Matsushita Electric Industrial Co., Ltd.

Masanori Iida

Hiroyuki Asakura

Hisashi Adachi

Masaki Kobayashi

Mikihiro Shimada

Tsuguhiro Korenaga

Tetsuji Miwa

Masaaki Tojo

Noboru Kurata

Minoru Nishioka

Hikaru Ikeda

Hironori Souda

Naoki Takenaka

Kiyokazu Hagiwara

Koichi Murase

Tetuji Miwa

A first substrate on which an optical-waveguide groove is formed and a second substrate. The second substrate is bonded to the plane of the first substrate on which the optical-waveguide groove is formed by a material having a refractive index higher than those of the first substrate and second substrate. The optical-waveguide groove is filled with the material, and the refractive index of the first substrate is different from the refractive index of the second substrate.

Optical waveguide and method of forming the same

Transmitting circuit apparatus and method

A transmitting circuit apparatus has a first digital modulator and a second digital modulator for modulating an I signal and a Q signal which are multi-valued digital baseband modulation signals, into a digital I signal and a digital Q signal, respectively, having the number of bits smaller than that of the baseband modulation signals; and a quadrature modulator for outputting a signal synthesized from the signals generated by modulating (two) carrier waves each having a phase perpendicular to each other by using the modulated I and Q signals, respectively.

Wireless quadrature modulator transmitter using E/O and O/E connectives

An optical mount substrate and a manufacturing method of the optical mount substrate. An optical fiber guide section for arranging and fixing an optical transfer section, having an optical waveguide or an optical fiber, is formed. An electrical conductivity member is embedded in the optical mount substrate so that it penetrates a first principal plane of an arrangement section for arranging an optical device optically connected with the optical waveguide or the optical fiber on the first principal plane, and a second principal plane of the arrangement section parallel to the first principal plane. The optical fiber guide section and the arrangement section are formed by pressing a mold member to a heated and softened substrate to transfer inversion geometry of the mold member onto the substrate. The electrical conductivity member, having a predetermined shape, is directly pressed onto the heated and softened substrate to embed it into the substrate.

Optical mount substrate, optical module, optical transmitter-receiver, optical transmitter-receiver system, and manufacturing method of optical mount substrate

Optical module and manufacturing method thereof

An optical element has a substrate having or not having a channel for optical waveguide; and a material which has a refractive index higher than that of the substrate and is filled in the channel for optical waveguide or is disposed on the substrate; wherein the refractive index in a part of the material varies substantially periodically or is substantially continuously monotone increasing or decreasing in the direction of light propagation.

Optical element and method of fabrication thereof

The invention provides a radio circuit realizing a desired receiving characteristic even when a strong-level interfering wave is received and operating with small power when no interfering wave is received. The radio circuit comprises a receiving circuit for selecting a signal having a desired frequency from received signals and demodulating the signal, an input-power detector for detecting power P of the receiving circuit, a received-power detector for detecting power P of a signal selected by the receiving circuit, and a reception control circuit for controlling the receiving circuit. The reception control circuit controls the receiving circuit at a low distortion by increasing the power consumption of a circuit included in the receiving circuit and thereby expanding the linear operation range when the power P detected by the input-power detector is larger than a predetermined value t and the power P detected by the input-power detector is smaller than a predetermined value t

Radio circuit and control method of radio circuit

Plural subcarrier-multiplexed AM signals are input and narrow-band-FM-modulated by a voltage controlled oscillator including the fundamental carrier wave and higher-order harmonics as the output, and the FM carrier wave component of the higher-order harmonics of the fundamental carrier wave is selectively taken out by a band-rejection filter shifted to the lower frequency side by a frequency converter converted into an optical signal by an electric/optic converter and transmitted.

Voltage controlled oscillator, FM signal optical transmitter, FM signal optical receiver and FM signal optical transmission system

FM signal converter, FM signal optical transmitter and FM signal optical receiver

The apparatus has: a wavelength tunable filter ; a photoelectric conversion part which converts transmitted light received from the wavelength tunable filter into a received light intensity signal; a received light intensity detecting part which detects the intensity of the received light intensity signal; a signal component detecting part which detects a signal component from the received light intensity signal; a signal intensity detecting part which detects the intensity of the signal component; an intensity variation detecting part which detects an intensity variation in the received light intensity signal which is detected and an intensity variation in the signal component; and a peak position detecting part and a wavelength scanning part which scan and a wavelength to be selected by the wavelength tunable filter based on the two detected variations.

Wavelength tunable filter apparatus

A semiconductor device package having a heat radiating base that has a depression. A circuit substrate is disposed on the heat radiating base to cover at least the depression. At least two semiconductor devices are mounted on both sides of the circuit substrates. The semiconductor device mounted on one major surface of the circuit substrate is coupled to the heat radiating base and is disposed in the depression.

Semiconductor device package for optical communication device

A narrow-band FM modulator provided with an optical transmitter converts a carrier signal having high carrier frequency higher enough than those of a plurality of signals into a narrow-band FM signal by FM-modulating the carrier signal with a small modulation index for substantially generating only a first sideband in accordance with a multiplexed signal generated by subcarrier-multiplexing the signals and a frequency converter converts a narrow-band FM signal into a low-frequency-converted narrow-band FM signal having a frequency lower enough than the carrier frequency. A semiconductor laser converts an optical signal into an FM optical signal by modulating the optical signal in accordance with a low-frequency-converted narrow-band FM signal and transmits the FM optical signal to an optical receiver through an optical-fiber cable

FM signal optical transmission apparatus and FM signal optical reception apparatus

Optical waveguide part, its manufacturing method, connection member, optical part, method for connecting optical waveguide part, and optical element

A wavelength tunable filter device has at least two optical fibers through which an optical signal is input or output; a wavelength selective element which the optical signal is input to and output from through a lens and which selects a wavelength; a mounting jig to which the wavelength selective element is fixedly secured; a rotating mechanism, having an ultrasonic motor and an encoder, for rotating the wavelength selective element; and a motor controller for controlling the ultrasonic motor for driving, wherein the mounting jig is rigidly mounted directly to a rotating shaft of the ultrasonic motor, and the amount of power that does not exceed the driving power necessary to cause the ultrasonic motor to start rotating from a stopped condition is intermittently applied to the motor controller.

Wavelength tunable filter device

In a package mounting an optical semiconductor module, an optical semiconductor module is supported by a supporter fixed on a metallic base such that the optical semiconductor module is inclined relative to the circuit board. Further, a lead pin of the optical semiconductor module is set as high as a signal input/output line of a high frequency circuit board. The lead pin is fixed at the shortest distance to the signal input/output line with solder. Thus, the performance of the optical semiconductor module is not deteriorated, and the other components on the circuit board are not affected. A circuit board may be arranged below the optical semiconductor module.

Growing community of inventors

Katano, Japan

Masanori Iida