Abstract: The laser picture formation device includes a two-dimensional modulation element performing video image modulation as well as four or more laser light sources having different center wavelengths. The video images which have no speckle noises at the wavelength region that has high visibility, which are realized by simultaneously emitting the laser lights of green (G) and yellowish green (Y) which have particularly high visibility, and video images which are vivid as cannot be represented by the conventional display, and which can be realized by controlling the laser lights of respective colors independently, can be displayed. Particularly, by modulating the two-dimensional modulation element and the laser light output with synchronized with each other, various video displays are enabled.

Abstract: After forming domain inverted layers 3 in an LiTaO3 substrate 1, an optical waveguide is formed. By performing low-temperature annealing for the optical wavelength conversion element thus formed, a stable proton exchange layer 8 is formed, where an increase in refractive index generated during high-temperature annealing is lowered, thereby providing a stable optical wavelength conversion element. Thus, the phase-matched wavelength becomes constant, and variation in harmonic wave output is eliminated. Consequently, with respect to an optical wavelength conversion element utilizing a non-linear optical effect, a highly reliable element is provided.

Abstract: A wavelength separator is provided with a reflective color filter arranged to intersect with an optical path of light emerging from a principal surface of a light guide plate, and a recycle portion arranged at a side of the light guide plate opposite to the reflective color filter. Out of light incident on the light guide plate, light reflected by the reflective color filter is returned to the reflected color filter again by being reflected by the recycle portion via the light guide plate.

Abstract: A planar illumination device includes a laser light source; a light guide plate for guiding light entered through an end surface to be outputted from a first principal surface; an optical element which forms diffusing light outputted from the laser light source into a substantially parallel light in a thickness-wise direction of the light guide plate and which outputs the resulting parallel light to the end surface of the light guide plate; and a first light deflecting unit for deflecting a propagation direction in the light guide plate of the light incident thereon, wherein the first light deflecting unit is arranged such that a degree of deflection of the light incident on the light guide plate differs according to positions in the light guide plate, to make an amount of light outputted from the first principal surface uniform in the first principal surface.

Abstract: A two-dimensional image display device having a center wavelength of a red color source set in a range from 635 nm to 655 nm and having a center wavelength of a blue light source set in a range from 420 nm to 455 nm, to obtain a bright and clear image at minimum power consumption.

Abstract: A laser light source (10) has semiconductor lasers (1) and a waveguide tube (3) for propagating emission light from each of the semiconductor lasers (1). The semiconductor lasers are arranged on the upper end on the incident surface (31) side of the waveguide tube such that the emission light (4) from each of the semiconductor lasers enters into the waveguide tube from one end surface (31) of the waveguide tube and exits from the other end surface (32) of the waveguide tube. The structure can realize a small-sized laser light source having high output and capable of outputting emission light having uniform emission light intensity distribution.

Abstract: A fiber laser includes: a solid laser fiber doped with a rare earth element; a first grating fiber provided at one end portion of both ends along an optical axis direction of the solid laser fiber; and a first reflective element provided at the other end portion of the solid laser fiber. The first and second reflective elements constitute a resonator structure for the solid laser fiber; the first grating fiber Bragg-reflects only two polarizations of a first polarization having a first wavelength, and a second polarization having a second wavelength different from the first wavelength and being mutually orthogonal with the first polarization in a polarization direction; and at least one reflection wavelength of light which is reflected at the first reflective element and either one wavelength of the two polarizations which are Bragg-reflected at the first grating fiber coincide with each other.

Abstract: There has been a problem that pumping light leaks from a part having a coating at the joint of a double-clad fiber added with a rare earth and a general single-mode fiber, and heat is generated partly from the fiber by this energy thus causing deterioration of the fiber. Deterioration of a fiber due to residual excitation light can be prevented by preventing residual excitation light in a double-clad fiber from exiting to a single-mode fiber, and the reliability is enhanced. Output of oscillation light can be increased because output of excitation light is not limited. Furthermore, a laser display having a high color reproducibility can be achieved by employing a light source combining a fiber laser light source and a wavelength conversion module.

Abstract: In a coherent light source in which limitations on the wavelength of emitted light are relaxed, a coherent light source for simultaneously emitting a first light (3) and a second light (4) having a wavelength shorter than that of the first light (3), includes: a light source main body emitting at least the first light (3); a mirror (5) which transmits or reflects the first light (3); and a functional film (6) provided on at least a part of the mirror (5). The functional film (6) has a photocatalytic effect to be induced by the second light (4).

Abstract: An optical element is provided that includes a base substrate, a waveguide substrate, and a thin film layer that is provided between the base substrate and the waveguide substrate and that has a single-layer structure of a multilayer structure including a film containing Ta2O5 or Nb2O5 as a principal component.

Abstract: A wavelength conversion laser light source includes: an element temperature switching section that switches a temperature of the wavelength conversion element according to a harmonic wave output value as set in an output setting device, and the element temperature switching section for switching a temperature of a wavelength conversion element according to a harmonic wave output level as set in the output setting device, wherein the element temperature switch section includes an element temperature holding section that holds the wavelength conversion element at the temperature as switched by the element temperature switching section.

Abstract: There has been a problem that interference noise called speckle noise occurs in a two-dimensional image display device using laser, and there is no applicable green light source although the speckle noise can be reduced by using a multi-wavelength light source. The present invention adopts a Yb-doped clad pump fiber (103) which is a rare-earth-doped fiber as a laser activation substance, whereby a peak of a fluorescence spectrum can be significantly increased as compared with a case of using an oxide crystal, and a variation width of an oscillation wavelength can be increased. Further, since the rare-earth-doped fiber is used as a fiber amplifier without providing laser mirrors at both ends thereof, control for a resonator length, which has been required in a conventional device (wherein an oxide crystal is used as a laser medium), is dispensed with, and thereby high-speed wavelength control is achieved, resulting in reduction in speckle noise when it is mounted on a two-dimensional image display device.

Abstract: A laser light source 1 outputs a laser. A condenser lens 80 condenses the laser outputted from the laser light source 1, and outputs it to an optical fiber 8. The laser that propagates through the optical fiber 8 enters a light guide panel 2. The light guide panel 2 converts the inputted laser into a planar illumination light. The planar illumination light passes through a light passing control section 4 and illuminates a liquid crystal panel 7, which is a spatial modulation element that convert light into an image. The light passing control section 4 controls a scatter pattern during the passing of the laser individually in each predefined image area, by a control circuit 81. Consequently, an image area 5 in which a speckle noise is reduced and an image area 6 in which the speckle noise is generated, are formed on a liquid crystal panel 7.

Abstract: An image display apparatus includes a laser source for emitting ultraviolet or blue display-use laser light having a wavelength of 420 nm or less; and a display unit including a fluorescent light generating section for generating fluorescent light when irradiated with the display-use laser light, wherein the display unit displays an image using the fluorescent light generated by the fluorescent light generating section, wherein the display unit further includes an extraneous light shielding section for shielding an extraneous light which is emitted from a back side of the display unit and which has a wavelength in a range where the fluorescent light is generated so as to prevent the extraneous light from entering in the fluorescent light generating section.

Abstract: The present invention aims to provide a wavelength converter capable of stably obtaining a W-class high-output green laser beam and a 2D image display device using this wavelength converter. By causing a polarization direction of a laser light source for generating an excitation light and that of a light emitted from an oscillator to orthogonally intersect, the deterioration of an excitation light source by an ASE is suppressed by a polarization splitting element provided between a laser resonator and the laser light source.

Abstract: A control apparatus for a hybrid vehicle includes: a drive mode determination device that determines one drive mode from a plurality of drive modes based on a status of the vehicle, wherein the drive modes include: an engine stop motor drive mode in which the vehicle is driven by a driving force from a motor while stopping an engine; an idle cylinder deactivation motor drive mode in which the vehicle is driven by the driving force from the motor by operating a power generator as an electric motor by running the engine while maintaining the engine deactivated; and an engine drive mode in which the vehicle is driven by a driving force from the engine; and a transition rate modification device that, when it is determined by the drive mode determination device that a mode transition from a current drive mode to another drive mode should take place, modifies a transition rate for transitioning from the current drive mode to the another drive mode according to the drive mode to be transitioned.

Abstract: Red light emitted from a red laser light source, green light emitted from a green laser light source and blue light emitted from a blue laser light source are incident on a first disc body of a color wheel, are transmitted or reflected in conformity with the colors of the lights in wavelength selecting regions of a second disc body every time the color wheel performs a predetermined rotation. AS being reflected by the first disc body, the lights are divided into different positions to be emitted from the color wheel and irradiated to irradiation regions successively switched by an upward or downward reciprocal movement of a mirror group.

Abstract: For performing hologram recording or reproduction, an oscillation wavelength half value width ?? of a coherent light source 21 satisfies a relationship of ??<?2/(S×2 sin ?), when 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 21 can suppress generation of an unnecessary interference fringe due to the stray light, and stably record and reproduce holograms.

Abstract: A light source portion having laser light sources emitting red light, green light, and blue light and conventionally disposed integrally with the liquid crystal display panel is spatially separated from the liquid crystal display panel. Accordingly, the power supply, the optical system, and the heat source are incorporated into the light source portion and are thereby completely separated from the liquid crystal display panel. A laser beam emitted from the light source portion is guided to the liquid crystal display panel via a fiber. In this manner, it is possible to achieve a liquid crystal display device capable of significantly reducing the liquid crystal display panel in thickness and weight.

Abstract: A laser light source is provided with a pump light source (1) comprising a semiconductor laser, a solid laser medium (2) which is excited by the semiconductor laser, and multi-mode means for changing at least either a longitudinal mode or a transverse mode of laser oscillation of the solid laser. The oscillation light of the laser medium excited by the light outputted from the pump light source is changed by the multi-mode means into output light (5) having a plurality of oscillation spectra and is outputted, thereby a small, high power, and highly efficient low coherent light source can be realized, and a laser light source having reduced speckle noises can be provided.