The Furukawa Electric Co., Ltd.

Takeshi Aikiyo

Toshio Kimura

Junji Yoshida

Naoki Tsukiji

Masashi Nakae

Takashi Koseki

Takahiro Okada

Hiroshi Matsuura

Takeo Shimizu

Masaki Funabashi

Tomoaki Toratani

Toshiro Yamamoto

Mieko Konishi

Satoshi Koyanagi

Chihomi Furuhashi

Naoki Kimura

Hiroyuki Matsuura

Hiroshi Ichikawa

Takashi Shigematsu

Jun Miyokawa

Masaru Saito

Hideaki Murata

Yoshikazu Ikegami

Toru Fukushima

Jun Niekawa

Masato Sakata

Shinichiro Iizuka

Yusei Shirasaka

Kazuto Ono

Masayoshi Seki

Kohei Terada

Yukio Kazama

Kaoru Iida

Akira Iketani

A semiconductor laser module has a semiconductor laser device; a package for housing the semiconductor laser device; a PBC fixed in the package for polarization-synthesizing two laser beams output from the semiconductor laser device; a depolarizing element fixed in the package for depolarizing a synthesizing light output from the PBC; and an optical fiber for receiving a light output from the depolarizing element.

Semiconductor laser module, optical amplifier, and method of manufacturing the semiconductor laser module

A semiconductor laser device having two active-layer stripe structures includes an n-InP substrate, an n-InP clad layer, a lower GRIN-SCH layer, an active layer, an upper GRIN-SCH layer, a p-InP clad layer, and a p-InGaAsP contact layer grown in this order, in a side cross section cut along one of the stripe structure. A high-reflection film is disposed on a reflection-side end surface, and a low-reflection film is disposed on an emission-side end surface. A p-side electrode is disposed on only a part of the upper surface of the p-InGaAsP contact layer so that a current non-injection area is formed on an area absent the p-side electrode.

Semiconductor laser device, semiconductor laser module, and optical fiber amplifier using the semiconductor laser module

A method and apparatus for inspecting a plurality of optical modules, in which the optical modules are given channel numbers, a plurality of inspection items, which are related to optical characteristics and/or electrical characteristics of the optical modules, are measured in parallel, and measurement data on the inspection items is stored in storing device. This makes it possible to inspect the optical modules efficiently in a short time, eliminating waiting time.

Method and apparatus for inspecting optical modules

An optical module includes a package; an optical device housed in the package, and having a temperature-dependent characteristic; a thermo-module connected to the optical device to control its temperature and configured to heat or cool the optical device when supplied with a first electric current in one direction or a second electric current in a direction opposite to the first electric current, respectively; and a heating element disposed close to the optical device and configured to heat the optical device when supplied with an electric current.

Optical module, optical apparatus including optical module, and method for using optical module

The invention provides a semiconductor laser module which can suppress overcurrent flowing into a thermo-module, wherein the thermo-module () carries out a heating action when a reverse current flows from lead pin () through lead pin (), and contrarily carries out a cooling action when a current flows from the lead pin () through the lead pin (). An overcurrent limiting means () is provided, which can suppress overcurrent flowing into the thermo-module () in its heating direction. The overcurrent limiting circuit () is provided with a bypass line (), a resistor (), and a diode (). When a current flows in the heating direction, the diode () is turned on, whereby the current is shunted to the thermo-module () and bypass line () for flow, and accordingly, the overcurrent flowing into the thermo-module () can be effectively suppressed.

Semiconductor laser module, and method for driving the semiconductor laser module

A semiconductor laser device and module for use in a dense wavelength division multiplexed optical communications system are shown. The laser device preferably has cavity lengths greater than 1000 &#x3bc;m, and compressive strain multi-quantum well active layer, and front-facet reflectivity of less than about 4%. Higher optical outputs by longer cavity lengths are achieved. Preferred modules use these laser diodes with external wavelength-selective reflectors that have narrow bandwidths of 3 nm or less, and which include a plurality of longitudinal mode subpeaks within the bandwidth. Relationships between reflectivity value of the front facet and the peak reflectivity of the wavelength-selective reflector for long cavity length laser device are also disclosed, with the relationships providing higher output power along with a stabilized output spectrum.

Semiconductor laser devices, and semiconductor laser modules and optical communication systems using the same

A single semiconductor laser device used in a semiconductor laser module of an optical amplifier and having a first light emitting stripe with a diffraction grating and at least one other light emitting stripe with a diffraction grating and which are aligned to respectively emit a first laser beam and at least one other laser beam through one edge surface.

Semiconductor laser device for use in a semiconductor laser module and an optical amplifier

A semiconductor laser module includes a single semiconductor laser device having a first light emitting stripe and at least one other light emitting stripe which are aligned to respectively emit a first laser beam and at least one other laser beam through one edge surface. It also includes a first lens positioned so that the first laser beam and the at least one other laser beam emitted from the semiconductor laser device are incident thereon, the first lens configured to separate the first laser beam and the at least one other laser beam. A beam synthesizing member is included and has a first input part on which the first laser beam is incident, at least one other input part on which the at least one other laser beam is incident, and an output part from which the first laser beam emerging from the first input part and the at least one other laser beam emerging from the at least one other input part are multiplexed and emitted as a multiplexed laser beam. An optical fiber is positioned to receive the multiplexed laser beam therein.

Semiconductor laser module, manufacturing method thereof and optical amplifier

A semiconductor laser module is packaged on a mounting substrate through a thermal diffusion sheet member. The thermal diffusion sheet member is that having thermal conductivity where thermal conductivity in the surface direction is greater than that in the thickness direction. Specifically, the thermal diffusion sheet member is graphite, for example, and has a thermal conductivity of 300 W/m&middot;K or greater in the surface direction.

Mounting structure for semiconductor laser module

A bottom plate ( ) of a box-shaped package ( ) is made of a metal. Portions of the package ( ) (peripheral wall ( ) and cover plate ( )) other than the bottom plate ( ) are made of a resin or a ceramic that is more economical than the metal. The material cost of the package ( ) can thus be reduced in comparison with the case where the package ( ) is made of the metal as a whole. A Peltier module ( ) is fixed to the bottom plate ( ). A base ( ) is fixed over the Peltier module ( ), and a semiconductor laser chip ( ) is disposed on this base ( ). Heat from the semiconductor laser chip ( ) and from the Peltier module ( ) can be efficiently radiated through the bottom plate ( ) made of the metal, and deterioration of heat radiation performance can be prevented.

Semiconductor laser module with peltier module for regulating a temperature of a semiconductor laser chip

A semiconductor laser device and module for use in a dense wavelength division multiplexed optical communications system are shown. The laser device preferably has cavity lengths greater than 1000 &mgr;m, and compressive strain multi-quantum well active layer, and front-facet reflectivity of less than about 4%. Higher optical outputs and longer cavity lengths are achieved. Preferred modules use these laser diodes with external wavelength-selective reflectors that have narrow bandwidths of 3 nm or less, and which include a plurality of longitudinal mode subpeaks within the bandwidth. Relationships between reflectivity value of the front facet and the peak reflectivity of the wavelength-selective reflector for long cavity length laser device are also disclosed, with the relationships providing higher output power along with a stabilized output spectrum.

In the semiconductor laser device of the present invention, a semiconductor stacked structure including an active layer comprising a strained multi-quantum well structure is formed on a substrate a cavity length is larger than 1000 &mgr;m but equal to or smaller than 1800 &mgr;m, and a low-reflection film S having a reflectance of 3% or less is formed on one facet and a high-reflection film S having a reflectance of 90% or more is formed on the other facet. The semiconductor laser module has a structure in which the semiconductor laser device is set to a cooling device constituted by electrically alternately arranging 40 pairs or more of the Peltier elements and holding them by top and bottom ceramic plates and sealed in the package. A grating having a reflection bandwidth of 1.5 nm or less is formed on an optical fiber to be built in.

Semiconductor laser device and semiconductor laser module using the same

An optical communication device which has an optical module including an optical element and a lens system optically coupled through a space and housed in a package, a supporting member for supporting the optical module, and a fixing member directly placed over the optical module for removably fixing the optical module on the supporting member, wherein the optical module is securely sandwiched between the supporting member and the fixing member, and a method of fixing the optical module for use in the optical communication device.

Optical communication device and method of fixing optical module

The present invention provides a method for hermetically sealing a semiconductor laser element, by which the cleanness of a package can be maintained extremely satisfactorily in a stabilized state, in order to prevent organic substances from being adhered to the end faces of high output semiconductor laser elements due to photochemical actions. The method comprises the first step of introducing oxygen into a chamber of a hermetical-sealing apparatus and irradiating ultraviolet rays onto an unsealed package having a semiconductor laser element mounted, in the chamber, and the second step of purging the chamber with an inert gas and hermetically sealing an unsealed package in the inert gas atmosphere without being exposed to the outer atmosphere.

Growing community of inventors

Tokyo, Japan

Takeshi Aikiyo