The Furukawa Electric Co., Ltd.

Omron Corporation

Canon Kabushiki Kaisha

Totoku Electric Co., Ltd

Takeshi Takagi

Yoshihiro Emori

Hiroshi Matsuura

Yu Mimura

Koji Kajiwara

Kazuyou Mizuno

Kousuke Kashiwagi

Mieko Yamagaki

Kazuaki Hyuga

Satoru Abe

Fumio Koyama

Miho Kaiga

Kenichi Iga

Kazuhiro Ikeda

Tatsuya Hatano

Atsushi Koyama

Sugio Wako

Xiongfei Zhang

An optical fiber laser device generates laser light by using an optical amplifying fiber as an amplification medium in a laser oscillator and includes: an optical outputting fiber configured to emit laser light to an outside; a return-light-attenuating portion configured to perform an attenuation process to return light propagating through at least the optical outputting fiber in a reverse direction of the laser light; a thermal conversion unit provided at the return-light-attenuating portion and configured to convert the return light into heat; a temperature-monitoring device configured to measure an increase in a temperature, of the return-light-attenuating portion, caused by the heat converted by the thermal conversion unit; and a control unit configured to decrease or stop an output of the laser light when the temperature measured by the temperature-monitoring device becomes a predetermined threshold temperature or higher.

Optical fiber laser device

A spatial coupling provided between an amplified-light waveguide and an output-light waveguide includes a wavelength selecting element that selectively transmits a light having a desired wavelength band out of a spontaneous emission light generated in the amplified-light waveguide and a lens unit that couples the spontaneous emission light to the wavelength selecting unit. An input-side light reflecting unit provided between a semiconductor pumping laser and the amplified-light waveguide and an output-side light reflecting unit formed on an output side of the spatial coupling unit form a laser resonator.

Light source

The invention provides a Stokes parameter measurement device and Stokes parameter measurement method that enable high-precision measurement. The Stokes parameter measurement device comprises a polarization splitting device which comprises an optical element formed of a birefringent crystal material and which, by means of the optical element, splits signal light to be measured into a plurality of polarized light beams and adjusts the polarization state of one or more among the plurality of polarized light beams, and a light-receiving portion for performing photoelectric conversion of an optical component of the signal light split by and emitted from the polarization splitting device.

Stokes parameter measurement device and method

An object is to accurately measure the Stokes parameters, without the occurrence of polarization fluctuations or PDL during the splitting of the incident light. When the incident light is made incident on a first-stage prism, the light is split into two first splitting light rays. Next, the first split light rays are respectively incident on a pair of prisms of a second stage. Each of the pair of first split light rays is split into two rays by a second-stage prism, to obtain four second split light rays.

An image forming apparatus includes an image forming portion for forming an image, an image reading portion for reading an image, displaceable with respect to the image forming portion, and an open/closable member that can be opened or closed with respect to a main body of the image forming portion and displaced toward the image reading portion, wherein the displacement of the open/closable member is effected in relation to the displacement of the image reading portion. In this manner the open/closable member can be opened or closed by a simple operation, without increasing the dimension of the image forming apparatus.

Image forming apparatus

A semiconductor luminous element has cladding layers on both sides of its active layer; and it has a multi-quantum barrier layer which is in contact with the active layer on at least a portion of at least one of the cladding layers. This multi-quantum barrier layer is formed of an alternating stack of superlattice barrier layers and superlattice well layers. The energy gap of the well layers is smaller than that of the active layer, and the quantized energy gap of the multi-quantum barrier layer is larger than the energy gap of the active layer. A superlattice structure for semiconductor devices, which confines electrons and holes, is formed out of the active layer and a cladding layer provided on at least one side of that active layer. A multi-quantum barrier layer is in contact with the active layer on at least a portion of the cladding layer. This multi-quantum barrier layer is formed of an alternating stack of superlattice barrier layers and superlattice well layers. The energy gap of the well layers is smaller than that of the active layer, and the quantized energy gap of the multi-quantum barrier layer is larger than the energy gap of the active layer.

Semiconductor luminous element and superlattice structure

Disclosed is an apparatus utilizing a light emitting semiconductor device which has a pumped region and an unpumped absorber region and in which an active layer has a quantum well structure. In this light emitting semiconductor device, driving current/light output characteristics have dependence on the pulse width of a driving current. A logic unit or a noise reducing apparatus is realized utilizing this property. Furthermore, in the above described light emitting semiconductor device, the central wavelength of emitted light has dependence on a driving current or dependence on driving time. A light beam scanner can be realized utilizing this property.

Apparatus utilizing light emitting semiconductor device

Growing community of inventors

Tokyo, Japan

Takeshi Takagi