Fujitsu Corporation

Dainichiseika Color & Chemicals Mfg. Co., Ltd.

Trimatiz Limited

National Institute of Advanced Industrial Science and Technology

Sumitomo Osaka Cement Co., Ltd.

Hokkaido University

Noa Co., Ltd.

Hiroshi Nagaeda

Noriyasu Shiga

Nobuaki Mitamura

Norio Tanaka

Ichiro Ueno

Takashi Hiraga

Noritaka Yamamoto

Toshiko Mizokuro

Nobutaka Tanigaki

Yoichi Oikawa

Hirotomo Izumi

Kazuaki Akimoto

Norikazu Miyazaki

Kishio Yokouchi

Shigenori Aoki

Toshio Kataoka

Alexei L Glebov

Kaoru Higuma

Masahito Mure

Satoshi Kanai

Kaoru Sugimoto

Hideki Sudo

Takashi Ishiwada

Yuichiro Abe

Masahide Miyachi

Hiroyuki Sato

Yoshiaki Horiuchi

A scoliosis diagnosis assistance device includes: a first shape information acquisition module configured to acquire back shape information representing the three-dimensional shape of a back of a subject; a second shape information acquisition module configured to acquire minor-symmetry information representing a three-dimensional shape having a minor-symmetry relationship with the three-dimensional shape of the back of the subject with respect to a sagittal plane of the three-dimensional shape; a deviation distribution acquisition module configured to acquire a distribution of deviation between the three-dimensional shape represented by the back shape information and the three-dimensional shape represented by the mirror-symmetry information; and an output controller configured to cause a display to display the distribution of deviation, for example.

Scoliosis diagnosis assistance device, scoliosis diagnosis assistance method, and program

An optical deflection apparatus includes a signal light source configured to emit signal light having one or more wavelengths, a control light source configured to emit control light having a wavelength different from the wavelength of the signal light, a thermal lens forming optical element including a light absorption layer configured to transmit the signal light and selectively absorb the control light, and a beam-condensing unit configured to cause beam-condensation of the control light and the signal light at different convergence points in the light absorption layer. The thermal lens forming optical element causes convergence and divergence of the control light and the signal light on an incidence plane of the light absorption layer or its vicinity in a light traveling direction, wherein a thermal lens is reversibly formed in the light absorption layer due to a temperature increase occurring in a region where the control light is absorbed and its peripheral region, and the thermal lens changes a refractive index to change a traveling direction of the signal light.

Optical deflection method and optical deflection apparatus

The present invention relates to an optical receiver, and particularly, to an optical receiver by which a DQPSK-modulated optical signal is demodulated to a multilevel phase-modulated signal.

Optical receiver

A high-speed optical amplifier is considered to be an important optical device because of an increasing demand of routing, which is accompanied by an increase in complexity of networks. It is difficult to satisfy a response performance by related-art techniques, and there has been a problem in achieving a high-speed response performance of 10 microseconds or less. An optical amplifier according to the present invention includes: an input monitor means; an optical amplification meansincluding an optical amplification medium, and a control meansfor performing feed-forward control. When the optical amplification means is controlled by the feed-forward control in response to a signal of the input monitor means, an overshoot signal is applied as a control signal so that a slow response performance specific to the optical amplification medium has been improved, and thereby high-speed response performance has been achieved.

Optical amplifier

An optical device using an electro-optical element is of great utility value to industry, owing to its fast responsiveness and the like. Prior art has problems such as high cost due to a large number of parts, large device size, and high drive voltage, and it has been a challenge to reduce the number of parts to be used, to downsize the device, and to reduce drive voltage. An optical device of the invention has a reflection structure comprising an input fiberand an output fiberwhich are fastened by a duplex ferrule, a collimating lens, and a reflector elementfor reflecting light. The optical device further comprises a cylindrical lens functioning as a condenser lens, and an electro-optical element, which is placed near a collection point of the condenser lens. Electrodes of the electro-optical elementare configured such that the interelectrode distance becomes smaller the closer they are to the collection part.

Optical device using variable polarization element

A flip-flop circuit of the present invention includes a first switch and a second switch which are connected in series to each other. The first switch includes: two input ports upon which light source light and signal light are incident; two output ports for outputting an optical output; and a thermal lens forming element for forming a thermal lens in a predetermined optical inputting condition. Although the second switch is composed in the same manner as that of the first switch, a relation between the wave-lengths to be utilized is inverted. When a state is changed from OFF to ON, a pulse signal is inputted for setting and one of the rays of output light of the second switch is fed-back to the first switch so as to maintain the state of ON. When the state is changed from ON to OFF, a pulse of additional signal light is inputted. Due to the foregoing, the two states of ON and OFF can be stably maintained.

Optical flip-flop circuit

A spectroscopic apparatus which is compact in size and performs high-precision light-splitting with a large angular dispersion. An optical input-processing section outputs a filtered transmitted light, using a bandpass filter that transmits only wavelength bands at one period of an input light, and collects the filtered transmitted light to generate a collected beam. An optic includes a first reflection surface and a second reflection surface which are high but asymmetric in reflectivity, and causes the collected beam incident thereon to undergo multiple reflections within an inner region between the first reflection surface and the second reflection surface, to thereby cause split beams to be emitted via the second reflection surface. A received light-processing section performs received light processing of the beams emitted from the optic. A control section variably controls at least one of a filter characteristic of the bandpass filter and an optical length through the optic.

Spectroscopic apparatus

The optical deflector includes the electro-optical element to deflect light by utilizing its refractive index variation, and it also includes a reflective adjustable optical deflector element with a reflective element to reflect the deflected light. This arrangement provides down-sized optical devices, such as variable optical attenuators, optical shutters, and optical switches, with high response speed and low insertion loss.

Reflective adjustable optical deflector and optical device employing the same

The intensity of signals in optical networks can be controlled using a variable optical attenuator (VOA). The present invention is a VOA that is particularly well suited for optical networks, for example to provide channel-by-channel normalization of gain control of wavelength division multiplexed signals. The inventive VOA includes a waveguide having a cladding that includes an electro-optical material and electrodes that produce an electric field within the electro-optical material when a voltage difference is applied to the electrodes. The VOA also includes a layer that is parallel to the core of the waveguide and that optically couples to the core to receive light from the attenuated signal. A power meter receives light from the layer as an indication of the amount of light attenuated from the signal and for controlling the voltage to the electrodes.

Variable optical attenuator having a waveguide and an optically coupled layer with a power monitor

An optical device includes a small and low-cost variable polarization plane rotator that can control a rotation angle of the polarization plane easily. A variable polarization plane rotator is provided with a &#x3bb;/4 phase plate having an optical axis in the same direction as, or at a 90 degree angle relative to, a polarization direction of an input light beam. A phase difference variable element has an optical axis at a &#xb1;45 degree angle relative to the optical axis of the &#x3bb;/4 phase plate, to apply a variable phase difference between the polarization components parallel to and perpendicular to the optical axis thereof. A phase difference adjustment section adjusts the variable phase difference of the phase difference variable element, wherein the input light beam after being transmitted through the phase difference variable element to form elliptically polarized light or circularly polarized light, is transmitted through the &#x3bb;/4 phase plate to form linearly polarized light. The polarization plane of the input light beam is rotated by an angle corresponding to the phase difference applied by the phase difference variable element.

Variable polarization plane rotator and optical device using same

A Faraday rotator which is improved in temperature-dependent Faraday rotation angle characteristic and thus in quality. Faraday rotation is caused by a first magnetic field applied to a magneto-optical crystal of the Faraday rotator, and the Faraday rotation angle is controlled by a second magnetic field over an entire variable strength range of the second magnetic field. The magneto-optical crystal is positioned in such a manner that the direction of a combined magnetic field of the first and second magnetic fields, except for the direction of the first magnetic field, is variable intermediately between easy and hard magnetization axes of the magneto-optical crystal.

Faraday rotator

The present invention aims at providing a transmission wavelength characteristics variable optical element which can actively equalize changes of the wavelength characteristics due to temperature changes, and providing a wavelength characteristics variable apparatus, an optical amplifier, an optical transmission system, and a control method of the transmission wavelength characteristics, which use such an optical element. To this end, the transmission wavelength characteristics variable optical element according to the present invention comprises: an light interference section in which for example reflection films are formed on a light incident plane and a light emitting plane of a magneto-optic crystal; a permanent magnet that applies a fixed magnetic field to the magneto-optic crystal; an electromagnet that applies a variable magnetic field in a direction different from that of the fixed magnetic field; and a variable current source that controls the current flowing in the electromagnet, and varies transmission wavelength characteristics which occur due to an interference of light multireflected between the reflection films, by changing a Faraday rotation angle given to the light being propagated within the magneto-optic crystal, corresponding to a synthetic magnetic field formed by the fixed magnetic field and the variable magnetic field.

TRANSMISSION WAVELENGTH CHARACTERISTICS VARIABLE OPTICAL ELEMENT, AND WAVELENGTH CHARACTERISTICS VARIABLE APPARATUS, OPTICAL AMPLIFIER, OPTICAL TRANSMISSION SYSTEM, AND CONTROL METHOD OF TRANSMISSION WAVELENGTH CHARACTERISTICS, USING SAME

An airgap type etalon has a higher degree of design freedom of a wavelength-temperature characteristic so that such a wavelength-temperature characteristic can be freely adjusted. The airgap type etalon includes a fixing block having one flat surface, and a transparent parallel flat plate having parallel flat surfaces formed with an antireflection coating and a reflection augmenting coating thereon, respectively. The flat surface at the antireflection coating side is joined to the flat surface of the fixing block. A parallel flat spacer has a thickness greater than that of the transparent parallel flat plate and an expansion coefficient different from that of the transparent parallel flat plate. One of the flat surfaces of the parallel flat spacer is joined to the flat surface of the fixing block. A transparent flat plate has opposite flat surfaces formed with an antireflection coating and a reflection augmenting coating thereon, respectively. The flat surface at the reflection augmenting coating side is joined to the other of the flat surfaces of the parallel flat spacer, wherein a Fabry-Perot interferometer is formed based on an airgap positioned between the flat surface of the transparent parallel flat plate and the flat surface of the transparent flat plate, which flat surfaces face each other.

Airgap type etalon and apparatus utilizing the same

An optical device includes a small and low-cost variable polarization plane rotator that can control a rotation angle of the polarization plane easily. A variable polarization plane rotator is provided with a &lgr;/4 phase plate having an optical axis in the same direction as, or at a 90 degree angle relative to, a polarization direction of an input light beam. A phase difference variable element has an optical axis at a &plusmn;45 degree angle relative to the optical axis of the &lgr;/4 phase plate, to apply a variable phase difference between the polarization components parallel to and perpendicular to the optical axis thereof. A phase difference adjustment section adjusts the variable phase difference of the phase difference variable element, wherein the input light beam after being transmitted through the phase difference variable element to form elliptically polarized light or circularly polarized light, is transmitted through the &lgr;/4 phase plate to form linearly polarized light. The polarization plane of the input light beam is rotated by an angle corresponding to the phase difference applied by the phase difference variable element.

Growing community of inventors

Sapporo, Japan

Hiroshi Nagaeda