Matsushita Electric Industrial Co., Ltd.

Akira Enokihara

Kentaro Setsune

Toshiaki Nakamura

Hidetaka Higashino

Michio Okajima

Yasunao Okazaki

Koichi Mizuno

Minoru Tachibana

Hiroyuki Furuya

Kunihiko Minami

Mitsuo Makimoto

Morikazu Sagawa

Kiyotaka Wasa

Shigemi Kohiki

Shinichiro Hatta

Hideki Namba

Toshio Ishizaki

Toru Yamada

Hideaki Adachi

Takehiko Yamakawa

Masahiro Sakai

Takeshi Kamada

Shigenori Hayashi

Hiroyoshi Yajima

Yo Ichikawa

Masahiro Kosaki

Tomoaki Matsushima

An optical signal to electrical signal converter of the present invention comprises an optical waveguide propagating a modulated optical signal therethrough; a pair of electrodes disposed at positions opposite to each other sandwiching the optical waveguide with in a region where an electric field reaches that is generated in the optical waveguide when the optical signal propagates through the optical waveguide; and a resonator coupled to the pair of electrodes, the resonator receiving for excitation an electrical signal induced at the pair of electrodes by the electric field.

Optical signal-electric signal converter

An optical waveguide device has: photonic crystal regions, each having holesarranged in a periodic array; and an optical waveguide. Within the waveguide, high refractive index portionsare arranged along the waveguiding direction. Each of the high refractive index portionsis generally interposed between a pair of holeswhich are in symmetric positions with respect to the center axis. The center of gravity of every high refractive index portionis shifted along the waveguiding direction from a midpoint of a line interconnecting centers of the pair of holes, and is located between a position which is 0.45 r away from the midpoint in the waveguiding direction and a position which is 0.25 r away from the midpoint in the opposite direction, where r is a radius of each hole

Optical waveguide device

A photonic crystal device according to the present invention includes: a substrate; a periodic structure portionformed in or on the substrate, the periodic structure portionhaving a plurality of holesandarranged in a periodic array; at least one optical waveguideformed in or on the substrate, the at least one optical waveguidebeing adjacent to the periodic structure portion; and at least one optical resonatorformed in or on the substrate, the at least one optical resonatorbeing formed in a position away from the optical waveguide, with at least one holeamong the plurality of holesandof the periodic structure portionbeing interposed between the optical resonatorand the optical waveguide. The plurality of holesandof the periodic structure portioninclude a holehaving a depth different from a depth of the at least one holeinterposed between the optical waveguide andthe optical resonator

Photonic crystal device

An RF circuit component according to the present invention includes a substrate with a principal surface and a plurality of resonators, including a first resonator, a second resonator and a third resonator, which are arranged on the principal surface of the substrate so as to be coupled in series together. Each of the first, second and third resonators is made of a conductor supported on the substrate. The resonant modes of each of the first, second and third resonators include two fundamental resonant modes that oscillate perpendicularly to each other within a plane that is defined parallel to the principal surface of the substrate. The second resonator is arranged between the first and third resonators, and the oscillation direction of one of the fundamental resonant modes of the second resonator defines an angle greater than 0 degrees but smaller than 90 degrees with respect to that of its associated fundamental resonant mode of the first resonator and/or the third resonator.

RF circuit component

A dielectric filter is provided with a dielectric multilayer structure formed by layering two or more dielectric layers which have different relative permittivities, at least one feeding electrode formed between any dielectric layers or formed inside of any dielectric layers of the dielectric multilayer structure, and a shield portion that covers the outer surface of the dielectric multilayer structure and is made of a conductive material placed so as to fit on the outer surface without any gap.

Dielectric filter

A high-frequency circuit device includes a dielectric member, a shielding conductorsurrounding the dielectric member, a support memberfor fixing and supporting the dielectric member, and a pair of transmission lineseach of which is formed of a microstrip-line. Each of the transmission lines includes a substrateformed of a dielectric material, a strip conductor, and an earth conductor layer. An end portion of the strip conductorfaces part of the dielectric memberand functions as a coupling probe for input/output coupling. Each of the transmission linesis formed of a strip line, a mictostrip line, a coplanar line or the like, and has low-loss when connected to a circuit board.

High-frequency circuit device and high-frequency circuit module

The resonator of the present invention includes a cylindrical dielectric and a conductor film covering the surface of the dielectric in close contact therewith. The conductor film is constructed of a cylindrical portion and two flat portions, and is formed by subjecting the surface of the dielectric to metallization or the like. With the conductor film formed in close contact with the dielectric, deterioration of the Q value and the like caused by instability of connection at the corners can be suppressed even when a radio frequency induced current flows from the cylindrical portion over the two flat portions.

Resonator and high-frequency filter

A dielectric resonator filter comprises dielectric resonators, an enclosure having a main body, a lid, and partition walls, interstage-coupling tuning windows, interstage-coupling tuning bolts, input/output terminals, and input/output coupling probes. Resonance-frequency tuning members each composed of a conductor plate and a bolt coupled integrally thereto are attached to the enclosure lid. Undesired-mode suppressing means such as rings attached to the bolts of the resonance-frequency tuning members or bolts attached to the conductor plates or to the enclosure lid are disposed in an undesired-mode excitation space, whereby the occurrence of a disturbed characteristic in the pass band (or stop band) is suppressed.

Dielectric resonator filter

An optical modulator includes an optical waveguide, a modulating electrode, a conductive layer, an electric signal input section, and connector members. At least a portion of the optical waveguide is made of an electro-optic material. The modulating electrode includes a first conductor line and a second conductor line, which are coupled together electromagnetically, and applies a modulating electric field to a portion of the optical waveguide. The conductive layer forms a first microstrip line with the first conductor line and a second microstrip line with the second conductor line, respectively. Through the electric signal input section, an RF modulating signal is supplied to the modulating electrode. The connector members connect the first and second conductor lines together at both ends. In this optical modulator, the first and second conductor lines function as an odd-mode resonator for the RF modulating signal.

Optical modulator and communications system including the optical modulator

A high-frequency circuit element including a substrate, a high-frequency circuit formed on the substrate, a metal box electromagnetically shielding the high-frequency circuit by enclosing the substrate and an input/output terminal placed on the metal box and inputting/outputting a high-frequency signal to/from the high-frequency circuit. Adding at least one plate for interrupting unwanted higher-order mode cutting off the propagation path of the high frequency waves in the space inside the metal box by substantially dividing the space inside the metal box makes it possible to cut off the propagation path where the high frequency waves propagates in the space inside the box and to suppress excitation and propagation of the unwanted higher-order mode that adversely affects the frequency characteristic of the high frequency circuit element.

High-frequency circuit element having means for interrupting higher order modes

In order to prevent filter characteristics from being deteriorated due to generation of a spurious pulse is unnecessary resonance at a high level in a passing band at the frequency in a microwave region used in a portable telephone system or the like, at least two types of dielectric resonators having different frequency characteristics in unnecessary harmonic modes except for a main mode near the passing band of a filter are arranged in spaces partitioned by partition walls in a shielding unit constituted by a metal case and a lid, so that a dielectric filter which can obtain preferable spurious suppressing characteristics.

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Nara, Japan

Akira Enokihara