Patents by Inventor Akio Nakashima

Akio Nakashima 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: 5418575
    Abstract: A color display apparatus for a video information system includes an input for receiving at least one externally applied color component signal, a display device having predetermined color characteristics, and a compensating unit responsive to the at least one externally applied color component signal from the input for compensating at least a portion of the at least one externally applied color component signal in accordance with the predetermined color characteristics of the display device. The display device is responsive to the input and the compensating unit for displaying a color image of the externally applied color component signal.
    Type: Grant
    Filed: February 25, 1994
    Date of Patent: May 23, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Kaneko, Hideaki Ohki, Akio Nakashima, Junichi Ikoma
  • Patent number: 5206760
    Abstract: There is provided the construction of a multiprojection apparatus composed of a plurality of projection units arranged in the vertical and horizontal directions, in which a transparent holding strip having an H-shaped cross section is inserted between screens each composed of a lenticular sheet and a Fresnel lens, and the right and left ends of a multiscreen are supported by elastic support members, or in which a receive member for receiving the screen in the direction of the optical axis and a screen holding device are provided, the receive member has such a shape as not to block projection light corresponding to an image on the screen and is located near a joint of the screen and another screen, and the holding device is disposed on a black stripe of the lenticular sheet and always pulled by an elastic member toward the receive member. Therefore, according to the present invention, it is possible to restrict the missing of information due to joints of the screens.
    Type: Grant
    Filed: March 25, 1992
    Date of Patent: April 27, 1993
    Assignees: Hitachi, Ltd., Hitachi Video & Information System, Inc.
    Inventors: Akio Nakashima, Junichi Ikoma, Yasutoshi Nakashima, Sadayuki Nishimura, Yoshihisa Hosoe, Tatsumi Hasebe, Akira Okamoto
  • Patent number: 4858030
    Abstract: A reproducing apparatus of a video disc player, wherein for a special reproduction such as a fast forward reproduction, or a reverse reproduction from a CLV disc, a field memory is provided for storing video signals of length of one field. A reading-in operation to the field memory is synchronized with a reproduced synchronizing signal. A writing-out operation from the field memory is synchronized with a reference synchronizing signal. A discontinuity of phase caused by a track jump is eliminated, and a stabilized picture on a TV monitor can be provided.
    Type: Grant
    Filed: August 21, 1987
    Date of Patent: August 15, 1989
    Assignees: Hitachi, Ltd., Hitachi Video Engineering, Inc.
    Inventors: Masuo Oku, Yoshimichi Kudo, Tomomitsu Kuroyanagi, Kazuo Kondo, Hisanobu Tsukazaki, Tetsuya Ikeda, Akio Nakashima, Takashi Kimura
  • Patent number: 4745494
    Abstract: A light emitted from a laser diode is reflected by a video disc which is rotated by a spindle motor. The reflected light is modulated by video information recorded on the video disc and converted to an electrical signal by a photodiode array. A signal generated by a trapezoidal generator is sampled with a horizontal synchronizing signal separated from the video information signal. The sampled signal is supplied to the spindle motor for correcting a time base error. A zero crossing point of the trapezoidal waveform is detected and is utilized for controlling the start of a rise portion of the trapezoidal waveform for compensating a DC offset. The trapezoidal waveform is controlled so as to vary an average power supplied to the spindle motor in accordance with a detected rotational speed difference so as to compensate a rotational speed of the spindle motor.
    Type: Grant
    Filed: June 11, 1986
    Date of Patent: May 17, 1988
    Assignees: Hitachi Video Eng. Inc., Hitachi, Ltd.
    Inventors: Atsushi Kaneko, Junichi Ikoma, Akio Nakashima
  • Patent number: 4550348
    Abstract: A video disc player comprising an arm servo system having means for driving a pickup arm with a cartridge mounted thereon to move in parallel with the surface of a disc, and a kicker drive system for driving a stylus tip mounted on the cartridge to be kicked on the basis of the information from a picture signal processing circuit of the pickup upon special reproduction, wherein when the width of a kicker drive pulse in the kicker drive system exceeds a predetermined value, the drive means of the arm servo system is driven to change the balance position of the stylus tip on the surface of the disc.
    Type: Grant
    Filed: October 20, 1985
    Date of Patent: October 29, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Yosinobu Imada, Akio Nakashima
  • Patent number: 4328514
    Abstract: A CRT drive circuit for amplifying a video signal applied through a video signal transmission cable to a level sufficient to drive a CRT wherein a circuit for clamping the video signal to a white level during the entire period when the cable is disconnected is provided at an input stage, a blanking circuit for clamping the video signal to a black level during a flyback period is provided in an intermediate stage, and a D.C. restore circuit for clamping the black level of the video signal output to a level corresponding to a black level input to the CRT is provided at an output stage. When the cable is disconnected, the entire display area of the CRT screen displays white so that the CRT drive circuit can be readily checked for proper operation.
    Type: Grant
    Filed: September 29, 1980
    Date of Patent: May 4, 1982
    Assignee: Hitachi, Ltd.
    Inventors: Akio Nakashima, Yoshimasa Okamoto
  • Patent number: 3979641
    Abstract: A vertical deflection output circuitry for a television receiver wherein two transistors are connected in single ended and push-pull relation, and the output junction point of the two transistors is connected, to a D.C. power source for supplying a higher voltage than that of a power source for the vertical deflection output circuitry, through a switch which is turned off during the vertical scan period and turned on during the vertical retrace period.
    Type: Grant
    Filed: May 28, 1974
    Date of Patent: September 7, 1976
    Assignee: Hitachi, Ltd.
    Inventors: Yoshihiro Arakawa, Akio Nakashima, Shunji Iwabuchi, Kenji Ando
  • Patent number: 3950672
    Abstract: A vertical sweep circuit includes a first transistor supplied with a sawtooth voltage. A voltage drop is developed across a resistor by a vertical sweep current for producing a first voltage across a first load. A second transistor is supplied with the first voltage for producing a second voltage across a second load, and a pair of push-pull connected transistors are supplied with the second voltage for producing the sweep current. An additional transistor of the same conductivity type as the second transistor is included in the circuit. Responsive to the first voltage, the additional transistor produces voltage pulses at a point of connection thereto of an additional load, which is greater than the second load to make the second and additional transistors operate as a linear amplifier transistor and a switching transistor, respectively. Vertical blanking pulses are produced from the voltage pulses.
    Type: Grant
    Filed: June 10, 1974
    Date of Patent: April 13, 1976
    Assignee: Nippon Electric Co., Ltd.
    Inventors: Hirokazu Fukaya, Kenji Andou, Akio Nakashima