Kabushiki Kaisha Toshiba

Yoshiaki Terashima

Hiroyuki Kayano

Hiroyuki Fuke

Mutsuki Yamazaki

Fumihiko Aiga

Tatsunori Hashimoto

Nobuaki Yasuda

Katsutarou Ichihara

Akio Hori

Hisashi Yoshino

Riichi Katoh

Sumio Ikegawa

Masayuki Sagoi

Shuichi Komatsu

Hideki Ohkawa

Shinji Arai

Senji Shimanuki

Tadahiko Maeda

Tadao Miura

Riichi Kato

A superconductor filter comprises a plurality of resonance elements arranged between input-output lines formed on a substrate. Metal conductor sections serving to inhibit the spatial coupling between the adjacent resonance elements are arranged between prescribed resonance elements, and a prescribed resonance element is coupled with another resonance element by a coupling transmission line. It follows that each resonance element is coupled with another resonance element by the direct coupling via the coupling transmission line or by the spatial coupling via the space.

Superconductor filter

A band pass filter which is configured by a microstrip line, or a strip line is provided. The band pass filter has a first half wavelength resonator which resonates at a center frequency of a pass band, a second half wavelength resonator which resonates at the center frequency of the pass band, and a transmission line through which the first half wavelength resonator is wire-coupled to the second half wavelength resonator. A strong coupling can be stably realized without causing deviation of the resonance frequencies of resonators.

Band pass filter having resonators connected by off-set wire couplings

A filter circuit has a complex block and exciting portions. The complex block has: a first block end resonator; a first resonator that is coupled to the first block end resonator; a second resonator that is coupled to the first resonator; a third resonator that is coupled to the second resonator; a fourth resonator that is coupled to the third resonator; and a second block end resonator that is coupled to the fourth resonator. Couplings between the first block end resonator and the second block end resonator, between the first resonator and the fourth resonator, and between the second resonator and the third resonator are in phase. The complex block and the exciting portions are single-path-coupled.

Filter circuit

A high-frequency device comprises a dielectric substrate, a filter element which has a plurality of resonating elements made of a first superconductor film on the dielectric substrate, a dielectric plate which faces the dielectric substrate substantially in parallel with the substrate and covers the plurality of resonating elements, and a spacing adjusting member configured to control the spacing between the dielectric plate and the dielectric substrate. The high-frequency device enables the pass-band frequency of the filter to be adjusted with high accuracy without variations in the skirt characteristic or ripple characteristic.

High-frequency device

A band pass filter configured by a planar structure circuit, includes resonators of distribution constant circuit type, transmission line paths coupling the resonators and excitation lines arranged at input/output sides. The transmission line path is provided with line path portions coupling the resonators or the resonator and the excitation line. The line path portion have a length which is (1+2m)/4-fold (m: natural number) of a wavelength corresponding to a center frequency of the frequency band, and each coupling part between the resonators and the line portion has a length substantially determined as a &#xbc; wavelength.

Band pass filter

There is disclosed a half-wavelength (&#x3bb;/2) resonator which is constituted of a micro strip line or a strip line and in which line pattern portions are disposed symmetrically with respect to a reference line, connected to each other to form an L shape, and formed in an open loop shape so as to have open ends. For one pair of line pattern portions having the open ends, base portions connected to adjacent line pattern portions are disposed in the vicinity of the reference line, and the open ends are extended in opposite directions so that the ends are disposed apart from the reference line.

Resonator and filter

A high frequency filter having steep skirt characteristics using a sapphire R-plane substrate. The filter comprises a substrate having first and second faces. The first face is a sapphire R-plane. A grounded conductive layer is formed on the second face of the substrate. A pair of input/output terminals is formed on the first face. In embodiments, hairpin-shaped resonating portions are formed between the pair of input/output terminals. Each of the resonating portions has at least one long side. Each long side of the resonating portions makes an angle of &psgr; with <11-20> direction of a sapphire substrate. The angle &psgr; satisfies relations 0&deg;&lE;&psgr;&lE;30&deg;. In embodiments, the resonating portions are asymetric, J-shaped, or rectangular with an opening.

High frequency super conductive filter

There is disclosed a planar filter which can variably control a pass frequency band with a high precision and which is superior in skirt property and little in ripple. A planar filter member and tuning member are disposed opposite to each other via a predetermined gap. The filter member is structured in such a manner that an input/output portion formed of a superconductor and a plurality of resonance elements are formed on a substrate. The tuning member is structured in such a manner that on the surface of a magnetic plate with a permeability changing by an applied magnetic field, a plurality of dielectric thin films, and a plurality of electrodes for applying electric fields to the dielectric thin films are arranged. Each of the dielectric thin films is disposed in a position opposite to a gap between the resonance elements of the filter member, or a gap between the filter member and the input/output portion. By applying a voltage between the electrodes, an effective permittivity &isin; of the gap between the resonance elements, or the gap between the resonance element and the input/output portion is variably controlled, and the skirt property and ripple are adjusted. Moreover, a resonance frequency of the resonance elements, a coupling between the resonance elements, and a coupling between the resonance element and the input/output portion may be individually and independently controlled.

Planar filter and filter system using a magnetic tuning member to provide permittivity adjustment

A superconductor filter includes a superconductor receiver filter of a planar transmission line structure including a signal input line, a resonator element and a signal output line and configured to select a signal received from an antenna, a superconductor transmitter filter of a planar transmission line structure including a signal input line, a resonator element and a signal output line and configured to select a signal transmitted to the antenna, the transmitter filter being arranged non-parallel to the receiver filter, and a heat-insulating container housing the superconductor receiver filter and the superconductor transmitter filter.

Superconductor filter and radio transmitter-receiver

A first electrically conductive layer whose thickness is equal to or smaller than the skin depth of the radio wave used for communication, a dielectric layer whose permittivity is changed by application of electric field, and a second electrically conductive layer whose thickness is equal to or smaller than the skin depth of the radio wave used for communication are sequentially stacked near a resonance element which is formed on the front surface of a dielectric substrate having a ground layer formed on the rear surface thereof. The effective permittivity of the dielectric layer is changed in a wide range by changing a voltage applied between the first and second electrically conductive layers to change the electric field applied to the dielectric layer. As a result, the impedance of the resonance element is changed, and when a plurality of resonance elements are arranged closely to each other to construct a filter, the coupling degree between the resonance elements is changed. Therefore, characteristics such as the resonance frequency of the resonator and the pass-band frequency of the filter are controlled by controlling a voltage to be applied.

Tunable resonance device controlled by separate permittivity adjusting

A method is disclosed which comprises setting a substrate within a mixed gas atmosphere containing 0.1 to 5% of oxygen gas and a balance as an inert gas, and sputtering a target member containing Ln, M, Cu and O within that atmosphere to obtain an oxygen-deficient perovskite type oxide superconducting thin-film of substantially Ln:M:Cu:O=1:2:3:(7-.delta.), where Ln represents at least one element selected from the rare earth elements and M represents at least one element selected from the group consisting of Ba, Sr, and Ca. The oxide superconducting thin-film of that composition ratio has a critical temperature of over 77K.

Method for manufacturing an oxide superconducting thin-film

In a reversible memory system, a pulsed laser beam generated from a laser unit is directed to a recording layer formed on a substrate 1. The recording layer essentially consists of a recording medium, for example, an iron-nickel alloy containing iron as a major component and 27 to 30 atomic % of nickel, which undergoes martensite transformation from a low-temperature phase to a high-temperature phase at a predetermined temperature Af and which undergoes a stress-induced transformation at a characteristic temperature Md. When a region of the recording layer is irradiated with the laser beam having a predetermined intensity, the region undergoes a stress-induced transformation so that the region is changed from the high temperature phase to the low temperature phase.

Reversible memory structure for optical reading and writing and which is

According to a disk-shaped magneto-optical recording medium of the invention, a transparent thin film serving as an interference layer is formed on a transparent substrate. The thin film is subjected to a plasma surface treatment, thereby decreasing the fused oxygen content in at least a surface portion thereof. A recording layer of a rare-earth-transition metal amorphous ferrimagnetic alloy thin film is formed on the plasma surface-treated film. Since the content of active, fused oxygen contained in at least the surface portion of the film decreases, rare-earth element oxide can hardly be formed in a boundary region between the recording layer and the transparent thin film. The content of the rare-earth element in this region is smaller than the average content in the overall recording layer.

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Yokosuka, Japan

Yoshiaki Terashima