhedron for collimating the laser beam from the light source and focusing and reflecting the laser beam; and a compensating lens array, including a concave lens for receiving the laser beam from the rotary polyhedron and a convex lens attached with a holographic optical element, for compensating the laser beam reflected from the rotary polyhedron and scanning the compensated laser beam to a drum.

Abstract: A method of recording holograms for use in optical scanners comprises the steps of generating a reference beam by means of a reference source, generating an object beam by means of an object source, and illuminating a photosensitive surface with both said object beam and said reference beam, wherein said object beam is divergent in a first direction and non-divergent in a second direction.

Abstract: An optical scanning system including an aiming system which is particularly suitable for handheld scanners where the outgoing light is scanned over a desired angle in a scan plane. The aiming system includes a light source generating an optical beam along an outgoing optical path toward an object to be scanned; a detector for detecting light reflected off the object; an oscillating scan mirror in the outgoing optical path directing light toward the object along a scan plane; and a diffractive optical module positioned in the outgoing optical path adjacent the scan mirror, the diffractive optical module having a pair of diffractive optical elements separated by an aperture, the diffractive optical elements positioned on either side of an aperture along the scan plane, each diffractive optical element de-scanning the portion of the optical beam passing therethrough to form an aiming light beam.

Abstract: An optical beam scanning apparatus includes one rotatable hologram which is rotatable about an axis, and at least two laser beam sources which emit laser beams. The rotatable hologram is provided with at least two hologram areas whose number corresponds to the number of the laser beam sources, so that the laser beams emitted from the respective laser beam sources are made incident upon the respective hologram areas. Each of the hologram areas is provided with a plurality of hologram facets which are concentrically arranged with respect to the axis of rotation of the rotatable hologram to emit laser beams of the same F number. The hologram areas having different numbers of hologram facets having different F numbers.

Abstract: A grating having holographic properties is employed in a pixel clock for a raster-output scanner. A pilot beam, off-axis from the writing beam creating a latent image on the photoreceptor, is focused on the grating. The grating is adapted to direct a portion of the pilot beam to a photodetector in a fixed point location. The holographic properties of the grating ensure that a wave associated with a reflected interference pattern is always directed at the photodetector throughout the scan path of the pilot beam.

Abstract: An information reader, including a light source for emitting a light beam. A photo-detector detects the light beam after it is reflected from a bar code. A rotatable circular hologram disk scans the light beam in two dimensions and guides the light beam reflected to the photo-detector. A prism deflects the light beam emitted from the light source toward the circular hologram disk. A housing receives the light source, the photo-detector the circular hologram disk and the prism therein. The light source and the prism are integrally detachable from the housing. It is thus easy to adjust the incidence angle of the light beam on the circular hologram disk.

Abstract: An optical synchronization system uses a stationary binary diffractive optical element and a rotating disc with alternating binary diffractive optical elements and blocking elements to create a moire pattern of a synchronization signal for a pixel clock.

Abstract: An optical scanning device utilizing a source of optical energy such as laser light backscattered from the earth's atmosphere or transmitted outward as in a lidar, a rotating holographic optical element having an axis of rotation perpendicular to the plane of its substrate, and having a stationary focus which may or may not be located on its axis of rotation, with the holographic optical element diffracting the source of optical energy at an angle to its rotation axis enabling a conical scanning area and a motor for supporting and rotating the rotating holographic optical element.

Abstract: An optical scanner suitable for use with a bar code reader includes a light source for generating a laser beam, a laser beam scanning device, a scanning pattern generating optical system, and a signal light condensing optical system for deflecting scattered signal light scattered by an object to be read to introduce the light to a photo-detector. The scanning pattern generating optical system or signal light condensing optical system includes strips of planar reflective holograms disposed substantially in parallel with each other in one plane to produce a reflection beam having an angle of reflection which is different from an angle of incidence of the laser beam thereon. Another embodiment discloses a condenser integrated with one of plane mirrors for deflecting the scan beam to form a hologram module of the reflection type. The scanner is a miniaturized apparatus as a result of the reflection holograms.

Abstract: An optical scanner suitable for use with a bar code reader includes a light source for generating a laser beam, a laser beam scanning device, a scanning pattern generating optical system, and a signal light condensing optical system for deflecting scattered signal light scattered by an object to be read to introduce the light to a photo-detector. The scanning pattern generating optical system or signal light condensing optical system includes two reflective holograms disposed substantially in parallel with each other to produce a reflection beam having an angle of reflection which is different from an angle of incidence of the laser beam thereon. The scanner is a miniaturized apparatus as a result of the reflection holograms.

Abstract: An optical scanning device which includes a laser light source, an aspheric lens for converging a laser beam emitted from the laser light source, and a reflection type holographic disk for diffracting and scanning the laser beam passing through the aspheric lens.

Abstract: Laser beam scanners having a polarization sensitive beam deflecting surface (specifically a monofacet nondisc plane diffraction grating (NPDG) monofacet deflector and a dual reflection monofacet polarization sensitive deflector that incorporates a polarizing beam splitter cube) achieve essentially 100% radiometric throughput efficiency while also achieving a scan beam intensity that stays constant over the total range of scan angles by using a circularly polarized incident beam and a quarter-wave retardation plate at the entrance aperture of the scanner assembly so that the quarter-wave plate rotates with the assembly. The quarter-wave plate has its optical axis oriented with respect to the incident beam so that it converts the incident circularly polarized beam into a linearly polarized beam having a polarization direction that maximizes the radiometric throughput efficiency of the scanner assembly.

Abstract: Optical systems are disclosed which are capable of generating and rapidly changing time delays of electrical signals for true time delay beam formation and beam steering. The systems utilize an interferometer configuration. A first optical modulator and a Fourier transform lens define a Fourier transform plane in a first leg of the interferometer. In a second leg of the interferometer, a second optical modulator provides beam steering to a prism stack, which produces a set of plane reference waves having a range of orientations required to generate a desired range of time delays. Preferably the optical modulators are acousto optic Bragg cells. Alternatively, a holographic optic element could be used in place of the prism stack.

Abstract: An optical information reading apparatus for optically reading information recorded on a recording medium with a laser light beam emitted from a light source. The apparatus comprises a hologram device for receiving at its center portion a laser light beam. The hologram diffracts the received light so as to produce a first diffracted light beam and is arranged to receive at its entire surface light to be reflected from the recording medium and to diffract the received light so as to produce a second diffracted light beam. This hologram device is arranged to be driven by a motor so as to move the first diffracted light beam for a scanning operation. Also included in the reading apparatus is a reflection assembly for reflecting the first diffracted light beam from the hologram device toward the recording medium and further for reflecting light reflected from the recording medium toward substantially the entire surface of the hologram device whereby the hologram device produces the second diffracted light beam.

Abstract: An optical beam scanning apparatus including a semiconductor laser, a first lens which converts a divergent beam to a parallel beam, a liquid crystal display for two-dimensionally modulating the intensity of the parallel beam and having a matrix of vertical and horizontal electrodes which constitute modulating elements at the crossings of the electrodes, a second lens which converges the parallel beam incident thereon to a focal point of the second lens system, a spatial optical modulator located at the focal point of the second lens system to convert the converged beam to a parallel wave, and a third lens which produces a beam spot from the parallel wave incident thereon at a focal point of the third lens.

Abstract: A system that provides a structure which makes use of a recording geometry in which no significant Seidel induced aberrations arise. The recording geometry results in a pattern recorded on a photosensitive surface, thereby creating the hologram on the scanning disc. Reconstruction of the recorded object may be made by exposing the scanning disc to substantially monochromatic light. The hologram on the scanning disc not only directs the reconstruction beam, but also focuses it. An optical element may be used during reconstruction to correct for bow and linearity, and also optimize flatness of the focal plane. Reconstruction also involves achromatization, or correction of beam placement because of mode hops or drift in laser frequency. The reconstruction comprises both pre-scan holograms and post-scan holograms. Recording of the post-scan hologram is achieved with a plurality of lenses which possess different collimating properties in the vertical and horizontal planes.

Abstract: A dual, simultaneous beam scanning system for simultaneously scanning two individually modulated adjacent scan lines on an internal drum imaging surface uses a deflector which varies the angular orientation between combined orthogonally polarized beams so that one of the beams rotates about the other in synchronism with the angular position (the distance between start of scan) along the scan lines around the drum imaging surface. Signals from both a beam position sensing photodetector array and from a shaft encoder on the deflector unit, such as a Hologon deflector, controls the deflection of one of the orthogonally polarized beams so as to maintain the spacing and prevent crossovers of the adjacent scan lines and also reduce differential bow. Differential bow may be corrected both in the internal drum configuration and in a flat field imaging system using plural beam scanning. The scan lines can overlap so as to provide high resolution imaging at a rate of the order of hundreds of scan lines per second.

Abstract: A three-color laser scanner using a holographically-generated plane linear grating disk (hologon). The disk includes peripherally-arranged facets having identical multiplexed diffraction gratings. Each multiplexed grating is formed from plural superimposed interference patterns accumulated by multiple exposures to light from a single monochromatic laser beam source. The multiplexed grating is optimized to diffract certain light wavelengths in a single, multichromatic (plural wavelength) input laser beam. The diffracted output beam comprises respective wavelength beam components that simultaneously scan in collinear fashion. Modulation of the plural wavelength components in the incident beam allows the output beam to scan expose a multicolor image at the image plane.

Abstract: A calibration method and apparatus is disclosed that includes a power stabilized laser diode to generate a laser beam that is passed through the hologon scanner to be calibrated and a mechanism for measuring the power intensity of the laser beam at a plurality of positions at an exposure plane for each facet of the hologon scanner. The measured light levels are converted to correction factors that are stored in a corresponding programmable read only memory (PROM) as a function of facet number and scan position. The hologon scanner and its corresponding programmable PROM are then installed in a laser scanning apparatus. The laser scanning apparatus adjusts the output of its light source in accordance with the correction factors stored in the PROM in order to compensate for variations in the light transmission efficiency of the facets of the hologon scanner.

Abstract: An electronic autostereoscopic display that presents 3D images through the use of horizontal parallax is disclosed. The device disclosed presents a 3D image, viewable over 360 degrees or less, without the need of special viewing glasses. The image is created electronically and in real-time, thus it can immediately display data gathered remotely, as in live 3D television, and similar applications. The autostereoscope consists of a cylindrical holographic optical element (HOE) which is spun about its axis of symmetry by a motor, light sources such as lasers emit light beams incident on the HOE, and electronic circuitry modulates the lasers according to data received and the angular displacement of the HOE. The HOE consists of 2 basic types of holograms which perform 2 different functions. The first type of hologram performs two dimensional raster scans onto the second type of hologram.

Abstract: A dual, simultaneous beam scanning system for simultaneously scanning two individually modulated adjacent scan lines on an internal drum imaging surface uses a deflector which varies the angular orientation between combined orthogonally polarized beams so that one of the beams rotates about the other in synchronism with the angular position (the distance between start of scan) along the scan lines around the drum imaging surface. Signals from both a beam position sensing photodetector array and from a shaft encoder on the deflector unit, such as a Hologono deflector, controls the deflector of one of the orthogonally polarized beams so as to maintain the spacing and prevent crossovers of the adjacent scan lines and also reduce differential bow. Differential bow may be corrected both in the internal drum configuration and in a flat field imaging system using plural beam scanning. The scan lines can overlap so as to provide high resolution imaging at a rate of the order of hundreds of scan lines per second.

Abstract: An optical scanner has a light distributor rotating about an axis spaced from but parallel to the optical axis of at light source. Lenses are mounted on a carrier that rotates about the optical axis. The distributor and carrier rotate a the same angular velocity and are arranged so that the lens and associated distributor move across the media at the same time. By rotating the lens about the optical axis, the scanning beam remains in the central zone of the lens as it passes across the media.

Abstract: A light scanning system for moving a light beam across a straight surface. The system includes a laser light source, a rotating holographic disk deflection system, and a multielement F.theta. lens constructed entirely of holographic plates. The holographic plates are offset from each other in the beam path and have parameters which cause the holographic plates to optically cooperate with each other to produce uniform spot size and scan velocity. Specific construction parameters and methods are outlined along with particular materials and parameter ranges.