Abstract: An optical waveguide device has a substrate composed of a nonlinear optical material and a periodically domain-inverted structure having the same composition as the nonlinear optical material, where the domain-inverted structure has a refractive index distribution relying on the domain-inverted structure.

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: It is easy to increase output with a wide stripe laser, but the lateral mode is a multimode, and the coupling efficiency is low with a single-mode fiber or a single-mode waveguide, creating problems in terms of application to devices of high coherence. In view of this, the light emitted from a wide stripe semiconductor laser is passed through a mode converter and a wavelength selecting filter, then fed back to the active layer of the semiconductor laser, which fixes the oscillation mode of the semiconductor laser to single mode.

Abstract: A method for forming a domain-inverted structure includes the following: using a ferroelectric substrate (1) having a principal surface substantially perpendicular to the Z axis of crystals; providing a first electrode (3) on the principal surface of the ferroelectric substrate, the first electrode having a pattern of a plurality of electrode fingers (5) that are arranged periodically; providing a counter electrode (6) on the other side of the ferroelectric substrate so as to be opposite from the first electrode; and applying an electric field to the ferroelectric substrate with the first electrode and the counter electrode, thereby forming domain-inverted regions corresponding to the pattern of the first electrode in the ferroelectric substrate. Each of the electrode fingers of the first electrode is located so that a direction from a base to a tip (5a) of the electrode finger is aligned with the Y-axis direction of the crystals of the ferroelectric substrate.

Abstract: A video projector of the present invention includes a laser projection unit (50) that has linear polarization short wavelength laser light sources (1)˜(3) and emits laser lights from the laser light sources, a lens system (6a) that collects the laser lights from the laser projection unit (50), a liquid crystal cell (7) that spatially modulates the collected laser lights, a camera shake correcting optical system (110) that is capable of translating vertically and horizontally on a plane that is perpendicular to the optical axis of the laser projection unit (50), a prism (24) that transmits the laser lights from the liquid crystal cell (7) and branches the light reflected by the screen (10), and a camera device (60) that can observe or capture the video image that is branched by the prism (24). The present invention provides a video projector that can prevent the camera shake and can be held in hands.

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: An electric switch includes a ferroelectric substrate to which metal is added, a pair of electrodes provided on the ferroelectric substrate, and an electric field applying portion for changing the direction of polarization in part of the ferroelectric substrate.

Abstract: A light diffuser containing light diffusing elements is arranged in the most appropriate position between a spatial light modulator and an illumination optical system. Thereby, particles as light diffusing elements diffuse rays of light emitted from a laser light source. Accordingly, indefinite numbers of speckle pattern are formed so that, for example, a speckle noise which occurs on an image projected to a screen is reduced. As a result, loss of light amount after light diffusion is suppressed to small amount, and thereby a laser image display apparatus capable of displaying a bright and high-quality image having no luminosity irregularity is provided.

Abstract: It is easy to increase output with a wide stripe laser, but the lateral mode is a multimode, and the coupling efficiency is low with a single-mode fiber or a single-mode waveguide, creating problems in terms of increasing output. To solve these problems, the light emitted from a wide stripe semiconductor laser is passed through a mode converter and a wavelength selecting filter, then fed back to the active layer of the semiconductor laser, which fixes the oscillation mode of the semiconductor laser to single mode.

Abstract: An optical waveguide device includes a waveguide layer that converts a wavelength of incident light and emits converted light. In the waveguide layer, a ridge waveguide and slab waveguides are provided, the slab waveguides being formed on both sides of the ridge waveguide with recess portions intervening therebetween. The waveguide layer satisfies a multi-mode condition for the incident light, and light propagating through the ridge waveguide is in a single mode.

Abstract: An optical pickup and an optical information recording/reproducing device are provided, each of which is capable of forming a super-resolution spot to conduct micro-mark recording, and does not undergo signal degradation due to an increased sidelobe in a reproducing operation. A variable phase filter having three regions to produce a phase difference in a radial direction is used, to provide a phase difference of ? between the center region and the side regions in a recording operation, so that a super-resolution spot is formed on a recording layer of the optical disk. In a reproducing operation, a phase difference is nullified between the regions of the variable phase filter, so that a normal light spot at a diffraction limit having a smaller sidelobe is formed. The variable phase filter can be formed with a homogeneous-alignment liquid crystal element.

Abstract: The present invention relates to a method for laminating substrates, including the steps of locating a surface of a first substrate and a surface of a second substrate at positions close to each other or partially bringing them in contact with each other; supplying a volatile liquid between the surface of said first substrate and the surface of said second substrate; and evaporating said volatile liquid so as to laminate the substrates with each other.

Abstract: A 2-D beam scan method using a galvanometer mirror and a polygon scanner has a problem that the polygon scanner is large and noises are increased. Also, a method of oscillating a compact mirror has a problem that a brightness distribution is produced depending on a scan angle. Hence, a beam is scanned while a relatively small mirror, such as an MEMS mirror, is oscillated at or in the vicinity of the resonance frequency. In this instance, the scan angle is corrected with the use of a correction optical system for uniform illumination to be achieved.

Abstract: An optical information processing device is provided with a multi-wavelength light source that emits light of two or more different wavelengths, a filter portion that separates the light emitted from the multi-wavelength light source according to wavelength, and a condensing lens that focuses a plurality of lights separated by the filter portion on the same point for multi-wavelength recording.

Abstract: An optical waveguide device has a substrate composed of a nonlinear optical material and a periodically domain-inverted structure having the same composition as the nonlinear optical material, where the domain-inverted structure has a refractive index distribution relying on the domain-inverted structure.

Abstract: A light generating apparatus includes: a submount; a semiconductor laser chip mounted on the submount; a substrate which is mounted on the submount and includes an optical waveguide; and a substance having a predetermined thickness which is disposed between the semiconductor laser chip and the substrate. In an oscillation wavelength stabilizing apparatus for a light source, the light source is a semiconductor laser which includes: an active region for providing gain; and a distributed Bragg reflection (DBR) region for controlling an oscillation wavelength.

Abstract: A two-dimensional image formation apparatus according to the present invention is provided with laser sources (1a)˜(1c), diffusers (6a)˜(6c) for diffusing light, illumination optical systems for irradiating the diffusers (6a)˜(6c) with lights emitted from the laser sources (1a)˜(1c), diffuser vibration units (13a)˜(13c) for vibrating the diffusers (6a)˜(6c), and spatial light modulators (7a)˜(7c) disposed near the diffusers (6a)˜(6c), for modulating the lights emitted from the laser sources (1a)˜(1c) and diffused by the diffusers (6a)˜(6c), wherein the diffusers (6a)˜(6c) are vibrated by the diffuser vibration units (13a)˜(13c) at a velocity that satisfies a relationship, V>d×30 (millimeters/sec), which is established between the grain size d of the diffusers and the vibration speed V of the diffusers, whereby speckle noise existing in an image projected on a screen (11) can be effectively reduced.

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: When a wavelength of a first laser beam with which a first recording medium including a first recording layer is recorded and reproduced is indicated as ?1 (nm), a wavelength of a second laser beam with which a second recording medium including a second recording layer is recorded and reproduced as ?2 (nm), the relationship between the wavelength ?1 and the wavelength ?2 is set to be expressed by 10?|?1??2|?120. The first recording layer has a light absorptance ratio of at least 1.0 with respect to the wavelength ?1. The light transmittance of the first recording medium with respect to the wavelength ?2 is set to be at least 30 in both the cases where the recording layer is in a crystal state and in an amorphous state. In order to record and reproduce the optical multilayer disk with the above-mentioned characteristics, a multiwavelength light source with the following configuration is used.

Abstract: The present invention provides a reflection-type laser projector (100) which projects modulated laser beams outputted from a laser projection unit (40), on a screen, wherein a reflector (112) as a constituent of the screen (110) has reflection characteristics of reflecting, among the incident light, only laser beams of three colors of red, blue, and green, which are projected from the laser projection unit (40) and light in the neighboring wavelength band, and transmitting light in other wavelength band, thereby preventing pictures on the screen (110) from becoming hard to be seen due to effects of indoor illumination or light from outdoors.