Patents by Inventor Masuo Umemoto

Masuo Umemoto 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: 6130797
    Abstract: Virtual tracks are set so that the rotation center of a magnetic recording medium or the vicinity of the rotation center coincides with the track center of the data information, and positioning servo control is performed. Thus, since it is not necessary to faithfully follow the track center line specified by the servo information that is previously recorded on the magnetic recording medium or magnetooptical recording medium, a vibration is not easily caused in synchronism with the rotation. Therefore, when the rotation center and the pattern center are deviated from each other, since a vibration is not caused in synchronism with the rotation, the magnetic head of the magnetic recorder or the magnetooptical head of the magnetooptical recorder is able to follow tracks with higher precision. Accordingly, the recording density can be increased.
    Type: Grant
    Filed: September 16, 1997
    Date of Patent: October 10, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Kyo Akagi, Yoshihiro Shiroishi, Reijiro Tsuchiya, Takehiko Hamaguchi, Masuo Umemoto, Mikio Suzuki, Takashi Kawabe, Katsuro Watanabe, Kiyoshi Matsumoto, Atsushi Saito, Kouichirou Wakabayashi, Yosuke Hamada
  • Patent number: 5881071
    Abstract: A digital write-and-read method and a signal processing apparatus wherein a write encoder includes a bit distribution circuit for dividing an input data block into n (n: 2 or more) series of bit strings and outputting them in parallel, a first coding circuit for executing predetermined coding for each of data series so distributed and a second coding circuit for converting the output bit series D1 to D3 of the first coding circuit to an n-bit channel code by looking up the previous channel code information, and wherein the second coding circuit executes coding by using a combination having a large Euclidean distance in a partial response equalization output taking inter-symbol interference of at least three bits into consideration as a pair.
    Type: Grant
    Filed: March 6, 1997
    Date of Patent: March 9, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Alexander Kuznetsov, Masuo Umemoto, Naoya Kobayashi, Hideki Sawaguchi
  • Patent number: 5786952
    Abstract: A magnetic digital storage method and system which can improve a recording density and can reduce a cross-talk upon reproducing. An inputted high-speed digital signal is converted to a plurality of low-speed digital signal sequences by a recording circuit and each of the low-speed signal sequence is recorded onto a plurality of adjacent recorded tracks of a recording medium by integrated parallel recording heads. One servo signal is commonly recorded to the plurality of recorded tracks. Further, when recording the digital signal to the adjacent recorded tracks of the recording medium, a delay of a signal that is applied to each recording head is adjusted such that the phases of magnetic transition points given by the recording signal in the adjacent recorded tracks are not identical in the circumferential direction.
    Type: Grant
    Filed: November 22, 1995
    Date of Patent: July 28, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Masuo Umemoto, Yoshihiro Shiroishi, Reijiro Tsuchiya, Kyo Akagi, Takehiko Hamaguchi, Takashi Kawabe, Atsushi Saito, Kouichirou Wakabayashi
  • Patent number: 5594756
    Abstract: A decision feedback equalization circuit which can be operated at a high speed with a low cost as well as a high-speed digital data communication system and a high-speed digital data recording system using the equalization circuit are disclosed. The decision feedback equalization circuit has data memories which correspond to the number of available values in decision result and in which feedback signals corresponding to all the next decision results are previously prepared as candidates so that a suitable one of the feedback signal candidates is selected and fed back based on the obtained decision result, thus realizing high-speed operation of a feedback loop.
    Type: Grant
    Filed: June 20, 1995
    Date of Patent: January 14, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Wataru Sakurai, Hideki Sawaguchi, Naoki Satoh, Masuo Umemoto
  • Patent number: 5552940
    Abstract: A method and an apparatus for digital signal recording and/or reproduction are disclosed in which tracks are formed sequentially on a recording medium by use of a head unit mounted on a rotary cylinder, an input digital data is recorded in the recording medium, and the digital data thus recorded is reproduced. The input digital data is modulated into a code word having at least d (d: an integer of at least two) successive bits of high- and low-level data in a signal waveform recorded in the recording medium. The timebase of the code word is compressed. The compressed code word is recorded in the tracks of the recording medium by use of the head unit. The code word recorded and compressed in the recording medium is reproduced. The timebase of the reproduced code word is expanded, and the input digital data is reproduced from the expanded code word.
    Type: Grant
    Filed: May 3, 1995
    Date of Patent: September 3, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Masuo Umemoto, Hirotake Ishii, Hidehiko Sawamura, Yoshizumi Eto
  • Patent number: 5247401
    Abstract: A replay equalization circuit for reproducing digital image information recorded on a recording medium includes a transducer for reading the digital image information, an equalization circuit connected to the transducer for equalizing an output of the transducer based on a speed information input, a clock recovery circuit connected to the equalization circuit for extracting a clock signal from an output of the equalization circuit for latching the output of the equalization circuit in response to the clock signal.
    Type: Grant
    Filed: June 12, 1989
    Date of Patent: September 21, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Masuo Umemoto, Hidehiko Sawamura, Yoshizumi Eto
  • Patent number: 4868853
    Abstract: A demodulation circuit for demodulating a modulated digital including a unit for detecting a specific pattern contained in a series of data before modulation, a unit for judging the phase relation between the specific pattern and a clock pulse used for demodulation, a unit for performing a counting operation on the basis of the result of said judgment, and a unit for controlling the phase of said clock pulse for demodulation on the basis of the count.
    Type: Grant
    Filed: April 14, 1988
    Date of Patent: September 19, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Morishi Izumita, Seiichi Mita, Nobukazu Doi, Masuo Umemoto, Hiroto Yamauchi, Shigeaki Fujino, Nobuo Murata
  • Patent number: 4802192
    Abstract: An original code series containing a synchronizing code is divided into code series, n in number so as to reduce an operation rate to 1/n (n is a positive integer). The detection of a synchronizing pattern is conducted on the basis of a fact that an original synchronizing pattern is transformed into any of patterns of n kinds based on the phase of division.
    Type: Grant
    Filed: February 10, 1987
    Date of Patent: January 31, 1989
    Assignees: Hitachi, Ltd., Hitachi Denshi Kabushiki Kaisha
    Inventors: Yoshizumi Eto, Kazuyuki Takeshita, Hidehiro Kanada, Masuo Umemoto
  • Patent number: 4791495
    Abstract: A digital recording and reproducing system wherein luminance signals digitized and converted into the low speed signals and chrominance signals digitized at the time of recording are distributed among a plural number of channels and the signals of the plural number of channels are recorded respectively on a recording medium. At the time of the reproduction, the signals of the plural number of the channels are reproduced respectively from the recording medium and combined to form the luminance signals and the chrominance signals respectively. The luminance signals in the combined signal are converted into a high speed signal and output terminals for outputting dubbing signals from the system for dubbing the signals are led. The output side of a low speed-to-high speed converter and a channel combination circuit.
    Type: Grant
    Filed: May 13, 1986
    Date of Patent: December 13, 1988
    Assignees: Hitachi Denshi Kabushiki Kaisha, Hitachi Ltd.
    Inventors: Masuo Umemoto, Yoshizumi Eto, Shinichi Miyazaki, Hidehiro Kanada, Hitoshi Katayama, Yuichi Michikawa
  • Patent number: 4775897
    Abstract: Disclosed is an apparatus in which a picture signal is converted into digital signals and the digital signals are recorded into a recording medium, and which is suitable to perform dubbing of the digital signals reproduced from the recording medium. The apparatus employs the component method in which a luminance signal and chrominance signals constituting a picture signal are recorded separately from each other. According to the component method, the sampling frequency of the chrominance signal is set to be about 1/3-1/4 of that of the luminance signal, and therefore the recording/reproducing of a picture signal is carried out after the bit rate of the digital luminance signal is converted into a value equal to the bit rate of the digital chrominance signal.
    Type: Grant
    Filed: May 27, 1986
    Date of Patent: October 4, 1988
    Assignees: Hitachi, Ltd., Hitachi Denshi Kabushiki Kaisha
    Inventors: Masuo Umemoto, Yoshizumi Eto, Shinichi Miyazaki, Hidehiro Kanada, Hitoshi Katayama, Yuichi Michikawa
  • Patent number: 4737863
    Abstract: Video signal components including the luminance and color signals are sampled using a clock generator and dividers, and the resultant signals are coded through a plurality of channels and are recorded in a video tape recorder. In order to suppress and disperse in the screen image the effect of an error or a dropout occurring in a channel during a recording/playback process, the coded pixels are distributed to each channel so as to uniformly disperse the pixels associated with each component in the screen image. For this purpose, the pixels on a line perpendicular to the scanning lines on the screen are extracted sequentially from a different channel; consequently, even if a failure takes place in a channel, the erroneous pixel can thus be compensated for by use of the correct pixel just above or below the erroneous pixel.
    Type: Grant
    Filed: July 25, 1985
    Date of Patent: April 12, 1988
    Assignees: Hitachi, Ltd, Hitachi Denshi Kabushiki Kaisha
    Inventors: Yoshizumi Eto, Masuo Umemoto, Sinich Miyazaki
  • Patent number: 4700240
    Abstract: Number data affixed to individual digital data divided into a plurality of data blocks are sequentially read out from a recording medium to be used for determining the write-in positions of the digital data in a memory. For determining the write-in positions of the digital data, the number data of the next write-in position is estimated on the basis of the number data of the current write-in position. Judgment is made as to whether or not the number of times of continuous non-coincidence between the estimated number data and the successively read-out number data exceeds a predetermined setting, and, also judgment is made as to whether or not the number data read out each time falls within a predetermined range. Depending on the results of these judgments, one of the read-out number data and the estimated number data is selected to determine the next write-in position.
    Type: Grant
    Filed: November 5, 1985
    Date of Patent: October 13, 1987
    Assignees: Hitachi, Ltd., Hitachi Denshi Kabushiki Kaisha
    Inventors: Masuo Umemoto, Yoshizumi Eto, Hidehiro Kanada, Morito Rokuda
  • Patent number: 4698811
    Abstract: An apparatus for recording or reproducing codes resulting from digitalizing a picture signal on or from a video tape recorder includes a device for correcting code error produced due to interference in the course of recording or reproducing process. The pixel codes succeeding to one another in time are divided to high-order and low-order bit-blocks, respectively, wherein the high-order bits are used to constitute a pseudo pixel code which is then added with a pixel error correcting code. The pixel code consisting of the high-order bits is added with a bit error correcting code before being recorded. In reproduction, error correction can be realized at higher rate with the aid of the correction codes to improve the quality of reproduced picture.
    Type: Grant
    Filed: July 19, 1985
    Date of Patent: October 6, 1987
    Assignees: Hitachi, Ltd., Hitachi Denshi Kabushiki Kaisha
    Inventors: Yoshizumi Eto, Masuo Umemoto, Hidehiro Kanada, Seiichi Mita
  • Patent number: 4661956
    Abstract: Parity bits (check bits) having a relatively high redundancy are added to upper significant bits of a digital signal, and parity bits having a relatively low redundancy, are added to the lower significant bits of the digital signal. The signal and the parity bits are recorded on a recording medium. The position of an error in a data block group of the lower bits reproduced from the recording medium is estimated as existing in a block in which the error is detected by the check of the data block group of the upper bits, and in the blocks preceding and subsequent to the former.This error correction method is most suitable for a recording and reproduction system of digital video signals.
    Type: Grant
    Filed: February 21, 1985
    Date of Patent: April 28, 1987
    Assignees: Hitachi, Ltd., Hitachi Denshi Kabushiki Kaisha
    Inventors: Morishi Izumita, Seiichi Mita, Masuo Umemoto, Hidehiro Kanada, Morito Rokuda
  • Patent number: 4628297
    Abstract: In the code modulation system for converting input data levels into an output signal in the form of code words by providing M input levels among N input levels assigned to input data with stairlike code weights on the basis of the input levels, (N-M) input levels which are the difference between said N input levels and said M input levels are respectively disposed near transition points where said stairlike code weight is changed, and the code weights are provided with hysteresis in the ascent process and the descent process of the input data level.
    Type: Grant
    Filed: January 30, 1985
    Date of Patent: December 9, 1986
    Assignees: Hitachi, Ltd., Hitachi Denshi Kabushiki Kaisha
    Inventors: Seiichi Mita, Morishi Izumita, Masuo Umemoto, Yoshizumi Eto, Morito Rokuda, Hidehiro Kanada
  • Patent number: 4467347
    Abstract: The present invention relates to a color imaging device which suppresses false color signals appearing in an area where the difference of brightnesses is great in the horizontal or vertical direction.When the correlation between picture elements adjacent in the vertical direction is little and the false signal appears in a boundary part in the vertical direction, the false signal is detected, whereupon a color signal is demodulated by utilizing the correlation between the signals of picture elements in the horizontal direction. On the other hand, when the correlation between picture elements adjacent in the horizontal direction is little and the false signal appears in a boundary part in the horizontal direction, the false signal is detected, whereupon a color signal is demodulated by utilizing the correlation between the signals of picture elements in the vertical direction.As a result, the moire phenomenon attributed to the false color signals can be conspicuously reduced.
    Type: Grant
    Filed: February 5, 1982
    Date of Patent: August 21, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Naoki Ozawa, Shusaku Nagahara, Kenji Takahashi, Masuo Umemoto, Kazuhiro Sato, Morishi Izumita, Toshiyuki Akiyama, Masanori Sato, Koji Kudo
  • Patent number: 4283742
    Abstract: A solid-state imaging apparatus comprising first means for sample-holding spike noise generated from a horizontal switching element constituting the apparatus second means for sample-holding spike noise opposite in phase to the first-mentioned spike noise, and third means for adding outputs of the first and second means.
    Type: Grant
    Filed: September 19, 1979
    Date of Patent: August 11, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Morishi Izumita, Masuo Umemoto, Kazuhiro Sato, Toshiyuki Akiyama, Kenji Takahashi, Shusaku Nagahara
  • Patent number: 4281338
    Abstract: In a solid state color imaging apparatus comprising photo sensitive element arrays arranged horizontally and vertically, means for reading out parallel photo signals of the photo sensitive element arrays on two horizontal lines and delivering the read out photo signals to first and second output circuits, and a mosaic color filter disposed in front of the photo sensitive elements and having luminance filtering counterparts arranged horizontally and vertically one after the other and two types of color filtering counterparts arranged at the remaining positions and on alternate horizontal lines, the horizontal clock from the reading out means has a frequency of 7.16 MHz so that color difference signals having the chrominance subcarrier component of 3.58 MHz are directly obtained in the first and second output circuits.
    Type: Grant
    Filed: August 29, 1979
    Date of Patent: July 28, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Kenji Takahashi, Shusaku Nagahara, Kazuhiro Sato, Masuo Umemoto, Toshiyuki Akiyama, Morishi Izumita
  • Patent number: 4246601
    Abstract: A solid-state color imaging device is provided including a plurality of photosensors which are arrayed in horizontal and vertical directions, and a mosaic color filter made up of filter elements arranged in correspondence with the respective photosensors. The mosaic color filter is arranged such that any group of four adjacent filter elements comprises a first filter which is made for panchromatic transmission, a second filter which is selected from among a first spectral region-transmitting filter, a second spectral region-transmitting filter and a third spectral region-transmitting filter respectively exhibiting different transmission characteristics, and third and fourth filters which are made of complementary color filters which transmit the transmission light component of the second filter and which have transmission components different from each other.
    Type: Grant
    Filed: February 9, 1979
    Date of Patent: January 20, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiro Sato, Shusaku Nagahara, Masuo Umemoto, Toshiyuki Akiyama, Morishi Izumita, Kenji Takahashi, Seiichi Mita
  • Patent number: 4245241
    Abstract: A solid-state color imaging device including a plurality of photosensors which are arrayed in the horizontal and vertical directions, and a mosaic color filter which is made up of filter elements arranged in correspondence with the respective photosensors. Any four adjacent filter elements of the mosaic color filter have different characteristics from one another with the first and second filter elements of the four adjacent filter elements being selected from the group consisting of first, second and third spectral region transmitting filters having different transmission characteristics, and the third and fourth filter elements of the four adjacent filter elements being complementary color filters of the respective first and second filter elements selected and being arranged adjacent the first and second filter elements, respectively, in the vertical direction.
    Type: Grant
    Filed: February 15, 1979
    Date of Patent: January 13, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiro Sato, Masuo Umemoto, Morishi Izumita, Toshiyuki Akiyama, Shusaku Nagahara