Patents Assigned to Nippon Telegraph and Telephone Public Corporation
-
Patent number: 4799257Abstract: A wireless transmitter for PM (phase modulation) signal with a spectrum scrambler for relocation of input spectrum for privacy purposes is comprised of a differential circuit coupled with an input terminal, a spectrum scrambler coupled with output of said differential circuit, and FM (frequency modulation) modulator coupled with output of the spectrum scrambler. Due to the position of the differential circuit before the spectrum scrambler, modulation index of modulated PM signal and/or the frequency band of the modulated PM signal does not increase irrespective of spectrum scrambling.Type: GrantFiled: November 5, 1987Date of Patent: January 17, 1989Assignee: Nippon Telegraph & Telephone Public CorporationInventors: Masahichi Kishi, Seizo Seki, Noboru Kanmuri
-
Patent number: 4797143Abstract: An improved process for the production of optical fiber porous preforms of predetermined refractive index distribution by the vapor-phase deposition method is disclosed wherein a glass material and a dopant material are subjected to flame oxidation by the use of an oxyhydrogen burner to form fine glass particles which are deposited on one end of a supporting rod adapted to move apart from the oxyhydrogen burner while rotating to allow a rod-like porous preform to grow thereon. The improved process is characterized in that the correlation between the shape of the deposition face and the refractive index distribution is previously determined mathematically, and on a basis of the correlation therebetween, a process variable such as the distance between the porous preform and the burner is adjusted to produce the desired shape of the deposition face whereby there can be obtained an optimum refractive index distribution.Type: GrantFiled: July 19, 1985Date of Patent: January 10, 1989Assignees: Nippon Telegraph & Telephone Public Corporation, Sumitomo Electric Industries, Ltd.Inventors: Kazunori Chida, Hiroshi Yokota, Michihisa Kyoto, Hisao Sato, Minoru Watanabe, Naoki Yoshioka
-
Patent number: 4791485Abstract: An inter-frame encoding/decoding equipment for television signals consists of inter-frame encoding equipment encoding a difference between television signals and the output of a frame memory and inter-frame decoding equipment which receives an encoded signal sent from the inter-frame encoding device via a transmission line, which decodes by adding the output of the frame memory to the encoded signal. The inter-frame encoding equipment is provided with a first operation circuit which operates the remainders obtained by dividing, by a predetermined value, the number of bits of logic "1" in the bit groups into which the output or the input of the frame memory is divided by a predetermined unit. The inter-frame decoding equipment is provided with a second operation circuit which operates the remainders obtained by dividing, by a predetermined value, the number of bits of logic "1" in the bit groups into which the output or the input of the frame memory is divided by a predetermined unit.Type: GrantFiled: December 19, 1986Date of Patent: December 13, 1988Assignees: Nippon Telegraph & Telephone Public Corporation, Fujitsu Limited, NEC CorporationInventors: Hideo Kuroda, Naoki Mukawa, Makoto Hiraoka, Kiichi Matsuda, Mitsuo Nishiwaki, Shuzo Tsugane
-
Patent number: 4786954Abstract: A semiconductor memory device has a semiconductor substrate of one conductivity type in which a plurality of memory cells are formed, each of the plurality of memory cells including at least one capacitor and having a trench which is formed from one major surface of the semiconductor substrate so as to surround at least one memory cell, wherein a first insulating film having element isolation properties is formed on a bottom and most areas of side wall surfaces of the trench, a first conductive film serving as one electrode of the capacitor is formed on the side wall of the first insulating film and an exposed portion of the semiconductor substrate which is not covered with the first insulating film, a second insulating film is formed on the first conductive film, and a second conductive film serving as the other electrode of the capacitor is formed on the second insulating film.Type: GrantFiled: October 19, 1987Date of Patent: November 22, 1988Assignee: Nippon Telegraph & Telephone Public CorporationInventors: Takashi Morie, Kazushige Minegishi, Shigeru Nakajima
-
Patent number: 4783664Abstract: A shaped offset-fed dual reflector antenna having a main reflector, a sub-reflector and a primary radiator which do not block the wave-path of said main reflector is improved by using an inclined primary radiator from a boresight axis of the antenna, and the shaped non-quadratic surface in said main reflector and/or said sub-reflector, to provide the desired aperture field distribution, improved cross-polarization characteristics, and improved side-lobe characteristics. The incline angle of the primary radiator is in the range between 10 degrees and 40 degrees. When a gregorian antenna is used, and the aperture field distribution is Tailor's -40 dB distribution, said incline angle is preferably 16 degrees.Type: GrantFiled: February 25, 1985Date of Patent: November 8, 1988Assignee: Nippon Telegraph & Telephone Public CorporationInventors: Masahiro Karikomi, Kenichi Kagoshima
-
Patent number: 4766313Abstract: An apparatus for quantitative secondary ion mass spectrometry comprising a sealed chamber for storing a sample containing a light impurity element which is to be analyzed, secondary ion generating means for bombarding a primary ion beam onto the sample so as to allow the sample to emit a secondary ion of the light element, and quantitative analyzing means for detecting the secondary ion so as to quantitatively analyze the light element contained in the sample. First evacuating means evacuates said sealed chamber to an ultrahigh vacuum during quantitative analysis. First cryopanel means is arranged to surround the sample, and first cooling means keeps said first cryopanel means at a cryogenic temperature during quantitative analysis so that said first cryopanel means adsorbs a gas present in said sealed chamber.Type: GrantFiled: February 26, 1987Date of Patent: August 23, 1988Assignee: Nippon Telegraph & Telephone Public CorporationInventors: Yoshikazu Homma, Yoshikazu Ishii
-
Patent number: 4742558Abstract: According to an image information retrieval/display apparatus, an original image is represented by a hierarchical structure from a global image of high level to a local image of low level in accordance with resolutions thereof. Only difference information between the images of the respective levels is coded and stored, so that the number of codes will not be increased. When an operator directly designates any partial area within the displayed global image, local images are sequentially retrieved. By adding and combining the difference information of the retrieved local image in the designated area within the global image, the desired local image can be displayed at high speed.Type: GrantFiled: February 7, 1985Date of Patent: May 3, 1988Assignee: Nippon Telegraph & Telephone Public CorporationInventors: Satoshi Ishibashi, Kenji Ogura, Susumu Yonezawa
-
Patent number: 4736461Abstract: A portable unit that may be called from a base station through a radio control channel by a succession of terminating call signals that is sent through the control channel from the base station to the portable unit for a first or restricted time duration (T.sub.1), selected in consideration of a battery saving period of a battery saving operation carried out in the portable unit. Within the battery saving period, the portable unit is put into transient active and inactive states during a first time interval and a second time interval, respectively. Selection is made so that the first time duration is longer than the second time interval to receive at least one of the terminating call signals within the first time duration in the portable unit. The base station monitors an acknowledgement signal for a second time duration (T.sub.2) after the lapse of the first time duration and interrupts the control channel when the acknowledgement signal is not received within the first and the second time durations.Type: GrantFiled: February 12, 1987Date of Patent: April 5, 1988Assignees: Nippon Telegraph & Telephone Public Corporation, NEC Corporation, Kabushiki Kaisha ToshibaInventors: Ryoji Kawasaki, Kazuhiro Yoshizawa, Akio Yotsutani, Noboru Saegusa, Koichi Ito, Syozi Huse
-
Patent number: 4726064Abstract: A wireless receiver for a PM (phase modulation) signal with a spectrum scrambling for relocation of speech spectrums for the privacy of purpose is comprised of an antenna for receiving PM modulated signals, an FM demodulator coupled with the antenna, a spectrum de-scrambler connected to output of the FM demodulator, an integration circuit connected to output of said spectrum de-scrambler, and an output terminal coupled with output of the integration circuit. Due to the location of the de-scrambler between the FM demodulator and the integration circuit, a noise spectrum of a reception signal is independent from a design of spectrum scrambling, and an excellent substantial S/N is obtained irrespective of spectrum scrambling.Type: GrantFiled: October 1, 1984Date of Patent: February 16, 1988Assignee: Nippon Telegraph & Telephone Public CorporationInventors: Masahichi Kishi, Seizo Seki, Noboru Kanmuri
-
Patent number: 4722584Abstract: An optical connector ferrule and a method for producing such an optical connector ferrule wherein the bonding between a metal sleeve and the main body of the ferrule, which is made of a synthetic resin material, is markedly improved. A rearward end of the metal sleeve is embedded in the synthetic resin material, preferably, around a flange of the main body. The metal sleeve may be provided with irregularities on one or both of the inner and outer surfaces thereof to further improve the adhesion between the resin of the main body and the metal sleeve.Type: GrantFiled: March 22, 1985Date of Patent: February 2, 1988Assignees: Sumitomo Electric Industries Ltd., Nippon Telegraph & Telephone Public CorporationInventors: Toshiaki Kakii, Koichiro Matsuno, Norio Kashima
-
Patent number: 4720734Abstract: A diode having a Schottky barrier which permits bidirectional passage of minority carriers as well as majority carriers through the provision of a bidirectional conducting Schottky electrode that substitutes for the conventional Schottky electrode used in Schottky diodes or for the low-high electrode in Pn junction diodes.Type: GrantFiled: December 1, 1986Date of Patent: January 19, 1988Assignee: Nippon Telegraph and Telephone Public CorporationInventors: Yoshihito Amemiya, Yoshihiko Mizushima
-
Patent number: 4703998Abstract: A water-tight optical fiber cable constructed without the need of a viscous water-blocking compound. At least one water-absorbing fibrous braid is placed adjacent each optical fiber to absorb any water which may be present in or enter the cable. Additionally, one or more water-absorbing fibrous braids may be disposed between a tape layer and the surrounding protective sheath of the cable.Type: GrantFiled: March 5, 1985Date of Patent: November 3, 1987Assignees: Sumitomo Electric Industries, Ltd, Nippon Telegraph & Telephone Public CorporationInventors: Fumikiyo Uchioke, Ichiro Ogasawara, Shuzo Suzuki
-
Patent number: 4688955Abstract: A serial printer having a platen (5) and a carriage (4) having a printer head (6) with a plurality of aligned print needles close to the platen (5) for mosaic printing is disclosed. According to the present invention, an ink ribbon is in a detachable ribbon cartridge (3) under tension, and the printer head (6) has a smooth slope at the top of the head (5) that slopes towards the platen, thus, when the ribbon cartridge is put on the printer, the ink ribbon is temporarily twisted at the top of the slope on the head (6), and by swinging the printer head (5) a few times along the platen (6), the ink ribbon (1) at the top of the slope slides down along the slope into the narrow gap between the head (6) and the platen (6), and thus, the ink ribbon (1) is positioned in front of the print needles.Type: GrantFiled: September 14, 1982Date of Patent: August 25, 1987Assignees: Oki Electric Industry Co., Ltd., Nippon Telegraph & Telephone Public CorporationInventors: Minoru Isobe, Shuichi Imai, Toru Hiroki, Tadasi Kodama, Waturu Ohara
-
Patent number: 4686168Abstract: A resist material of positive type having a high sensitivity, a high resolving power and an excellent adhesion property to substrates, which comprises a copolymer of a fluoroalkyl acrylate having the general formula: ##STR1## wherein R.sub.1 is methyl group, ethyl group, a halogen-substituted methyl or ethyl group, a halogen atom or hydrogen atom, R.sub.2 is a bivalent hydrocarbon group having 1 to 6 carbon atoms, and R.sub.f is a fluoroalkyl group having 1 to 15 carbon atoms, with an acrylic comonomer selected from the group consisting of a glycidyl acrylate, an acrylic acid, an acrylamide and an .alpha.-cyanoacrylate.Type: GrantFiled: March 11, 1985Date of Patent: August 11, 1987Assignees: Daikin Kogyo Co., Ltd., Nippon Telegraph & Telephone Public CorporationInventors: Tsuneo Fujii, Hiroshi Inukai, Takayuki Deguchi, Toshihiko Amano, Masami Kakuchi, Hiroshi Asakawa, Osamu Kogure
-
Patent number: 4684213Abstract: A submarine optical fiber cable includes inner and outer dams at suitable intervals for limiting water flow in the cable. The outer dams are formed in a space between inner and outer metal tubes of a pressure resisting sheath of the cable, and the inner dams are formed in the inner tube in which an optical fiber unit is enclosed. Each dam is made of a sticky compound or a jelly of plastics resin which is loaded at the dam position. The cable is also provided with a scale which represents distance from one end of the cable.Type: GrantFiled: May 14, 1984Date of Patent: August 4, 1987Assignees: Nippon Telegraph & Telephone Public Corporation, Ocean Cable Co., Ltd.Inventors: Koushi Ishihara, Yasuji Murakami, Nobuyuki Yoshizawa, Kiyoshi Funaki
-
Patent number: 4679899Abstract: An optical fiber of a silica-based material includes a coating of cured silicone rubber covering an outer surface thereof. The cured silicone rubber coating, when subjected to an infrared spectroscopic measurement, has a transmissivity of not less than 70% at a wave number of 2100 to 2200 cm.sup.-1 at a coating thickness of 0.1 mm due to the infrared absorption due to the stretching and vibration of SiH. The coating of cured silicone rubber contains a neglibible amount of SiH so that the transmission loss of the optical fiber can be prevented from increasing over a long period of time.Type: GrantFiled: February 28, 1985Date of Patent: July 14, 1987Assignees: Fujikura Ltd., Nippon Telegraph & Telephone Public CorporationInventors: Toshiaki Kobayashi, Kazuo Sanada, Toshiaki Murayama, Yasuyuki Sugawara, Naoshi Uesugi
-
Patent number: 4679244Abstract: A portable unit that may be called from a base station through a radio control channel by a succession of terminating call signals that is sent through the control channel from the base station to the portable unit for a first or restricted time duration (T.sub.1), selected in consideration of a battery saving period of a battery saving operation carried out in the portable unit. Within the battery saving period, the portable unit is put into transient active and inactive states during a first time interval and a second time interval, respectively. Selection is made so that the first time duration is longer than the second time interval to receive at least one of the terminating call signals within the first time duration in the portable unit. The base station monitors an acknowledgement signal for a second time duration (T.sub.2) after the lapse of the first time duration and interrupts the control channel when the acknowledgement signal is not received within the first and the second time durations.Type: GrantFiled: February 26, 1985Date of Patent: July 7, 1987Assignees: Nippon Telegraph & Telephone Public Corporation, NEC Corporation, Kabushiki Kaisha ToshibaInventors: Ryoji Kawasaki, Kazuhiro Yoshizawa, Akio Yotsutani, Noboru Saegusa, Koichi Ito, Syozi Huse
-
Patent number: 4668949Abstract: In a pager receiver (12) of a paging system, a reception controller (21) is kept operable when a switch (22) is closed. A first transistor (31) energizes a receiver part (16, 17) at the beginning of a call code part of a received calling signal. If a calling code for that receiver is detected at a certain call time slot of the call code part, the first transistor keeps the energization until the end of that call code part and again energizes the receiver part during a message time slot corresponding to that call time slot in a message code part which next follows that call code part in the received calling signal. A second transistor (32) energizes a display part (26-28) a little before that message time slot. If a message code is detected at that message time slot, the second transistor keeps the energization to generate an alert tone and a visual display. As soon as a blank message pattern is detected at that message time slot, the second transistor suspends the energization.Type: GrantFiled: February 26, 1986Date of Patent: May 26, 1987Assignees: Nippon Electric Co., Ltd., Nippon Telegraph & Telephone Public CorporationInventors: Masaaki Akahori, Hiroshi Watanabe
-
Patent number: 4665423Abstract: This invention concerns a voltage control type variable resistor using a metal oxide semiconductor (MOS) and other metal insulated semiconductors (MIS) wherein an offset gate MIS transistor having smaller threshold voltage and a self-aligned gate MIS transistor having a larger threshold voltage than that of said offset gate MIS transistor in absolute value are formed in parallel on one insulated substrate. The sources, the drains and the gates of both transistors are connected in common. A voltage control type MIS variable resistor described above, can be improved to have a wider linear range of resistance and voltage.Type: GrantFiled: October 2, 1985Date of Patent: May 12, 1987Assignee: Nippon Telegraph and Telephone Public CorporationInventor: Masahiro Akiya
-
Patent number: 4659215Abstract: A test optical fiber is slightly bent to a restorable extent, and light is side-illuminated on the bent portion to couple an optical signal to the test fiber. The optical signal coupled to the fiber by this method, propagates through the optical fiber in both directions. If the bending point, which is the point of coupling, is provided near one end of the optical fiber, because the power of the optical signal output from the end is substantially one half of the power of an optical signal coupled at the bending point, the transmission loss of the optical fiber can be measured by comparing the optical power with the optical power of the signal reaching the other end of the fiber.Type: GrantFiled: November 19, 1984Date of Patent: April 21, 1987Assignee: Nippon Telegraph and Telephone Public CorporationInventors: Shin Sumida, Hisashi Murata, Yutaka Katsuyama