Hitachi, Ltd.

Motohisa Nishihara

Satoshi Shimada

Kazuji Yamada

Kanji Kawakami

Hideo Sato

Yasumasa Matsuda

Seikou Suzuki

Minoru Takahashi

Tetsuo Ito

Seiko Suzuki

Masanori Tanabe

Yoshitaka Matsuoka

Shigeyuki Kobori

Masahiro Iwamura

Ikuro Masuda

Akio Yasukawa

Hiroaki Hachino

Ko Soeno

Hitoshi Minorikawa

Masatoshi Tsuchiya

Takeo Nagata

Mitsuo Ai

Katsuya Katohgi

Yukio Takahashi

Akira Tanaka

Takahiro Yamada

Yutaka Nishimura

Shigeru Azuhata

Ryoichi Kobayashi

Yoshishige Ohyama

Kaoru Uchiyama

Tadahiko Miyoshi

Yoshio Sato

Noboru Baba

Yutaka Misawa

Masaharu Tadauchi

Kazuyuki Ito

Hiromi Kagohara

Syoji Sagae

Tsutomu Okayama

Michitaka Shimazoe

Yusaku Nakagawa

Takahiko Tanigami

Tomio Yasuda

Tetsuo Doi

Hideyuki Nemoto

Ichiro Inamura

Ryosaku Kanzawa

Taisaku Kohzuma

A control apparatus for a gas turbine having an air flow control valve for controlling the flow rate of combustion air in an air flow passage from a compressor to the gas turbine, includes an air velocity or flow sensor arranged in the vicinity of the air flow control valve. A control unit operates to control the opening of a fuel flow regulation valve and/or an air flow control valve on the basis of a signal from the air velocity or flow sensor, thereby to control the air fuel ratio in a combustion section of the gas turbine.

Control apparatus for and control method of gas turbine

A method for generating X-rays in an X-ray tube, comprises the steps of: rotating an X-ray target of a rotating anode, the X-ray target having a metal coated layer thereon; applying electron beams emitted from a cathode onto the metal coated layer of the X-ray target; and offsetting thermal deformation of the X-ray target due to the application of the electron beams by deformation of the X-ray target due to centrifugal force, thereby maintaining a position of the X-ray target in a direction of the application of the electron beams, at a room temperature of the X-ray target, thus generating the X-rays.

X-ray tube and method for generating X-rays in the X-ray tube

A novel composite circuit comprises a first bipolar transistor with a collector of a first conductivity type connected to a first potential, an emitter of the first conductivity type connected to an output, a second bipolar transistor with a collector of the first conductivity type connected to the output and an emitter of the first conductivity type connected to a second potential, a field effect transistor of a second conductivity type with a gate connected to an input, a source connected to a third potential and a drain connected to the base of the first bipolar transistor, a field effect transistor of the first conductivity type with a gate connected to the input, a drain connected to the base of the first bipolar transistor, and a source connected to the base of the second bipolar transistor, and a unidirectional element inserted between the output and the drain of the field effect transistor of the first conductivity type and having a direction of rectification opposite to that of the PN junction formed between the base and emitter of the first bipolar transistor.

Composite circuit of bipolar transistors and field effect transistors

An image sensor comprises a transparent substrate, an optical lens formed integrally in one major surface of the transparent substrate, and a photosensor provided on the side of the other major surface of the transparent substrate and having output electrodes, wherein light incident on the optical lens is focussed by the lens onto the photosensor through the transparent substrate.

Image sensor

A semiconductor pressure transducer including a measuring diaphragm of semiconductor material for sensing pressure supported by a support member of the same material. An oxide layer and a thin glass layer are interposed between the measuring diaphragm and the support member.

Semiconductor pressure transducer

A capacitive pressure sensor and its manufacturing method are disclosed. An amplifier is formed on the main surface of a first semiconductor substrate by a diffusion process, and its surface is covered with an insulating film. An electrode is vapor-deposited on the surface of the amplifier and electrically connected to the amplifier through a through hole formed in the insulating film. For forming a diaphragm, the surface of a second semiconductor substrate disposed facing the electrode to form a capacitor, which is opposite to the surface of the second semiconductor substrate facing the electrode, is partially etched away to form a depression. The first and second semiconductor substrates are anodically bonded to each other using a glass layer.

Capacitive pressure sensor

Four semiconductor strain gauges constitute a bridge circuit. This bridge circuit and a sensitivity temperature compensation circuit are connected in series, and a constant voltage is applied to the series circuit. The sensitivity temperature compensation circuit varies a voltage across the bridge circuit, depending upon temperatures. The constant voltage is divided to produce a predetermined voltage. The predetermined voltage is selected to be equal to the voltage of one output side node of the bridge circuit at the time when the semiconductor strain gauges are unstrained and at a predetermined temperature. The point of this voltage and the output side node are connected through a resistor so as to perform zero-point temperature compensation.

Pressure sensor employing semiconductor strain gauge

A semiconductor strain gauge is arranged as a bridge having four piezoresistive elements which each include a low impurity concentration diffused portion and a heavily-doped diffused portion. The resistance values of the two low impurity concentration diffused portions opposite each other in the bridge are greater than the resistance values of the other two lower impurity concentration portions. The resistances of the heavily-doped diffused portion are selected so that the resistance of the piezoresistive elements are equal. However, by virtue of the fact that the resistance temperature coefficient of the low impurity portions are greater than the resistance temperature coefficients of the high impurity portions, the overall resistance temperature coefficients of the bridge arms will be different. This permits the zero-point voltage of the bridge to always increase with an increase in temperature.

Semiconductor strain gauge

A semiconductor pressure detector apparatus has a strain--electric signal conversion bridge which is composed of four semiconductor strain gauges, and an amplifier which serves to hold at a predetermined value the sum of currents flowing through the bridge. The midpoints of two arms constituting the bridge are respectively connected to the noninverting inputs of two negative feedback amplifiers. Outputs from the two negative feedback amplifiers are applied to a differential amplifier, and an output proportional to the difference of the outputs of the former amplifiers appears at an output terminal of the latter amplifier. A potential equal to potentials which appear at the midpoints of the two arms of the bridge when the bridge is in its balanced state at a predetermined temperature and under a predetermined pressure is generated by two resistances which are connected in series with a supply voltage, and the potential is applied through a switch to either of the inverting inputs of the two negative feedback amplifiers, whereby the zero-point temperature compensation of this apparatus is made.

Semiconductor pressure detector apparatus with zero-point temperature

A semiconductor pressure sensor having plural pressure sensitive diaphragms and capable of producing electric signals of at least two pressures. A semiconductor pressure sensor has a semiconductor single crystal chip (1) on which two diaphragms (12a, 12b) are shaped, pairs of strain gauges (13a and 14a, and 13b and 14b), each of which pairs are constructed on each pressure sensitive diaphragm, electrodes (15a and 16a, and 15b and 16b) which are provided for electrical connections of these strain gauges on the semiconductor single crystal, and an insulating substrate of borosilicate glass, the thermal expansion coefficient is substantially equal tol that of said semiconductor single-crystal chip, wherein the semiconductor single-crystal chip (1) and the glass substrate (2) are bonded to each other by an Anodic Bonding method, thereby being able to obtain a semiconductor pressure sensor which scarcely producing errors outputs.

Semiconductor pressure sensor having plural pressure sensitive

A strain gauge is formed on one main surface of a semiconductor single crystal substrate while an insulating oxide film is formed on the other main surface of the substrate. A metal junction layer including several layers inclusive of eutectic alloy layers is formed on the surface of the insulating oxide film and the thus prepared structure is mounted on a metal strain generator. By heating this assembly to temperatures approximating to the eutectic point of the eutectic alloy layer, the semiconductor substrate and the metal strain generator are joined together.

Method of producing semiconductor displacement transducer

A semiconductor absolute pressure transducer assembly has a silicon diaphragm assembly and a covering member. The silicon diaphragm assembly has a circular pressure sensitive diaphragm, on the surface of which are diffused piezoresistors and conducting paths. The covering member composed of borosilicate glass has a circular well formed therein. On the surface of the silicon diaphragm assembly on which the piezoresistors and the conducting paths are diffused, a passivating layer of silicon dioxide is deposited. Further on the passivating layer, a conductive layer is formed by, for example, evaporating silicon. And the glass covering member is bonded on the silicon diaphragm assembly by anodic bonding. Namely, the silicon diaphragm assembly and the glass covering member are heated up to a certain high temperature and a relative high voltage applied across the conductive layer of the silicon diaphragm assembly and the glass covering members.

Semiconductor absolute pressure transducer assembly and method

A semiconductor substrate has a major surface, another major surface on the opposite side of the first major surface, a strain gauge stripe formed in the central portion of the second major surface by diffusing an impurity therein, and electrodes connected to the strain gauge stripes. These strain gauge stripes are spaced from the peripheral edge of the second major surface by a distance greater than 1/3 of the length of the same major surface. The first major surface of the semiconductor substrate is bonded to an elastic metal load plate.

Semiconductor strain gauge with elastic load plate

A semiconductor pressure transducer assembly comprising a silicon diaphragm assembly and a glass covering member. The silicon diaphragm assembly has a circular diaphragm portion of thin silicon which is formed using etching, and a thick supporting portion therearound. Piezoresistive elements of a piezoresistive bridge circuit and conducting paths for electrically connection thereof are formed on the silicon diaphragm assembly. On a surface of the silicon diaphragm assembly, a passivating layer of silicon dioxide are formed in uniform thickness, and further on a surface of the passivating layer is formed a layer of polysilicon on the supporting portion of the silicon diaphragm assembly. In the passivating layer, a contacting window is formed, through which the polysilicon layer is electrically connected to the silicon diaphragm assembly. The covering member of borosilicate glass having a circular well is mounted and bonded onto the silicon diaphragm assembly in contact with the polysilicon layer using Anodic Bonding method. And the processed silicon diaphragm assembly has a flat surface thereof, on which the piezoresistive elements and the conducting paths are constructed using Ion Implantation method, or reforming a silicon dioxide layer thereon after removing another silicon dioxide layer used as mask in diffusing process.

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Katsuta, Japan

Motohisa Nishihara