Hitachi, Ltd.

Hitachi Chemical Company, Ltd.

Other

Nichia Corporation

Hitachi Cable, Inc.

Hitachi, Litd.

Hirohisa Sano

Tatemi Ido

Katsuyuki Imoto

Shigeki Kitajima

Tatsuo Kanetake

Kimio Tatsuno

Shoichi Hanatani

Makoto Takahashi

Takeshi Shimano

Masahiro Takatori

Minoru Maeda

Yasuyuki Fukashiro

Yukio Hayashi

Hiroaki Inoue

Masahide Tokuda

Hideaki Tsushima

Shigeharu Kimura

Makoto Suzuki

Takeshi Maeda

Toshiaki Tanaka

Shigeru Nakamura

Shinji Nishimura

Akira Arimoto

Akihiko Takase

Shinya Sasaki

Masahiro Aoki

Yasuo Hira

Kazuhisa Uomi

Masaru Miyazaki

Shinji Sakano

Yoshitaka Takasaki

Hisato Uetsuka

Koji Ishida

Masaki Ohira

Tomoaki Shibata

Atsushi Takai

Nobuo Miyadera

Masato Shishikura

Koji Yoshida

Hideaki Takano

Katsuhiko Kuboki

Toshio Kirihara

Hiroyuki Gomyo

Naoyuki Matsuoka

Mari Ogawa

An integrated optical head records and reproduces information to and from optical discs of different types, including CD and DVD, with use of a single information recording/reproducing apparatus. The optical head has a plurality of semiconductor lasers of different wavelengths integrated by index alignment onto a substrate formed with an optoelectric integrated circuit, photodetection patterns, and a reflecting mirror.

Optical head with lasers and mirrors in a recess formed in a substrate

The present invention provides an optical module using optical waveguides which permits easy fabrication of a PLC type optical multiplexer/demultiplexer with reduced loss. The optical module comprises cores which are contiguous to each other through a dicing groove adapted to position and fix an optical functional part such as a wavelength selection filter and a core branched from the said cores. A slight gap is present between the former and the latter core and both cores are narrower in width in the vicinity of the dicing groove than the other portions.

Optical waveguide apparatus

An optical crossconnect apparatus which includes one terminal connected to a transmission path from one optical transmission terminal station and another terminal connected to a transmission path from another optical transmission terminal station, a first optical signal switch having 'M' ports and 'N' ports, through which the optical signal can pass, a second optical signal switch having &#x201c;M&#x201d; ports and &#x201c;N&#x201d; ports, through which the optical signal can pass, and &#x201c;L&#x201d; optical signal repeaters, one end connected to the &#x201c;N&#x201d; ports of the first optical signal switch, and the other end connected to the &#x201c;N&#x201d; ports of the second optical switch. The &#x201c;N&#x201d; and the &#x201c;N&#x201d; ports are equal to &#x201c;L&#x201d; optical signal repeaters. The &#x201c;M&#x201d; ports of the first optical signal switch connected to the one terminal, and the &#x201c;M&#x201d; ports of the second optical signal switch connected to the other terminal are larger than, or equal to 2.

Optical crossconnect apparatus and optical transmission system

A method of mounting an optical device having a step on the surface opposing to a mounting substrate favorably by face-down bonding which enables a decrease in the number of components or integrate additional components on one identical substrate and, accordingly, is useful for reducing the size and the thickness of an optical head using a light source, the method includes the step of making the volume of a solder pattern to the area ratio of each electrode different for every wiring electrode portions upon mounting the electrodes on the substrate for mounting the optical device, in which the optical device having the step can be mounted favorably to the substrate by the control for the height of solder upon melting.

Mounting method for optical device and optical head equipment

An optical transmitter/receiver module of wavelength division multiplexing type which undergoes a reduced excess loss resulting from the displacement of a dicing position is fabricated with a high yield rate. An optical waveguide for guiding reflected light from a wavelength selection filter has a core substantially larger in size than the core of each of the other optical waveguides.

Optical waveguide and their application of the optical communication system

An optical crossconnect apparatus which includes one terminal connected to a transmission path from one optical transmission terminal station and another terminal connected to a transmission path from another optical transmission terminal station, a first optical signal switch having &ldquo;M1&rdquo; ports and &ldquo;N1&rdquo; ports, through which the optical signal can pass, a second optical signal switch having &ldquo;M2&rdquo; ports and &ldquo;N2&rdquo; ports, through which the optical signal can pass, and &ldquo;L&rdquo; optical signal repeaters, one end connected to the &ldquo;N1&rdquo; ports of the first optical signal switch, and the other end connected to the &ldquo;N2&rdquo; ports of the second optical switch. The &ldquo;N1&rdquo; and the &ldquo;N2&rdquo; ports are equal to &ldquo;L&rdquo; optical signal repeaters. The &ldquo;M1&rdquo; ports of the first optical signal switch connected to the one terminal, and the &ldquo;M2&rdquo; ports of the second optical signal switch connected to the other terminal are larger than, or equal to 2.

This invention is provided to reduce wavefront aberrations caused by the filling of a transparent resin intended to prevent degradation of a diode laser in a hermetically sealed package. A parallel-plane plate is arranged between a diode laser and an objective lens, and a transparent resin is filled into a space formed between the diode laser and the parallel-plane plate. With this invention, degradations of the diode lasers can be prevented and the wavefront aberrations can be reduced.

Diode laser module and application equipment

A conventional problem is to provide an optical module capable of being reflow mounted together with electronic components collectively, and, at the same time, securing a mechanical strength that can bear a large stress at the time of an attachment/detachment of the optical fiber. A solution to the above-mentioned problem can be attained by using an optical connector removable type optical module for reflow mounting having a fixing structure for fixing itself to a mount board, including a receptacle part installed to an optical module to which an optical connector is detachably connected; electric terminals for reflow mounting that are arranged corresponding to lands on a mount board ; and stud parts that are able to fit in fixing holes on the mount board

Optical module, board mounted optical module, and assembly method of optical module

Input/output fibers for the optical cross-connect system are classified into working fibers and protecting fibers. In a normal time (a state in which there occurs no failure), there turns out to be a one-to-one correspondence between a line terminal and a working fiber. Namely, connection property required for the switch matrix in the optical cross-connect system is not necessarily strictly non-blocking connections among all of the fibers. The connection property is a one-to-one connection relationship with the working fibers, and is a predetermined connection relationship with the protecting fibers at the time of a failure occurrence. Utilization thereof makes it possible to extremely downsize scale of the switch.

Optical cross-connect system and optical transmission system

A semiconductor optical device, a fiber optical amplifier and an optical transmission system are disclosed. The semiconductor optical device is excellent in the stability of the coupling efficiency and the splitting ratio of a Y-branch. Both the fiber optical amplifier and the optical transmission system operate in a stable manner over a long period of time even if an optical waveguide is employed which is operative in a multi-mode in the transverse direction. The semiconductor optical device has an optical waveguide, a mode filter for transmitting therethrough light of a fundamental mode and blocking the propagation of light of a higher-order mode. The mode filter is provided in at least a part of the optical waveguide. The width of the mode filter is larger than that of the optical waveguide.

Semiconductor optical device, fiber optical amplifier and optical

In the structure of the device of the invention, a supper-lattice buffer layer is formed between the undoped layer and doped layers. This super-lattice buffer layer serves as a carrier-piling up layer in place of the undoped layer in the conventional device. Thus, the amounts of the piled-up carriers in the undoped layer can be greatly reduced and hence no band filling effect occurs in the undoped layer. Consequently, an optical device having a flat frequency characteristic can be produced without losing its modulating characteristic.

Non-uniform thickness or bandgap superlattice betweeen cladding layer

A passive region is provided on one side or both sides of a waveguide-type optical modulator. Thereby, it is possible to obtain a high-speed optical modulator package superior in mechanical strength, thermal characteristic, high-frequency characteristic, and extinction characteristic. Moreover, it is possible to increase the operating speed of an optical fiber transmission equipment by applying the optical modulator package to the optical fiber transmission equipment.

Semiconductor optical modulator

To obtain an optical functional device such that the reflectivity of a facet and the loss of coupling with a fiber are reduced, a mode conversion region for changing the beam spot size is formed on the input facet and/or the output facet in an optical function region and the facet of the side to be connected with a fiber in the mode conversion region is formed obliquely to the direction of propagation of light.

Semiconductor optical functional device

Disclosed is a semiconductor optical integrated device and method of fabricating the device, the device having a plurality of quantum well structures, formed on a single substrate, acting as optical waveguides, the plurality of quantum well structures respectively having different lattice mismatches with the substrate and/or different strains (e.g., respectively compressive strain and tensile strain). The method includes selectively depositing the quantum well structures by, e.g., organometallic vapor phase epitaxy on growth regions of the substrate, the growth regions being defined by insulating layer patterning masks, with a width of the growth regions and/or a width of the patterning mask being different for the different quantum well structures. Each quantum well structure includes quantum well layers of III-V or II-VI compound semiconductor material, the Group III or Group II elements each including at least two elements, one having a relatively large atomic diameter and another having a relatively small atomic diameter. Also disclosed is a light receiver that can independently absorb TE-mode and TM-mode light in series, which can be used in a polarized-wave diversity receiver for coherent optical communication.

Semiconductor optical integrated device and light receiver using said

Growing community of inventors

Niiza, Japan

Hirohisa Sano