Nec Corporation

Nippon Electric Co., Ltd.

Hiroshi Shiba

Susumu Ohi

Kenji Okada

Osamu Kudoh

Kouichi Nishimura

Mitsuo Ueoka

Susumu Sato

Koichi Koga

Masahiko Nakamae

Goro Ueda

Takuya Katoh

Sei Saitoh

Hideo Tsunemitsu

Hiroaki Mikoshiba

Yasuhiro Miyahara

Kenji Kani

Shoji Eguchi

Sei Saito

Mitiaki Sakamoto

A bending vibration type sound transmitter includes a plurality of vibrating bodies that perform resonant vibration and two lids. The plurality of vibrating bodies is fastened between the two lids.

Bending vibration type sound transmitter

A low frequency oscillator includes a plurality of drum-shaped oscillators. Each of the drum-shaped oscillators is constructed so that a pair of disk-shaped flexural vibrators is attached on both open ends of a conductive cylinder so as to be arranged face to face. And a conductive elongated coupling member is fixed to adjacent the drum-shaped oscillators at a central portion thereof so as to electrically connect between adjacent the disk-shaped flexural vibrators and thereby coupling the drum-shaped oscillators along a central axis thereof.

Low frequency oscillator, the omni-directional type low frequency underwater acoustic transducer using the same and the cylindrical radiation type low frequency underwater acoustic transducer using the same

Disclosed is an underwater projector projecting a sound underwater. The underwater projector includes a first disk-type resonator unit, a second disk-type resonator unit, and a central space. The second disk-type resonator unit is installed so that a central axis corresponds with that of the first disk-type resonator unit. The central space is set up between the first disk-type resonator unit and the second disk-type resonator unit, and water can enter the central space.

Underwater sound projector and underwater sound projection method

The present invention achieves the wideband operation of a bolted Langevin-type echo sounder transducer by enabling low frequency operation with securing a sound pressure level above a certain level without changing the external dimensions of the echo sounder transducer. This is an echo sounder transducer includes a Langevin-type vibrator having a front mass and a rear mass, and a cylindrical active vibrator which is sandwiched between the front mass and rear mass, a bend vibrator constituted of a diaphragm arranged in an acoustic radiation surface section of the front mass of the Langevin-type vibrator, and a disc type active vibrator fixed to the diaphragm. This has such structure that a slit, communicating from an outer peripheral side face toward an axial center, is provided on the circumference in the side of the lower portion of the front mass of the Langevin-type vibrator toward the rear mass.

Echo sounder transducer

A transducer includes a Langevin type vibrator, a bending vibrator, and a ring-like member. The Langevin type vibrator has a construction in which a front mass, a cylindrical vibrator, and a rear mass are provided in tandem, and those elements are tightened by a bolt. The bending vibrator is provided apart from the front mass. The ring-like member is provided in outer peripheral portions of the front mass and the bending vibrator to couple the front mass and the bending vibrator to each other. The transducer generates a large sound pressure over a wide frequency band since a sound wave radiation surface is wide and its amplitude amount is large.

Transducer with coupled vibrators

A plasma display panel is provided which is capable of suppressing the degradation of the fluorescent material layer by discharge and which ensures a long service life. The plasma display panel is obtained by assembling and airtight sealing of a first substrate provided with a plurality of surface discharge electrode pairs arranged so as to form a matrix with a second substrate provided with separating walls and fluorescent material layers disposed so as to conform with said plurality of surface discharge electrode pairs, wherein electrodes of one side of each electrode pair in said plurality of surface discharge electrode pairs are connected to each line bus wire among a plurality of line bus wires formed extending along the line direction on said first transparent insulating substrate, and the electrodes of the other side of each electrode pair in said plurality of surface discharge electrode pairs are connected to each row bus wire among a plurality of row bus wires disposed along the row direction on said first transparent insulating substrate formed extending along the row direction on said first transparent insulating substrate.

Plasma display panel and method for manufacturing the same

An active matrix liquid crystal display is provided, wherein adjacent two odd and even pixels are commonly connected to a single signal line, and two scanning lines are allocated to one horizontal display line, two switching elements of the adjacent two odd and even pixels are respectively connected to different ones of the two scanning lines and further the odd and even display lines are opposite to each other in connections of the display lines and the switching elements.

Active matrix liquid crystal display

In a liquid crystal display apparatus, the gamma characteristics of an image signal is changed each two frames, so that a driving voltage obtained from the changed gamma characteristics is applied to a liquid crystal. A wide viewing field angle can electrically be realized.

Liquid crystal display apparatus having an increased viewing angle

The present invention provides a circuitry of a liquid crystal display, comprising a plurality of signal lines extending in a first direction, a plurality of scanning lines extending in a second direction vertical to the first direction, first and second enable lines separated from each other, each of the first and second enable lines comprising a plurality of first parts extending in the first direction and between the signals lines and a second part extending in the second direction to which the first parts are connected; a plurality of pairs of first and second pixel electrodes being positioned in adjacent two pixels and also positioned at opposite sides of each of the signal lines; a series connection of first and second transistors between each of the first and second pixel electrodes and the signal line, the first transistor having a gate connected to each of the first and second enable lines while the second transistor having a gate connected to the scanning line.

A gamma correcting circuit has a plurality of differential amplifiers having respective input terminals for being supplied with a video signal and respective output terminals connected in common. At least one of the differential amplifiers comprises differential pairs of transistors including transistors whose bases are not connected to the input terminal, emitters are connected to respective resistors, and collectors are connected in common. A plurality of individually energizable and de-energizable external reference voltage supplies are connected to the bases of the transistors whose bases are not connected to the input terminal.

Gamma correcting circuit

An improvement of the LCD driving semiconductor IC which supplies a plurality of source driving voltages (corresponding to the horizontal scanning voltage of a CRT) to a plurality of source driving lines of an active matrix type LCD of TFT base is proposed. Each of sample/hold circuit that is provided in one-to-one correspondence to the source driving lines which carry out polarity inversion and extraction of voltage sample values of an image signal for every one line of horizontal scanning of applied voltages to liquid crystal cells for the purpose of preventing the deterioration of liquid crystal cells consisting of pixel display electrodes and counter electrodes of LCD and a liquid crystal material inserted between the electrodes, is composed of complementarily operating first circuit part and second circuit part, and the correspondence relation between polarity display pulse that controls the complementary operation of these circuit parts and the polarity of the voltage sample value, and these first/second circuit parts is fixed. By so doing, the variation range of the input voltage to each buffer amplifier of the first/second circuit parts was limited, the source-drain region formation process of the input transistor of its amplifier was simplified, and facilitated the improvement of the accuracy of the source driving voltage with respect to the input image signal.

Semiconductor device for driving liquid crystal display panel

An input terminal is connected to bases of first and second transistors. Collectors of the first and fourth transistors are connected to a power-source terminal. Collectors of the second and third transistors are grounded. A base of the third transistor is connected to an emitter of the first transistor. A base of the fourth transistor is connected to an emitter of the second transistor. One terminal of the capacitor is grounded and the other terminal thereof is connected to emitters of the third and fourth transistors and an input of an output buffer whose output is connected to an output terminal. A collector of a fifth transistor is connected to the power-source terminal and a base thereof is connected to the output terminal. A collector of a sixth transistor is grounded and a base thereof is connected to the output terminal. A first constant-current source is connected to an emitter of the fifth transistor and a base of the fourth transistor. A second constant-current source is connected to an emitter of the sixth transistor and the base of the third transistor. A third constant-current source is connected to the emitter of the first transistor and turned on at a sampling time. A fourth constant-current source is connected to the emitter of the second transistor and turned on at the sampling time.

Sample-and-hold circuit

A semiconductor device that has a feature in the spatial relationship between the wiring in a multi-level wiring and the intermediate insulating films. In the lower part of the second and/or subsequent levels of wiring there exist intermediate insulating films that have a pattern which is the same as the pattern of the wiring. Because of this arrangement, the intermediate insulating film does not exist between the wiring on the same level. The first structure of the multi-level wiring has the intermediate insulating films formed in wall-like shape, with the lower end of the intermediate insulating films reaching an underlying insulating layer formed on the surface of the semiconductor substrate. The second structure of the multi-level wiring is a quasi air gap metallization structure. As a result of realization of such structures, in the semiconductor device according to the present invention, the parasitic capacitance due to the coupling capacitances between the wiring can be reduced compared with a semiconductor device that has a structure in which the spaces between the wiring are filled with the intermediate films.

Growing community of inventors

Tokyo, Japan

Hiroshi Shiba