Toyoda Gosei Co., Ltd.

Kabushiki Kaisha Toyota Chuo Kenkyusho

Denso Corporation

Toyota Jidosha Kabushiki Kaisha

Shizuoka University

Mirise Technologies Corporation

Tatsuya Yamashita

Manabu Kagami

Hiroshi Ito

Yukitoshi Inui

Akari Kawasaki

Kuniyoshi Kondo

Daisuke Inoue

Tadashi Ichikawa

Shin Sato

Kazuo Hasegawa

Akari Nakao

Masatoshi Yonemura

Kenji Yamada

Yasuhiko Takeda

Satoru Kato

Naomichi Okamoto

Makoto Nakai

Hisao Kato

Eiichi Okazaki

Naoya Take

Taku Suzuki

Masashige Sato

Masahiro Tomiki

An optical phase modulator includes a rib part extending in an extending direction. The rib part includes an N-type first rib portion and a P-type second rib portion arranged in a width direction to have a PN junction therebetween along the extending direction. An N-type first slab portion is connected to the first rib portion and a P-type second slab portion is connected to the second rib portion to provide a PN structure with the rib part in a cross-section having a normal direction along the extending direction. A P-type third slab portion is connected to the first rib portion and an N-type fourth slab portion is connected to the second rib portion to have a PNPN structure with the rib part in a cross-section having a normal direction along the extending direction. The PN structure and the PNPN structure are alternately disposed in the extending direction.

Optical phase modulator

A laser radar device includes: a light source; a projection light scanner that scans one part of light split off from emission light of the light source, and that generates transmission light for radiating onto a target object; an image forming section that forms plural respective reception lights of the transmission light reflected by respective locations of the target object into an image on a single flat plane as plural image-formation points; an optical receiver that is disposed at the plural image-formation points, and that includes plural unit optical reception sections for mixing each of the plural reception lights together with a reference light and performing optical heterodyne detection; and a reference light scanner that scans or distributes another light split off from the emission light from the light source, and that generates the reference light for radiating onto each of plural of the unit optical reception sections.

Laser radar, and light receiving method of laser radar

A microcomputer including first and second CPUs is provided. The first and second CPUs may execute identical control programs in parallel. The microcomputer may control a write access by the first or second CPU. The microcomputer may compare an output of the first CPU with an output of the second CPU. Data is written to a write target unit. The microcomputer outputs a write response signal to the first and second CPUs when a data write destination of the first and second CPUs is the write target unit. The microcomputer outputs an abnormality determination signal when data output from the first CPU mismatches with data output from the second CPU. The microcomputer writes the data to the write target unit when the data write destination of the first and second CPUs is the write target unit and the abnormality determination signal is not input.

Microcomputer

A diffraction structure includes a supporting layer, a high refractive index layer, and a low refractive index layer. The high refractive index layer has a first refractive index, is formed above the supporting layer, configures a waveguide guiding input light input from an input terminal along a specific direction, and includes an opening section formed along the specific direction. The low refractive index layer has a second refractive index lower that the first refractive index, and is formed so as to cover the high refractive index layer and fill the opening section. The opening section modifies the input light in at least one of direction or speed according to a wavelength of the input light, and outputs the modified light as output light.

Diffraction structure, diffraction grating, diffraction grating array, optical phased array, optical modulator, optical filter, laser source

A radar apparatus which can simply determine the sign of velocity of an object is provided. Laser light reflected by the object undergoes quadrature optical heterodyne detection performed by mixers, optical detectors, and a &#x3c0;/2 phase shifter, whereby I and Q component signals are output. A frequency analyzer performs FFT on a complex signal composed of the I component signal (real part) and the Q component signal (imaginary part) to thereby obtain its frequency spectrum. Since the frequency spectrum is calculated without being folded back even in a region where the frequency is negative, the sign of the Doppler frequency fd can be determined. When the Doppler frequency fd is positive, the sign of the velocity of the object is a direction toward the radar apparatus. When the Doppler frequency fd is negative, the sign of the velocity of the object is a direction away from the radar apparatus.

Radar apparatus and method of determining sign of velocity

A self-written branched optical waveguide is formed. A laser beamfrom a laser source (not shown) is focused with a lensonto the face of incidenceof an optical fiber. The laser beam of an LPmode was emitted from the face of emergence, and 'bimodal' light intensity peaks were arranged in the horizontal direction (.A). A slide glasscoated with a photocurable resin gelwas placed horizontally (.B). A single linear cured materialwas formed as the LP-mode laser beam was emitted from the face of emergenceof the optical fiber(.C). A branch portionwas then formed at a distance L from the face of emergenceof the optical fiber, which was followed by the growth of two cylindrical cured materialsand. The two cylindrical cured materialsandwere linear branches, and formed an angle of about four degrees. An optical waveguidethus formed was composed of cured materials, and(.D).

Optical waveguide and method for manufacturing the same

A transparent vessel is filled with a mixture solution containing a first photo-curable resin of a low refractive index and a second photo-curable resin of a high refractive index different in curing mechanism. When light at a wavelength capable of curing the first photo-curable resin but incapable of curing the second photo-curable resin is applied to the mixture solution through an optical fiber, the first photo-curable resin can be cured in a state in which the second photo-curable resin is enclosed in the cured first photo-curable resin. Because the refractive index increases according to curing, a self-condensing phenomenon can be generated so that an optical path portion is formed. The optical path portion emits leakage light to its surroundings to thereby form an outer circumferential portion. Then, all uncured resins in the mixture solution are cured. The outer circumferential portion containing a high percentage of the cured first photo-curable resin serves as a clad because the refractive index of the outer circumferential portion is lower than that of the optical path portion.

Material composition for producing optical waveguide and method for producing optical waveguide

In the condition that an acrylic transparent vessel is filled with a curable resin solution capable of being cured by a light, a plastic optical fiber is immersed in the curable resin solution. A laser beam is applied on the curable resin solution through the plastic optical fiber. The curable resin solution is cured gradually by the laser beam applied on the curable resin solution, so that an axial core is formed. Then, the transparent vessel is left at rest for predetermined time, or uncured part of the curable resin solution is removed from the transparent vessel and the transparent vessel is then filled with another curable resin solution. Then, ultraviolet rays are applied on the transparent vessel from the outside of the transparent vessel to cure the residual uncured part of the curable resin solution.

Optical waveguide and method for producing the same

Transparent parallel planar plates which are members for retaining an optical waveguide are provided erectly in an optical path of light in a transparent vessel in advance. An optical fiber is fixed into the transparent vessel while the optical fiber penetrates the transparent vessel, and an optical sensor is also disposed adjustably. Next, a first photo-curable resin solution is injected into the transparent vessel, and light with a predetermined wavelength for curing is emitted from the optical fiber so that the optical waveguide is self-formed by polymerization reaction. Because the parallel planar plates are transparent, the optical waveguide is formed so as to be extended again from the emission ports of the parallel planar plates. Finally, the optical waveguide is formed so as to reach a bottom surface of the transparent vessel. The optical waveguide has a structure in which the optical waveguide is firmly supported at four points in a forward end surface of the optical fiber, the parallel planar plates and the bottom surface of the transparent vessel. Accordingly, a firm optical waveguide device is formed.

Method of manufacturing optical waveguide device

Interference filters which are optical components are erected in advance on optical paths in a transparent container, and the transparent container is filled with a photo-curable resin solution. Further, a jig is prepared for manufacturing an optical waveguide device. The jig includes a housing, and holes. On this occasion, positions of the holes are set such that light input through the hole reaches the holes via the interference filters. Optical fibers are fitted into the holes of the housing and the housing is mounted on the transparent container. Next, light at a predetermined wavelength is guided into the optical fibers so that optical waveguides are formed in the photo-curable resin solution. Next, the photo-curable resin solution is exchanged for a low-refractive-index photo-curable resin solution and then the low-refractive-index photo-curable resin solution is solidified wholly by ultraviolet light. Finally, for example, an optical fiber, a light-receiving element, etc. are provided.

Optical waveguide device manufacturing jig, method of manufacturing optical waveguide device by use of the same jig, and the same optical waveguide device

Into a mixture solutionof a high-refractive-index photo-curable resin A and a low-refractive-index photo-curable resin B, light capable of curing only the resin A is led through an optical fiberso that a cured resinof the resin A having a diameter substantially equal to the diameter of a core portion of the optical fiber is formed so as to extend from a tip of the optical fiber. Then, the residual mixture solutionis cured. In this manner, a module having the previously cured high-refractive-index resinas an optical waveguide can be formed easily. On this occasion, the mixed state of the mixture solutioncan be kept good enough to facilitate the formation of the high-refractive-index resinwhen the solubility parameter &#x3b4;of the high-refractive-index photo-curable resin A and the solubility parameter &#x3b4;and volume fraction &#x3a6;of the low-refractive-index photo-curable resin B satisfy the following expression (4).|&#x3b4;&#x2212;&#x3b4;|&#x3c;&#x2212;7.5&#x3a6;+6.0&#x2003;&#x2003;(4)

Self-formable optical waveguide material composition

An optical fiber, a mixture solution of the photosetting resins polymerizing in two different polymerization types, and a transparent container are prepared. The photosetting resins are not copolymerized, and have different activation wavelengths of the photopolymerization initiators for hardening. Employing a combination in which the activation wavelength of a photopolymerization initiator for a photosetting resin with higher refractive index after hardening is longer than the activation wavelength of a photopolymerization initiator for a photosetting resin with lower refractive index after hardening, a core portion can be only formed by hardening the photosetting resin with higher refractive index due to a difference between two wavelengths. Thereafter, a clad portion can be formed by hardening two kinds of photosetting resins, whereby an optical transmission device can be manufactured.

A method of fabricating an optical waveguide structure includes the step of introducing light into a photo-curable liquid resin. The liquid resin can be a mixture of two types of photo-curable liquid resins having different curing initiation wavelengths and different refractive indexes. The method can include dipping one end of a fiber into the liquid mixture. Light having a wavelength &lgr; can be radiated from the tip end of the optical fiber in order to cure one of the photo-curable liquid resins thereby forming a waveguide. Light having a different wavelength &lgr; can be radiated from an area surrounding the waveguide so as to cure the liquid mixture and form a cladding portion around the waveguide.

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Nisshin, Japan

Tatsuya Yamashita