Abstract: For performing hologram recording or reproduction, an oscillation wavelength half value width ?? of a coherent light source satisfies a relationship of ??<?2/(S×2 sin ?), where a substantial hologram size is S, a substantial cross angle between reference light and signal light is ?, and the oscillation wavelength of the coherent light source is ?. Even when stray light is generated, the coherent light source can suppress generation of an unnecessary interference fringe due to the stray light, and stably record and reproduce holograms.

Abstract: A GaN-based semiconductor laser (1) emits first laser light of a single polarization and having a first wavelength. An optical resonator (30) includes a solid-state laser medium which is excited by incidence of the laser light and which oscillates second laser light having a second wavelength different from the first wavelength. A polarization switch (6) switches over at least one of polarization directions of the first laser light and the second laser light to thereby change the wavelength of laser light to be emitted from the optical resonator (30) or the intensity ratio between a plurality of laser light to be emitted from the optical resonator (30). With the above arrangement, a plurality of laser light can be used effectively.

Abstract: A multipurpose projector 100 is provided with a fiber bundle 6 including a plurality of cores fixedly arranged on an input plane and an output plane, laser beam sources 1r, 1g and 1b for emitting laser beams having directivities, an optical guide unit 2 to 5 for modulating the laser beams emitted from the laser beam sources 1r, 1g and 1b and guiding the modulated laser beams to the input plane of the fiber bundle 6, a projection lens 8 for enlarging and projecting the laser beams emerging from the output plane of the fiber bundle 6 to a display space 12, and a projection angle adjusting mechanism 7 disposed on the side of the output plane of the fiber bundle 6 for adjusting projection angles of the laser beams projected from the projection lens 8. Thus, the projector can have its projection space freely operated and enlarged to extend its application not only to image display, but also to illumination and decoration with colored light.

Abstract: The present invention provides a planar lighting device (1) including: a laser light source (12) which emits a linearly-polarized laser beam; an optical member (13) which receives the laser beam, then parallelize the laser beam, and emits the parallelized laser beam; and a first plate-shaped light guide (20) which receives the parallelized laser beam from an end face portion (20d) and emits the parallelized laser beam from a first major surface (20b). The first light guide includes an optical element (20a) which receives the linearly-polarized parallelized laser beam propagated through the first light guide and emits at least a part of the linearly-polarized parallelized laser beam in a direction substantially vertical to the first major surface. The present invention also provides a liquid crystal display device (3) using the planar lighting device (1) as a backlight lighting device.

Abstract: An image display device is provided with an image display unit for displaying an image visually recognizable by a viewer. The image display unit includes a sub-diffusion layer for diffusing laser light, a vibrator for vibrating the sub-diffusion layer, a primary diffusion layer for diffusing the laser light diffused by the sub-diffusion layer and a light shielding layer for cutting off outside light from a viewer side, wherein the primary diffusion layer and the light shielding layer are arranged at the viewer side of the sub-diffusion layer.

Abstract: A planar lighting device that applies light having high luminance with good monochromatic characteristics, and a liquid crystal display device using the same are provided. The planar lighting device (11) is provided with: a laser light source (12) that emits laser light beams of red, green and blue colors; at least one optical wave guide unit (14) that is placed in a plane state and is optically connected to the laser light source to propagate the laser light beams emitted from the laser light source; a planar light guide plate (15) that is arranged on a surface side of the optical wave guide unit, spreads the laser light beams propagating through the optical wave guide unit, and outputs the laser light beams from one of principal surfaces (21); and a plurality of light taking out units (19) that are arranged on the other principal surface of the light guide plate, and guide the laser light beams propagating through the optical wave guide unit to the light guide plate.

Abstract: It is aimed to provide an LCD backlight device and liquid crystal display that can suppress light quantity loss and ensure uniform brightness. An LCD backlight device 101 has a laser light source 1 that emits laser light, and a light guiding plate 3 that transforms the laser light from the laser light source 1 into linear laser light, and transforms the linear laser light into a planar laser light, and emits the planar laser light, and the light guiding plate 3 has a third side face 6 that transforms the linear laser light into the planar laser light by reflecting the linear laser light by a plurality of reflection surfaces that are formed along the entrance direction of the linear laser light.

Abstract: The present invention provides a hologram recording material which attains high refractive index change, high sensitivity, low scattering, environment resistance, durability, low dimensional change and high multiplicity, and is suitable for volume hologram recording; a process for producing the hologram recording material; and a hologram recording medium. A hologram recording material comprising a metal oxide matrix and a photopolymerizable compound, said metal oxide matrix having a halogen-containing organic group. The metal oxide matrix is formed by hydrolysis and polymerization reaction of a metal alkoxide compound, and said metal alkoxide compound includes a metal alkoxide compound represented by the following general formula (1): (RH)mM(OR)n??(1) wherein RH represents the halogen-containing organic group, R represents an alkyl group, M represents a metal atom, m represents 1 or 2, and m+n represents the valence of the metal atom M.

Abstract: A multilayer holographic recording medium that improves recording density and data transfer rates. The multilayer holographic recording medium, from which information is reproduced by a multilayer holographic memory reproducing apparatus, includes a plurality of deposited holographic recording layers. During recording, a reference beam is common to those holographic recording layers and an incident angle of an object beam is modulated for each holographic recording layer. During reproduction, a laser beam for reproduction having the same condition as that of the reference beam used for recording is projected thereonto, so that diffraction beams are simultaneously generated in the respective holographic recording layers to directions that are the same as incident directions of the object beam used for recording.

Abstract: In a personal identification system 10 for identifying a user on the basis of biometric information, a hologram is formed in a holographic recording portion 13 of an optical information recording medium 12. The hologram is provided by the interference between a reference beam subjected to spatial light modulation by record cryptographic identification information based on the biometric information of the user obtained by a biological information sensor 14 and an object beam. At the time of identification, an information processing device 16 makes validation cryptographic identification information from the biometric information directly obtained from the user, and a spatial light modulator 20 modulates a hologram reproduction reference beam by the validation cryptographic identification information. The right or wrong of a reproduced image is detected, and the leakage of the identification information is prevented.

Abstract: Disclosed is a liquid crystal display device, which is capable of reducing a required response speed and increasing a pixel aperture ratio, as compared with a field sequential driving scheme. A unit pixel of a liquid crystal display panel is made up of a first sub-pixel adapted to allow only any two of red, green and blue lights to pass therethrough, and a second sub-pixel adapted to allow only a remaining one of the red, green and blue lights to pass therethrough, wherein one frame of image is time-divided into n pieces (wherein n is an integer of two or more), and respective image information about the two lights are applied to the first sub-pixel during every duration of the 1/n frame, while applying image information about the remaining one light to the second sub-pixel during a duration of the one frame of image.

Abstract: Disclosed is a liquid crystal display device capable of performing image display with more adequate white level, during an operation of displaying an image which requires emphasizing white. A backlight illuminator for illuminating a liquid crystal display panel comprises a white light source adapted to generate white light, in addition to a laser source adapted to generate red light, blue light and green light. When an image to be displayed on a liquid crystal display panel requires emphasizing white, white light from the white light source is emitted to a liquid crystal display panel, in addition to red light, blue light and green light from the laser source. This makes it possible to display the image which requires emphasizing white, in the form of an image with more natural image quality.

Abstract: A laser image display comprising a laser light source emitting laser light, a beam deflector element for receiving laser light and deflecting its advancing direction, a beam deflecting element control section for controlling the degree of deflection performed by the beam deflector element, an optical integrator for receiving and guiding the deflected laser light to output from its outputting end face, a pseudo surface light source element for scattering the deflected laser light, and a modulation element for receiving and modulating the laser light scattered by the false surface light source element.

Abstract: A laser projector is provided with a laser light source (1); a two-dimensional light modulator (6) which modulates light from the laser light source (1); and a projection optical system (7) which projects images onto a display plane (10) by expanding the light modulated by the two-dimensional light modulator 6). Shift of a display position of the two-dimensional light modulation element (6) and shift of the projection optical system (7) are performed in synchronization with each other so that display positions of the images on the display plane (10) are made substantially identical to each other. Thereby, speckle noise is sufficiently removed, and high-grade images are displayed.

Abstract: A surface illumination apparatus is provided which includes a laser light source and a light guide plate upon which a laser beam emitted from the laser light source is incident through an end-surface portion and from which the laser beam is emitted through a main-surface portion on one side thereof. The laser beam is incident through an end-surface portion at an inclination angle to a main-surface portion on the other side which faces the one main-surface portion of the light guide plate, undergoes a change in the optical-path direction thereof by the other main-surface portion, is incident on the one main-surface portion and is emitted as a substantially parallel beam from the one main-surface portion.

Abstract: A method of recording data on a double-layer optical recording medium having a recording layer with high light transmittance is provided. A laser beam is modulated to emit a pulse series of laser including a write pulse of a write power and a cooling pulse of a bottom power, so as to encode and write data to be recorded as recording marks of a length nT along a track of the recording layer, where n is an integer and T is one clock cycle. An nT recording mark is formed using (n?1) write pulse(s), and when forming a recording mark of 4 T or longer, a cooling pulse with a pulse width of 0.8 T to 2 T is inserted before the last write pulse. Recording marks are thereby accurately formed without heat interference between consecutive recording marks and cross erase between recording marks of adjacent tracks.

Abstract: A light source device is provided with a coherent light source for emitting the coherent light, and a pattern changer for changing an interference pattern of the coherent light on a surface of the illumination object. The pattern changer includes a photorefractive crystal which is arranged between the coherent light source and the illumination object and on an optical path of the coherent light and exhibits a photorefractive effect, and a changer for changing at least one of a light intensity distribution, a polarization direction, a wavelength and an intensity of coherent light incident on the photorefractive crystal. The illumination object is illuminated with the coherent light.

Abstract: Provided is a hologram retrieval method and a holographic recording and reproducing apparatus for preventing an increase in SNR, a decrease in retrieval accuracy, or the retrieval itself from being made impossible, which would otherwise occur because of a small size of data used for retrieval. Digital information is recorded on a holographic recording medium as data pages DP formed of a two-dimensional bit map image with each page being multiplexed. The data page DP is divided into a plurality of equal data blocks DB11 to 13, DB21 to DB23, and DB31 to DB33, and each data block DB is provided with a data image that is encoded by an encoding method for providing a certain number of ON pixels within each data block DB. A spatial light modulator allows the to-be-retrieved data image to be encoded by the encoding method and displayed as block information on a retrieval data block associated with the data block, and a signal beam to be thereby modulated.

Abstract: A laser light source (100) includes a semiconductor laser (101), a wavelength converting element (104) made of a non-linear optical crystal for converting excitation light from the semiconductor laser (101) into wavelength converted light having a wavelength different from the wavelength of the excitation light, a photodiode (109) for measuring a part of the wavelength converted light to be emitted from the wavelength converting element (104) as output light, a photodiode (110) for measuring the excitation light to be emitted from the wavelength converting element (104), and a control circuit (103), wherein the control circuit (103) simultaneously performs an output constant control of making the intensity of the wavelength converted light constant, using a current driving circuit (102), and a temperature control of adjusting the temperature of the wavelength converting element (104), using a heater (105).

Abstract: A display for illuminating a liquid crystal display panel with laser light of uniform light quantity distribution, and an illuminator for irradiating with laser light of uniform light quantity distribution are provided. The display includes a liquid crystal display panel 204, laser light sources 205, 206, 207 emitting laser light having wavelengths of green, red, and blue colors, a waveguide plate 201 arranged at the back side of the liquid crystal display panel 204 and performing multiple reflection of laser light, and a diffusion plate 202 arranged at the back side of the waveguide plate 201, diffusing laser light propagating in the waveguide plate 201 and emitting the light toward liquid crystal display panel 204.