Fujitsu Corporation

Fujitsu Optical Components Limited

Tetsuo Ishizaka

Masaharu Doi

Manabu Komiyama

Takehito Tanaka

Shunichi Satoh

Saeko Yokoi

Toshio Ohya

Takayuki Masuko

Shunichi Sato

Shuuichi Miyawaki

Noboru Sonetsuji

Tadao Nakazawa

Takashi Tsuda

Shinji Maruyama

Noriaki Mizuguchi

Minoru Seino

Yasuhiro Ohmori

Yasunori Nagakubo

Koji Otsubo

Teruhiro Kubo

Yoshihiko Kaitoh

Tomoyuki Ito

Tomonori Azuma

Yuka Ojima

An optical module includes: a first board having an optical component bonded thereto with an adhesive; a connection structure part rising from the first board and made of a material having lower thermal conductivity than thermal conductivity of a material of the first board; and a second board joined to the connection structure part.

Optical module

An optical module includes: a board that is accommodated in a housing and in which a through hole is formed; a metal plate that is bonded to an area of the board including the through hole; a component that is mounted on one surface of the metal plate and is arranged inside the through hole; and a thermal-conductive member that is arranged on another surface of the metal plate and transmits heat generated by the component to the housing.

An optical transmission module includes: a bias current drive circuit to drive a bias current of a light-emitting element, on a basis of an input bias current setting value; a modulation current drive circuit to drive a modulation current of the light-emitting element, on a basis of an input modulation current setting value; a light-receiving element to measure an optical output power of the light-emitting element; a determiner to determine whether a difference between a target value of the optical output power and the optical output power measured by the light-receiving element is equal to or more than a threshold; and a controller configured to perform a correction control to the bias current drive circuit so that the bias current is reduced in accordance with the difference, when it is determined that the difference is equal to or more than the threshold by the determiner.

Optical transmission module and control method of optical transmission module

A light source module includes a single light source with two opposite light outputting faces, a first optical amplifier and a second optical amplifier provided on opposite sides of the light source adjacent to the corresponding light outputting faces, and a first monitor configured to monitor an output of the first optical amplifier, wherein a power output level of the first optical amplifier is controlled independently from the second optical amplifier based upon a monitoring result of the first monitor.

Light source module and optical transceiver

An optical transmission module includes a bias current driver circuit adapted to input bias current set in response to a temperature of a laser diode to the laser diode, a modulation current driver circuit adapted to input modulation current set in response to the temperature of the laser diode to the laser diode, and a decision circuit adapted to decide whether or not an error of optical output power of the laser diode detected by a light reception device with respect to a target value of the optical output power of the laser diode at the set bias current and the set modulation current is equal to or higher than a threshold value. The modulation current driver circuit inputs, while the error is equal to or higher than the threshold value, correction modulation current higher than the set modulation current to the laser diode.

Optical transmission module and controlling method for optical transmission module

The present invention has an object to provide an optical device capable of leading out a light propagated through an optical waveguide to a desired substrate side face while maintaining the sufficient power of the light, within a range of limited substrate size. To this end, according to the optical device of the present invention, a groove is formed in the vicinity of an end portion on the optical output side of the optical waveguide, on the substrate on which the optical waveguide is formed, a side wall of the groove is used as a reflecting plane, the light output from the optical waveguide is reflected by the reflecting plane, and the reflected light is emitted from the desired substrate side face.

Optical waveguide device

The invention provides an optical modulator wherein appearance of radiation mode light can be suppressed to improve performances as a device. The optical modulator includes a multiplexing waveguide which in turn includes two input waveguides to which propagation lights from a linear waveguide are inputted, a waveguide coupling element, and two output waveguides. The width of the waveguide coupling element on the input side is greater than the total width of the two input waveguides, and the width of the waveguide coupling element on the output side is greater than the total width of the two output waveguides. The device of the present invention is applied typically to an optical communication system.

Optical modulator, optical waveguide device and acousto-optic tunable filter apparatus

A first optical waveguide, a second optical waveguide, a first electrode, and a second electrode are integrated on a substrate. An optical modulator is provided with a clock signal generator for generating an RZ signal by applying a clock signal to either the first or second electrode, and an NRZ data signal generator for supplying an NRZ data signal to the remaining electrode. Thus, the space required by the optical modulator is reduced while tolerance of the same is improved, thus reducing costs for constructing the optical modulator.

Optical modulator of clock modulation type

The present invention relates to an optical modulator allowing appropriate interaction between signal electrodes and an optical waveguide, only by matching phases at input ends of the signal electrodes. The optical modulator includes an optical waveguide with its center part branched into two at two Y-branch waveguides, forming first and second waveguide arms, a first signal electrode transmitting a first electric signal interacting with first light propagating through the first waveguide arm in a predetermined manner, a second signal electrode transmitting a second electric signal interacting with second light propagating through the second waveguide arm in a predetermined manner, and earthed electrodes, and can match the interacting timing between the first electric signal and the first light to the interacting timing between the second electric signal and the second light, at a first input end supplying the first electric signal and a second input end supplying the second electric signal.

Optical modulator

The optical module has an element mounted thereupon for shifting an optical phase by the electro-optic effect, and includes an element for shifting an optical phase by an electro-optic effect having a signal electrode and a ground electrode formed thereupon; a connector for supplying a control signal of a microwave region to the signal electrode of the element, having a center conductor and an outer conductor; and a repeating board formed on a dielectric wafer having a coplanar line connecting the signal electrode and the ground electrode with the center conductor and the outer conductor of the connector respectively on the dielectric wafer, wherein an air layer is formed on the lower portion of the repeating board on which the center conductor of the connector is disposed.

Growing community of inventors

Kawasaki, Japan

Tetsuo Ishizaka