Abstract: The present invention provides a optical module comprising a semiconductor laser diode for outputting a laser beam; a first carrier on which the semiconductor laser diode is fixedly mounted; a photodiode for receiving a monitoring laser beam outputted from the back face of the semiconductor laser diode; a second carrier on which the photodiode is fixedly mounted; and a base on which the first and second carriers are fixedly mounted through soldering. At least one soldering sheet for soldering the first and second carriers on the base is fixedly pre-mounted on the base in place through spot welding.

Abstract: An optical amplifier of the present invention comprises a pumping light source configured to output a pumping light, an amplifier unit configured to receive the pumping light from said pumping light source and amplify an optical signal that passes therethrough, and an optical fiber disposed between said pumping light source and said amplifier unit, said optical fiber including an optical filter that is configured to attenuate the optical signal from said amplifier unit.

Abstract: An optical waveguide circuit device strong in impact strength in dropping, etc. is provided. A waveguide pattern is formed on a silicon substrate in this optical waveguide circuit device. For example, this waveguide pattern has an optical input waveguide, a first slab waveguide, an arrayed waveguide including a plurality of channel waveguides having lengths different from each other and arranged side by side, a second slab waveguide, and a plurality of optical output waveguides arranged side by side. The first slab waveguide is separated on a cross separating face crossing an optical path passing the first slab waveguide. A temperature dependence in light transmission central wavelength of an arrayed waveguide grating is reduced by sliding and moving a separating slab waveguide side by a slide moving member along the separating face depending on temperature.

Abstract: An optical waveguide circuit having a waveguide core of a desired shape formed on a substrate and method of fabricating same. The optical waveguide circuit is manufactured in a manner such that light confinement portions having substantially the same refractive index as the waveguide core are arranged along one or both sides of the waveguide core. The waveguide core and the light confinement portions are formed simultaneously.

Abstract: A heat sink including a heat dissipating fin comprises (1) a heat dissipating fin having a plurality of mountain-shaped portions and base portions supporting the mountain-shaped portions, (2) a base member having a plurality of slits into which the mountain-shaped portions of the heat dissipating fin are to be inserted and a plurality of holes for fixing the heat dissipating fin, and (3) a fitting member, provided with a plurality of projecting portions corresponding to the plurality of holes of the base member, for fixing the heat dissipating fin between the base member and the fitting member itself.

Abstract: An optical fiber cable capable of absorbing water and resisting any undesirable increase of transmission loss caused by temperature variations. It has a core assembly formed by surrounding a stack of cores (1) in e.g. ribbon form by a shock absorbing member (2), at least one member (3) of high tensile strength and a sheath (4) formed from e.g. a thermoplastic resin and enclosing the core assembly and the high-tensile member (3). The shock absorbing member (2) is a strand of e.g. yarn not absorbing water, but carrying a water-absorbing resin.

Abstract: A DFB Laser of buried hetero type with a lasing wavelength of 1550 nm, having on an InP substrate a laminated structure of an InP buffer layer, an active layer, a 200-nm-thickness InP spacer layer, a 240-nm-period diffraction grating made of a 20-nm-thickness GaInAsP layer, and an InP first cladding layer in which diffraction grating is buried. The peak wavelength &lgr;max of the optical gain distribution of the active layer is approximately 1530 nm. The bandgap wavelength of the diffraction grating is approximately 1510 nm. The laminated structure is etched into mesa stripes, on both sides of which are formed p/n-separated current blocking regions, Since the diffraction grating is formed of GaInAsP having &lgr;g of approximately 1510 nm, little absorption occurs at wavelengths around the lasing wavelength 1550 nm.

Abstract: The invention provides a semiconductor laser module of high output in which the radiating property of heat generated from a semiconductor laser element is high, and power consumption is small. In this semiconductor laser module, a base is arranged on a Peltier module, and has a basic portion having a face fixed to the Peltier module and a stem supporting portion rising on the basic portion. The base is formed by a material having a preferable coefficient of thermal conductivity. An internal module has the semiconductor laser element attached to a stem, an optical fiber for receiving a laser beam, and a member such as a lens for coupling the laser beam to the optical fiber. When this internal module is fixed to the base, the stem comes in contact with a stem supporting face of the stem supporting portion, and is fixed to the stem supporting face. The heat generated from the semiconductor laser element is directly transmitted from the stem to the base without passing a cap attached to the stem.

Abstract: An electrical connection box has upper and lower casings capable of being combined with each other, a wiring board located between the casings and having a plurality of independent electric circuits, and an insulating plate located between the upper casing and the wiring board. The upper casing is formed with a connector housing to be fitted with an external connector, and external connecting terminals coupled to the electric circuits and electrically connecting the electric circuits and the external connector or an L-shaped rib formed on the wiring board and capable of preventing the external connector from being fitted in the connector housing projects into the connector housing.

Abstract: There is disclosed a method of producing an aluminum alloy for automotive parts, comprising adding a scrap of an aluminum wrought alloy or a pure aluminum ingot to an aluminum alloy casting scrap, melting the mixture to dilute impurities, and if necessary, adjusting elements of the resultant. According to the above method, aluminum alloy casting scraps, which contain large amounts of impurities and have been difficult to recycle into other articles until now, can be converted to an aluminum alloy material that is applicable as a wrought material usable as a higher-grade material.

Abstract: An optical semiconductor device module includes an optical semiconductor device package, an optical semiconductor device such as a laser diode accommodated in the package, and a cooling device such as a Peltier device solder-joined to a solder joint area on an inner face of a metal bottom plate of the package and operable to cool the optical semiconductor device. A groove permitting molten solder to flow therein is formed in at least part of the solder joint area on the inner face of the metal bottom plate.

Abstract: A connector adapter including a light emitting element for emitting a laser beam and connected with a plug having an optical fiber, whereby the laser beam emitted from the light emitting element is introdued into the optical fiber. The connector adapter comprises a shutter member fixed in a connector and including a base portion having a first spring portion and a shutter portion connected to the base portion. The base portion undergoes elastic deformation at the first spring portion so that the shutter portion recedes from the optical path of the laser beam when the plug is pushed into the adapter to be attached thereto, and is restored from the elastic deformation so that the shutter portion intercepts the optical path of the laser beam when the plug is drawn out of the adapter to be detached therefrom.

Abstract: Disclosed is a wavelength multiplexing module which provides stable multiplexed output power. The wavelength multiplexing module comprises a plurality of pumping sources for outputting lights of different wavelengths, and a wavelength multiplexer for multiplexing the lights output from the pumping sources. The wavelength multiplexer is provided with optical input sections for respectively receiving the lights output from the pumping sources. Respectively provided between the optical input sections and the pumping sources are depolarizers each of which causes a degree of polarization of the light output from an associated one of the pumping sources to approach zero. Each depolarizer has two polarization-maintaining optical fibers connected in series on an optical path in such a way that primary optic axes of the polarization- maintaining optical fibers obliquely intersect each other.

Abstract: An arrayed waveguide grating type optical multiplexer/demultiplexer of the invention eliminates the temperature dependency of the light transmission center wavelengths and suppresses an increase in insertion loss with a simple configuration even under the conditions of high temperature and high humidity. A waveguide forming area comprising an optical input waveguide, a first slab waveguide, an arrayed waveguide formed of a plurality of channel waveguides arranged side by side having a different length each other, and a plurality of optical output waveguides connected one by one is formed on a substrate. For example, the first slab waveguide is separated at crossed separation planes that cross the path of light passing through the first slab waveguide. On the crossed separation planes, a matching grease is applied. A thin film member for covering the area arranged with the matching grease is disposed to suppress the evaporation of the matching grease.

Abstract: The present invention relates to an optical waveguide circuit such as an arrayed waveguide grating, etc., which is capable of suppressing influences of polarization dependency loss without providing a half-wave plate. A lower cladding is formed on a silicon substrate. A core having the following waveguide construction is formed thereon. That is, an input side slab waveguide is connected to the emission side of a plurality of incidence waveguides, a plurality of arrayed waveguides having different lengths form each other are juxtaposed at and connected to the emission side thereof, an output side slab waveguide is further connected to the emission side thereof, and a plurality of emission waveguides are connected to the emission side thereof, thereby causing the abovementioned waveguide construction. The upper cladding covers up the core.

Abstract: A ferrule fixed module of the invention has the high aligning fixing accuracy of a ferrule to a coupling counter part and is low costs. Additionally, the ferrule fixed module of the invention can shorten the fabrication time thereof. The coupling end surface side of a lensed fiber (8) inserted and fixed to a first ferrule (4a) is faced to a laser diode chip (3) in the aligned state and the ferrule (4a) is fixed to a base (1) through a ferrule fixing component (10). The ferrule fixing component (10) is formed of clamping parts (6) having paired arm parts (12) for clamping and fixing the ferrule (4a) at the parts near the laser diode chip (3) from both sides of side parts and clamping parts (7) having paired arm parts (13) for clamping and fixing the ferrule (4a) at the parts far from the laser diode chip (3) from both sides of the side parts.

Abstract: First pump light for Raman-amplifying optical signal is inputted to the output end of the optical signal, and second pump light used for Raman-amplifying the first pump light and having a wavelength shorter than that of the first pump light is inputted to the input end of the optical signal. The second pump light is also inputted to the output end of the optical signal. The first pump light is also inputted to the input end of the optical signal. The Raman amplification band of the second pump light is made not to be overlapped with that of the optical signal. The wavelength of the second pump light is shorter than that of the first pump light by the Raman shift of the amplifier fiber. The light source of either the first or second pump light or both the light sources of them are multiplex optical sources. The first pump light is emitted from a semiconductor laser. Third pump light for Raman-amplifying the second pump light is directed to an optical transmission line.

Abstract: A passivation layer suppresses an output end face of a semiconductor laser having a band of an oscillation wavelength of 980 nm from being degraded and contributes to securance of the long-term reliability of the semiconductor laser. In a passivation layer, for a semiconductor laser, having a two-layered structure and constituted by a first thin film directly formed on the output end face of the semiconductor laser and a second thin film formed on a surface of the first thin film, the thickness of the first thin film is set such that, in a calculation expression for calculating the reflectance of the passivation layer by a matrix method, a differential coefficient obtained when the calculation expression is differentiated by the film thickness of the first thin film is zero.

Abstract: A Raman amplifier according to the present invention comprises a plurality of pumping means using semiconductor lasers of Fabry-Perot, DFB, or DBR type or MOPAs, and pumping lights outputted from the pumping means have different central wavelengths, and interval between the adjacent central wavelength is greater than 6 nm and smaller than 35 nm. An optical repeater according to the present invention comprises the above-mentioned Raman amplifier and adapted to compensate loss in an optical fiber transmission line by the Raman amplifier. In a Raman amplification method according to the present invention, the shorter the central wavelength of the pumping light the higher light power of said pumping light.

Abstract: Disclosed is a field distribution converting optical fiber which can be massproduced and enables mutual conversion elliptical field distribution to circular field distribution or vice versa, and a laser diode module in which the field distribution converting optical fiber is used. The optical axis is assumed to be Z, either of the refractive index profiles of a core in the X and Y directions of the orthogonal three axes X, Y and Z is made into a square-law distribution profile, a slope of the refractive index profile in the corresponding X direction is made different from a slope of the refractive index profile in the Y direction. The optical axis propagating in the XZ and XY planes is caused to cyclically change in the Z direction, wherein these cycles are made different from each other to cause the cross-sectional profile of the field distribution of the optical fiber to be cyclically changed.