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.

Abstract: There is provided a light source device which can miniaturize a two-dimensional image display device as small as possible. The light source device is provided with three coherent light sources (11a), (11b), and (11c) corresponding to red, blue, and green; prisms (12a) and (12c) for reflecting lights emitted from the coherent light sources (11a) and (11c); and a diffraction part (20) comprising a single volume hologram on which plural gratings are multiply-formed, which gratings diffract the light emitted from the coherent light source (11b), and the lights that are emitted from the coherent light sources (11a) and (11c) and reflected by the prisms (12a) and (12b) so that these lights propagate in the same optical path.

Abstract: A laser emission device which can emit a high-luminance and high-monochromaticity light with a high efficiency, a low power consumption, and a long lifetime, and a image display device using the laser emission device are provided.

Abstract: A surface emitting laser includes an active layer disposed on a semiconductor substrate, and a pair of upper and lower electrodes for injecting carriers into the active layer. The plane surface of the lower electrode is shaped into a star so that injection of current into the active layer from the lower electrode is carried out with a high density at the center of the lower electrode and with a low density at its periphery part. In the surface emitting laser, the density distribution of the carriers injected into the active layer corresponds to the power distribution of light inside the active layer. Thereby, hole burning due to an increase in the current density in the region of the active layer corresponding to the peripheral part of the electrode is avoided, and the transverse mode stability during high output operation is significantly enhanced to improve high-output characteristic.

Abstract: A laser image display device includes: a first laser light source capable of outputting a laser light having a first wavelength; a second laser light source capable of outputting a laser light having a second wavelength; and a color output conversion controller capable of individually controlling power of the first and the second laser light source displaying the pixels constituting an image according to an input signal.

Abstract: The light sources (10) according to the present invention includes a laser oscillator including a semiconductor laser (11), a drive circuit (18) for the semiconductor laser (11), an ACC circuit (13), an APC circuit (14), and a switch (SW) (15), and a starting drive current storage device (16), and is controlled in such a manner that the driving current at the start of the laser driving be always constant, and the after the start of the lighting, it is switched to the APC operation to carry out the power control of the laser light output.

Abstract: A laser light source includes a fundamental laser generator that generates a fundamental laser light, a wavelength conversion element that is made of a ferroelectric crystal with a periodically poled structure and converts the fundamental laser light to a laser light having a different wavelength, a holding member that holds at least a part of an element surface of the wavelength conversion element that crosses a polarization direction of the periodically poled structure, and an insulation layer that is provided between the holding member and the element surface. Electric resistivity of the insulation layer is 1×108 ?·cm or higher.

Abstract: Disclosed herein is a laser projection device which can keep the colors of red, blue, and green laser beams constant even in high ambient temperature. The laser projection device includes a red laser light source which emits a red laser beam, a temperature sensor for detecting the temperature of the red laser light source, and a radiating unit for radiating heat from the red laser light source to the outside based on the temperature of the red laser light source detected by the temperature sensor.

Abstract: In a display unit which makes coherent light perform scanning on a screen to display an image, it is necessary to rotate a polygon mirror at ultrahigh speed for display of a high resolution image such as HDTV, and therefore, a high-performance polygon mirror must be employed, and further, noise and power consumption during rotation of the polygon mirror cause problems. Mirrors for multiple reflection (6a) and (6b) are inserted in a coherent light scanning optical system, whereby plural scanning lines can be obtained while one plane of the polygon mirror (5) scans one line of coherent light, leading to reduction in the rpm of the polygon mirror.

Abstract: A wavelength conversion optical device is provided with a fundamental wave light source (301) which outputs a fundamental wave (L11) including a P polarized light and an S polarized light that are perpendicular to each other, and two wavelength conversion mechanisms (303a, 303b) each having a polarization inversion formation part which wavelength-converts the fundamental wave (L11) to generate harmonic waves, and the first-stage wavelength conversion mechanism (303a) performs wavelength conversion of the P polarized light of the fundamental wave (L11) while the second-stage wavelength conversion mechanism (303b) performs wavelength conversion of the S polarized light of the fundamental wave (L11), whereby absorption of a second harmonic wave (green light) due to a third harmonic wave (ultraviolet light) is reduced, and stability and reliability of the wavelength-converted light output are enhanced, thereby providing a wavelength conversion optical device which can output a wavelength-converted light capable o

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: 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: An optical element (10) according to the present invention is provided with a plurality of waveguides (11)˜(13) and a plurality of light path coupling parts (21), (22) coupling adjacent waveguides so as to optically couple said plural waveguides serially, wherein the paths for transmitting lights through the plural waveguides are curved at the optical path coupling parts, thereby the optical elements which is converted the incident laser light into the emitted light having uniform cross-sectional light intensity distribution can give a compact structure, further a laser light source that employs the optical element, and a two-dimensional image forming apparatus that employs the laser light source can also give a compact structure.

Abstract: Efficient coupling structures are important for the realization of reliable and economical integrated optical circuit applications. This paper presents a new approach for the simulation of an anisotropic plasma etching process in silicon based on a string point model as well as the realization and the results of etching processes in silicon, silicon dioxide, silicon oxinitride and silicon nitride which are fundamental for the fabrication of coupling structures. The connections to active and passive components were fabricated using plasma etching and deposition processes which are compatible with C-MOS or BIC-MOS technology. The realized waveguide-detector structures with vertical and horizontal silicon PIN-diodes exhibit efficiencies close to 90% for wavelength below 1.1 micrometers. The diodes can detect signals of modulation frequencies of more than 400 MHz due to horizontal light injection and capacitances less than 1 pF.

Abstract: An object of the invention is to increase the beam diameter of a laser beam, and perform high-output wavelength conversion without causing crystal damage. A laser wavelength conversion device includes a laser wavelength conversion element for allowing incidence of a laser beam as a fundamental wave to convert a part of the fundamental wave laser beam into a wavelength-converted laser beam having a wavelength different from a wavelength of the fundamental wave laser beam. The laser wavelength conversion element includes a non-linear optical crystal having periodically polarization reversed portions. The polarization reversed portions are formed in such a manner that a region where a wavelength conversion efficiency is substantially uniform extends in a polarization direction of the non-linear optical crystal. The incident laser beam is converted into the wavelength-converted laser beam with the wavelength conversion efficiency.

Abstract: In a laser picture formation device which forms a vide image by irradiating lights emitted from plural laser light sources (1a, 1b, 1c) which obtains monochromatic lights from laser lights which are outputted from the respective laser light emission parts to spatial light modulators (5a, 5b, 5c), each of the plural laser light sources (1a, 1b, 1c) detect the output of laser light which is emitted from the respective laser light emission parts on the basis of the modulation input signal which for modulating the spatial light modulator. Thereby, it is possible to confirm the deterioration situation of the respective laser light emission parts without deteriorating the video images which are projected onto the screen, as well as without separating the synthesized light respectively.

Abstract: There is provided a stable optical element having a fine, uniform, and wide-ranging domain inversion structure in a ferroelectric crystal. This includes a plurality of domain inversions (101) formed on an MgO:LiNbO3 substrate (100), and a groove (102) formed on the substrate surface between the domain inversions (101). The depth T? of substantially all of the domain inversions (101) satisfies the relation T?<T with respect to the substrate thickness T.

Abstract: A surface emitting laser (100a) includes an active layer (3) disposed on a semiconductor substrate (2a), and a pair of upper and lower electrodes (5,6) for injecting carriers into the active layer (3). The plane surface of the lower electrode (6) is shaped into a star so that injection of current into the active layer (3) from the lower electrode (6) is carried out with a high density at the center of the lower electrode (6) and with a low density at its periphery part. In the surface emitting laser (100a), the density distribution of the carriers injected into the active layer corresponds to the power distribution of light inside the active layer. Thereby, hole burning due to an increase in the current density in the region of the active layer corresponding to the peripheral part of the electrode is avoided, and the transverse mode stability during high output operation is significantly enhanced to improve high-output characteristic.

Abstract: In a short-wavelength laser module, long-term reliability is lost because of unnecessary gas deposited on the end face of its optical waveguide. A short-wavelength laser module has a package structure wherein a package lid used when the short-wavelength laser module is hermetically sealed does not make contact with internal gas, and a process of accelerating the polymerization of a securing agent used inside the package is incorporated, whereby unnecessary gas from the securing agent is eliminated and the long-term reliability of the output is attained.

Abstract: There is provided a light source device which can miniaturize a two-dimensional image display device as small as possible. The light source device is provided with three coherent light sources (11a), (11b), and (11c) corresponding to red, blue, and green; prisms (12a) and (12c) for reflecting lights emitted from the coherent light sources (11a) and (11c); and a diffraction part (20) comprising a single volume hologram on which plural gratings are multiply-formed, which gratings diffract the light emitted from the coherent light source (11b), and the lights that are emitted from the coherent light sources (11a) and (11c) and reflected by the prisms (12a) and (12b) so that these lights propagate in the same optical path.