Patents by Inventor Shinichi Kawamura

Shinichi Kawamura has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6974654
    Abstract: An electrophotographic photoconductor has an electroconductive support and a photoconductive layer which is formed thereon and contains at least one resin of a polyurethane resin, a polyester resin, or a polycarbonate resin, each resin having at least a structural unit of formula (1): wherein R1, R2, R3, a, b, and n are the same as those specified in the specification. An electrophotographic image forming apparatus and method, and a process cartridge employ the above photoconductor.
    Type: Grant
    Filed: December 16, 2003
    Date of Patent: December 13, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinichi Kawamura, Kazukiyo Nagai, Tomoyuki Shimada, Chiaki Tanaka, Michihiko Namba
  • Publication number: 20050201561
    Abstract: According to embodiments of the present invention, in a case where a ground for security is laid in difficulty in executing an inverse function operation of a trapdoor one-way function, represented by an RSA problem, even when a signature order advances, an increase of a size of a key can be inhibited. For example, when the first partial data ?i-1,L exceeding (k0+k1) bits when concatenating a random number ri of k0 bits is excluded from an input of binary operation on an input side of a signature generation function. Accordingly, a size of an operation result si of the binary operation is set to be constant at (k0+k2) bits, and, as a result, an input size (key length k bits) of an RSA signature generation function is set to be constant.
    Type: Application
    Filed: January 19, 2005
    Publication date: September 15, 2005
    Inventors: Yuichi Komano, Kazuo Ohta, Shinichi Kawamura, Atsushi Shimbo
  • Patent number: 6939651
    Abstract: An electrophotographic photoconductor comprising at least an electroconductive support and a photoconductive layer which is formed on said electroconductive support, the outermost layer of the photoconductor contains particles comprising a polyorganosiloxane-containing phase which contains polyorganosiloxane and an organic polymer-containing phase which contains organic polymer without silicon and has a polyorganosiloxane content which is less than the polyorganosiloxane-containing phase, each phase being exposed at the top surface of the photoconductor.
    Type: Grant
    Filed: June 21, 2002
    Date of Patent: September 6, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Hongguo Li, Kazukiyo Nagai, Masaomi Sasaki, Shinichi Kawamura, Yasuo Suzuki, Nozomu Tamoto, Kawori Tanaka
  • Patent number: 6940975
    Abstract: A pair of a pattern of a mask and a mask pattern obtained by bit inversion of the mask is prepared for each round function in a data scrambler. Every time encryption is to be performed, one mask pattern of the pair is randomly selected by a switch, and an exclusive OR of an input to an S-box and the selected mask pattern is calculated. In addition, an exclusive OR of an output from the S-box and bits of inverse permutation of the mask is calculated. The exclusive ORs are calculated in advance and stored as a table in the S-box. Furthermore, an exclusive OR of the output from each round function and a mask is calculated and concealed. The influence of the mask is removed by calculating the exclusive OR with the mask again on the next round.
    Type: Grant
    Filed: August 19, 1999
    Date of Patent: September 6, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinichi Kawamura, Fumihiko Sano
  • Publication number: 20050157871
    Abstract: According to each embodiment of the present invention, random function operations less than three times and tight security can simultaneously be implemented. More specifically, a ciphertext y=c?t or a signature ?=c??t is created as concatenated data of two data. The concatenated data is created by using a public key encryption scheme for only one (necessary part s) of the data. For this reason, tight security for the one-way characteristic of a trapdoor one-way function of the public key encryption scheme can be implemented. In addition, the output size of a first random function H? is limited. Accordingly, a random function G for bit expansion in the conventional. OAEP++-ES scheme can be omitted. Hence, the number of times of use of random functions can be reduced to two.
    Type: Application
    Filed: August 2, 2004
    Publication date: July 21, 2005
    Inventors: Yuichi Komano, Shinichi Kawamura, Atsushi Shimbo
  • Patent number: 6919419
    Abstract: An aromatic block polycarbonate resin is prepared by polymerizing a diphenol compound of formula (2) or (4), a diol compound of formula (1) or (5), and a halogenated carbonyl compound. The diphenol compound of formula (4) is produced by polymerizing the diphenol compound of formula (2) and a halogenated carbonyl compound by solution or interfacial polymerization. An electrophotographic photoconductor has an electroconductive support and a photoconductive layer formed thereon containing the above-mentioned aromatic block polycarbonate resin. An electrophotographic image forming method or apparatus employs the above-mentioned photoconductor. A process cartridge holds therein the photoconductor and at least one of the electrophotographic image forming units.
    Type: Grant
    Filed: January 22, 2003
    Date of Patent: July 19, 2005
    Assignees: Ricoh Company Ltd., Hodogaya Chemical Co., Ltd.
    Inventors: Kohkoku Ri, Masaomi Sasaki, Kazukiyo Nagai, Shinichi Kawamura, Susumu Suzuka, Katsuhiro Morooka
  • Publication number: 20050140570
    Abstract: Gate electrode lines 11 formed on glass substrate 3 are separated by separating portions 32 for respective pixels 5 to shorten lengths of gate electrode lines 11. Both end portions of gate electrode lines 11 separated by separating portions 32 are electrically connected by conductive films 42 made from the same materials as signal electrode lines 13. When glass substrate 3 is lifted up while glass substrate 3 is charged with static electricity, the increases in voltages at gate insulation film 31 provided between gate electrode lines 11 and polycrystalline semiconductor film 22 are effectively suppressed so that electrostatic destruction of gate electrode lines 11 can be prevented.
    Type: Application
    Filed: October 21, 2004
    Publication date: June 30, 2005
    Applicant: Toshiba Matsushita Display Technology Co., Ltd.
    Inventors: Hiroshi Tabatake, Tetsuya Kawamura, Shinichi Kawamura, Katsuhiko Inada, Atsushi Takeda, Nobuo Imai, Akihiro Takami
  • Patent number: 6891950
    Abstract: There are disclosed an extended key generator, encryption/decryption unit, and storage medium, in which as each of key transform functions, a transform process is done by an S box (substitution table) on the basis of a first key obtained from the inputted key, and an adder computes a corresponding one of extended keys on the basis of a value obtained by shifting the transformed result of the S box to the left, and a second key obtained from the inputted key.
    Type: Grant
    Filed: August 31, 2000
    Date of Patent: May 10, 2005
    Assignees: Kabushiki Kaisha Toshiba, Matsushita Electric Industrial Co., Ltd.
    Inventors: Motoji Oomori, Kaoru Yokota, Tsutomu Sekibe, Makoto Tatebayashi, Fumihiko Sano, Shinichi Kawamura
  • Publication number: 20050084711
    Abstract: A 3,6-diphenylcarbazole compound, which has a specific formula and realizes an organic electroluminescent device having high durability and high luminous efficiency. An electroluminescent device which includes an anode; a cathode which faces the anode; and at least one layer including a luminescent layer, optionally a hole transporting layer and an electron transporting layer, which is located between the anode and the cathode, wherein the at least one layer includes the 3,6-diphenylcarbazole compound.
    Type: Application
    Filed: September 3, 2004
    Publication date: April 21, 2005
    Inventors: Masaomi Sasaki, Masafumi Torii, Toshiya Sagisaka, Takashi Okada, Shinichi Kawamura, Chihaya Adachi, Yuuichiroh Kawamura, Kenji Muneuchi
  • Patent number: 6869913
    Abstract: Novel pyridazin-3-one derivatives of formula [1] are provided, which are useful as active ingredients of herbicides, wherein R1 is haloalkyl; R2 and R3 are hydrogen, alkyl, haloalkyl, or alkoxyalkyl; and Q is [Q-1], [Q-2], [Q-3], [Q-4] or [Q-5]. Also provided are their use and intermediates for their production.
    Type: Grant
    Filed: February 9, 2004
    Date of Patent: March 22, 2005
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Tadashi Katayama, Shinichi Kawamura, Yuzuru Sanemitsu, Yoko Mine
  • Patent number: 6842523
    Abstract: In an encryption apparatus for encrypting a data body to contain an encrypted data body in transmission data and transmitting the transmission data to a receiver, the transmission data includes sender's key recovery data obtained by encrypting recovery information for recovering a key for decrypting the encrypted data body to allow a key recovery agent registered by a sender to decrypt the recovery information, and receiver's key recovery data obtained by encrypting the recovery information for recovering the key for decrypting the encrypted data body to allow a key recovery agent registered by a receiver to decrypt the recovery information.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: January 11, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akito Niwa, Shinichi Kawamura, Megumi Aoki, Toshiaki Saisho, Tatsuya Ishihara, Fumihiko Sano, Satomi Hori
  • Publication number: 20050003287
    Abstract: An electrophotographic photoconductor has an electroconductive support, and a photoconductive layer formed thereon containing as an effective component an aromatic polycarbonate resin having a structural unit of formula (2) and a structural unit with charge transporting properties, each of the structural units being contained in an amount of 5 wt. % or more of the total weight of the polycarbonate resin. There is disclosed an aromatic polycarbonate resin having a structural unit of formula (1) and the structural unit of formula (2), with the relationship between the composition ratios being 0<k/(k+j)<1 when the composition ratio of the structural unit (1) is k and that of the structural unit (2) is j, or an aromatic polycarbonate resin having a repeat unit of formula (3). The formulas (1) to (3) are specified in the specification.
    Type: Application
    Filed: July 1, 2004
    Publication date: January 6, 2005
    Applicant: RICOH COMPANY, LTD.
    Inventors: Shinichi Kawamura, Masaomi Sasaki, Kazukiyo Nagai, Kohkoku Ri, Susumu Suzuka, Katsuhiro Morooka
  • Publication number: 20040212042
    Abstract: An aryl amine polymer is provided which contains a specific repeat unit, its use in preparing an organic semiconductor material which contains the aryl amine polymer and an additional specific compound and in the preparation of organic light emitting devices (OLED), organic thin film transistors (TFT) and so on, along with an organic TFT including a substrate, an organic semiconductor layer which contains the organic semiconductor material and is located overlying the substrate, an electrode pair of a source electrode and a drain electrode; and a third electrode.
    Type: Application
    Filed: February 13, 2004
    Publication date: October 28, 2004
    Inventors: Toshiya Sagisaka, Masaomi Sasaki, Masafumi Torii, Shinichi Kawamura, Takashi Okada, Yoshinobu Nakayama, Yoshikazu Akiyama, Hitoshi Kondoh, Hidenori Tomono, Takumi Yamaga
  • Patent number: 6807555
    Abstract: In a modular arithmetic apparatus including a plurality of product-sum circuits having a modular arithmetic function and parallelly arranged, and a correction term calculation unit for calculating a correction term to be used for modular arithmetic operation in the product-sum circuits, the correction term calculation unit sequentially calculates the correction term in units of bits, and each of the product-sum circuits sequentially reflects the correction term calculated by the correction term calculation unit and performs base conversion or base extension.
    Type: Grant
    Filed: September 12, 2003
    Date of Patent: October 19, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Shinichi Kawamura
  • Publication number: 20040198027
    Abstract: A method of preparing a poly-crystalline silicon (p-Si) film is provided with efficient dehydrogenation treatment of an amorphous silicon (a-Si) film deposited by a plasma enhanced chemical deposition (PECVD) process. A substrate is received in a process chamber of a PECVD system. A plasma discharge takes place to deposit an a-Si film on the substrate in an atmosphere in which reactive and carrier passes are supplied to the chamber. The substrate is still left in the chamber to carry out dehydrogenation of the a-Si film after the same is deposited on the substrate. While the carrier gas is supplied to the chamber during the leaving period of time, the pressure of the chamber is set higher than during the leaving period of time. The pressure of the chamber is set higher than during the deposition the pressure of the chamber is set higher. After the dehydrogenation treatment, the substrate is taken out from the chamber.
    Type: Application
    Filed: April 2, 2004
    Publication date: October 7, 2004
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Shinichi Kawamura
  • Patent number: 6790571
    Abstract: An electrophotographic photoconductor has an electroconductive support, and a photoconductive layer formed thereon containing as an effective component an aromatic polycarbonate resin having a structural unit of formula (2) and a structural unit with charge transporting properties, each of the structural units being contained in an amount of 5 wt. % or more of the total weight of the polycarbonate resin. There is disclosed an aromatic polycarbonate resin having a structural unit of formula (1) and the structural unit of formula (2), with the relationship between the composition ratios being 0<k/(k+j)<1 when the composition ratio of the structural unit (1) is k and that of the structural unit (2) is j, or an aromatic polycarbonate resin having a repeat unit of formula (3). The formulas (1) to (3) are specified in the specification.
    Type: Grant
    Filed: January 22, 2002
    Date of Patent: September 14, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinichi Kawamura, Masaomi Sasaki, Kazukiyo Nagai, Kohkoku Ri, Susumu Suzuka, Katsuhiro Morooka
  • Publication number: 20040165721
    Abstract: An encryption/decryption unit includes a first data encryption/decryption section for performing an encryption or decryption process, a first data substitution section for performing data substitution of an output from the first encryption/decryption section according to a predetermined permutation table, a second data encryption/decryption section for performing an encryption or decryption process for an output from the first data substitution section, a second data substitution section for performing data substitution of an output from the second data encryption/decryption section according to a predetermined permutation table, and a third data encryption/decryption section for performing an encryption or decryption process for an output from the second data substitution section.
    Type: Application
    Filed: March 2, 2004
    Publication date: August 26, 2004
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Fumihiko Sano, Shinichi Kawamura, Hideo Shimizu
  • Publication number: 20040160543
    Abstract: In an electrode substrate used in a liquid crystal display device, a contact hole for connecting a signal line to a drain electrode of a pixel thin film transistor is provided in a position overlapping a pixel electrode in order to improve yields by reducing a short circuit between adjacent pixel electrodes. With this configuration, the contact hole does not exist at a boundary between the two adjacent pixel electrodes. Accordingly, the pixel electrodes do not suffer an influence of an electrode material remaining at a recess of the contact hole, and a short circuit between the adjacent pixel electrodes can be thereby prevented.
    Type: Application
    Filed: February 4, 2004
    Publication date: August 19, 2004
    Applicant: TOSHIBA MATSUSHITA DISPLAY TECHNOLOGY CO., LTD.
    Inventors: Hideyuki Takahashi, Kohei Nagayama, Mamoru Furuta, Shinichi Kawamura, Toshihiro Ninomiya, Koji Soma
  • Publication number: 20040131960
    Abstract: An electrophotographic photoconductor has an electroconductive support and a photoconductive layer which is formed thereon and contains at least one resin of a polyurethane resin, a polyester resin, or a polycarbonate resin, each resin having at least a structural unit of formula (1): 1
    Type: Application
    Filed: December 16, 2003
    Publication date: July 8, 2004
    Applicant: RICOH COMPANY, LTD.
    Inventors: Shinichi Kawamura, Kazukiyo Nagai, Tomoyuki Shimada, Chiaki Tanaka, Michihiko Namba
  • Patent number: 6730368
    Abstract: A method of preparing a poly-crystalline silicon (p-Si) film is provided with efficient dehydrogenation treatment of an amorphous silicon (a-Si) film deposited by a plasma enhanced chemical deposition (PECVD) process. A substrate is received in a process chamber of a PECVD system. A plasma discharge takes place to deposit an a-Si film on the substrate in an atmosphere in which reactive and carrier passes are supplied to the chamber. The substrate is still left in the chamber to carry out dehydrogenation of the a-Si film after the same is deposited on the substrate. While the carrier gas is supplied to the chamber during the leaving period of time, the pressure of the chamber is set higher than during the leaving period of time. The pressure of the chamber is set higher than during the deposition the pressure of the chamber is set higher. After the dehydrogenation treatment, the substrate is taken out from the chamber.
    Type: Grant
    Filed: December 20, 1999
    Date of Patent: May 4, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Shinichi Kawamura