Patents by Inventor Fumihiko Nakazawa

Fumihiko Nakazawa 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: 6756973
    Abstract: Surface acoustic waves are excited in two diagonal directions from each of IDTs (excitation elements) disposed on the upper side and the lower side of a non-piezoelectric substrate, and the surface acoustic waves propagated on a detection region are received by IDTs (receiving elements) disposed on the left side and right side of the non-piezoelectric substrate so that a position of an object touching the non-piezoelectric substrate is detected based on the reception results. In each IDT, comb-like electrode fingers are joined to two facing electrode bases (signal electrode and ground electrode) in such a manner that the comb-like electrode fingers are inclined from a facing direction of the electrode bases.
    Type: Grant
    Filed: May 30, 2001
    Date of Patent: June 29, 2004
    Assignee: Fujitsu Limited
    Inventors: Satoshi Sano, Fumihiko Nakazawa, Takashi Matsuda, Yoshio Satoh, Takashi Katsuki, Yuji Takahashi
  • Patent number: 6750853
    Abstract: A surface acoustic waves is excited from an excitation element disposed on a substrate, the surface acoustic wave propagated on the substrate is received by a receiving element positioned on the substrate so as to face the excitation element, and the position of an object touching the substrate is detected based on the reception result. The wave number of a burst wave applied to excite the excitation element is made equal to the number of the comb-like electrode fingers of an IDT of the excitation element.
    Type: Grant
    Filed: September 25, 2001
    Date of Patent: June 15, 2004
    Assignee: Fujitsu Limited
    Inventors: Yuji Takahashi, Fumihiko Nakazawa, Satoshi Sano, Takashi Katsuki
  • Publication number: 20040104827
    Abstract: Each of an excitation element for exciting surface acoustic waves in two directions and a receiving element for receiving surface acoustic waves from two directions is constructed by forming a comb-like electrode on the front surface of a piezoelectric body in the form of a thin film and a plate electrode on the rear surface thereof. The comb-like electrode on the front surface has one line of bus electrode, and a plurality of electrode fingers which are extended from the bus electrode and bent in V-shape in the middle. The voltage in the excitation element and in the receiving element is controlled by providing a terminal resistance for preventing reflection of an applied AC voltage at the terminal end, between the terminal end portion of the comb-like electrode and the plate electrode, or adjusting the resistance value of the bus electrode and/or the plate electrode, or adjusting the capacitance value between the electrode finger and the plate electrode.
    Type: Application
    Filed: November 12, 2003
    Publication date: June 3, 2004
    Applicant: FUJITSU LIMITED
    Inventors: Takashi Katsuki, Fumihiko Nakazawa, Satoshi Sano, Yuji Takahashi
  • Publication number: 20040090432
    Abstract: A burst wave is applied to an excitation element of a touch panel main body from an oscillation section so as to excite surface acoustic waves, and the excited surface acoustic waves are received by a receiving element of the touch panel main body. The received signals are A/D converted by a receiving section, and a control section calculates the contact position and the contact width of the object in contact with the touch panel main body, based on time-series changes in the received strength. Based on the received strength of surface acoustic waves, the control section controls the wave number of the burst wave to be applied to the excitation element.
    Type: Application
    Filed: October 30, 2003
    Publication date: May 13, 2004
    Applicant: FUJITSU LIMITED,
    Inventors: Yuji Takahashi, Fumihiko Nakazawa, Satoshi Sano, Takashi Katsuki
  • Publication number: 20040032401
    Abstract: A substrate made of glass serves both as a substrate for a touch panel and as that for a front light, and has both functions of propagating an ultrasonic wave in order to detect a touched position, and propagating light emitted from a light source to guide the light toward a reflective-type liquid crystal display. In the case where an image on the liquid crystal display is made visible by external light, external light which has been transmitted through the substrate is reflected by the liquid crystal display, and the reflected light is again transmitted through the substrate to be emitted from the front face. In the case where the front light function is used, light which has been introduced into the substrate from the light source is reflected by the liquid crystal display, and the reflected light is transmitted through the substrate to be emitted from the front face.
    Type: Application
    Filed: August 19, 2003
    Publication date: February 19, 2004
    Applicant: FUJITSU LIMITED
    Inventors: Fumihiko Nakazawa, Hirokazu Aritake
  • Publication number: 20040027342
    Abstract: Each of excitation elements and receiving elements placed in a frame region of a non-piezoelectric substrate is constructed by forming a comb-like electrode on the front face of a piezoelectric body and forming a plate electrode (solid electrode) on the rear face thereof. The comb-like electrode is composed of a bus electrode and a plurality of V-shaped electrode fingers extended from the bus electrode. Drawn-round wires are provided to connect the comb-like electrode (bus electrode) and plate electrode to external circuits. Surface acoustic waves from the excitation elements located on the upper side and the lower side are simultaneously propagated in two directions respectively and the propagated surface acoustic waves are received by receiving elements located on the left side and the right side respectively.
    Type: Application
    Filed: May 28, 2003
    Publication date: February 12, 2004
    Applicant: FUJITSU LIMITED
    Inventors: Takashi Katsuki, Fumihiko Nakazawa, Satoshi Sano, Yuji Takahashi
  • Publication number: 20030234773
    Abstract: Surface acoustic waves are propagated in a lower-left oblique direction and a lower-right oblique direction from an excitation element located on the upper side of a non-piezoelectric substrate and then received by receiving elements located on the left side and the right side, while surface acoustic waves are propagated in an upper-left oblique direction and an upper-right oblique direction from an excitation element located on the lower side of the non-piezoelectric substrate and then received by the receiving elements located on the left side and the right side. Based on the received results at the two receiving elements, a position of an object in contact with the non-piezoelectric substrate is detected.
    Type: Application
    Filed: January 29, 2003
    Publication date: December 25, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Satoshi Sano, Takashi Katsuki, Yuji Takahashi, Fumihiko Nakazawa
  • Patent number: 6664952
    Abstract: An optical unit of an optical scanning-type touch panel is constructed by providing a light emitting element for emitting infrared laser light, a collimation lens for changing the laser light from the light emitting element into parallel light, a light receiving element for receiving scanning light, a slit plate for limiting incident light on the light receiving element, a polygon mirror for angularly scanning the laser light from the light emitting element, an aperture mirror for limiting light projected onto the polygon mirror from the collimation lens by an aperture and for reflecting the reflected light from the polygon mirror toward the light receiving element, a light receiving lens for focusing the reflected light from the aperture mirror, and a motor for rotating the polygon mirror in a single optical unit main body as one unit.
    Type: Grant
    Filed: April 30, 2001
    Date of Patent: December 16, 2003
    Assignee: Fujitsu Limited
    Inventors: Yasuhide Iwamoto, Satoshi Sano, Fumihiko Nakazawa, Nobuyasu Yamaguchi
  • Patent number: 6627871
    Abstract: An optical position detecting device includes side frames on three sides, which are composed of slide parts and guide parts for guiding the slide parts and provided with light retro-reflectors; and a side frame on one side, which is composed of a slide part and a guide part for guiding the slide part and incorporates two optical units including light emitting elements, polygon mirrors and light receiving elements, and the optical position detecting device is externally fixed to a display apparatus by moving the slide parts.
    Type: Grant
    Filed: June 21, 2002
    Date of Patent: September 30, 2003
    Assignee: Fujitsu Limited
    Inventors: Yasuhide Iwamoto, Satoshi Sano, Fumihiko Nakazawa
  • Publication number: 20030076308
    Abstract: In a touch panel device for detecting a position touched by an object by sensing an attenuation or break of surface acoustic waves, in which IDTs for exciting or receiving surface acoustic waves comprising comb-like electrode fingers aligned along confronting bus electrodes are placed on a peripheral area of a substrate, drawing electrodes connected to the bus electrode positioned closer to the center of the substrate and led out to the peripheral area side of the substrate are provided. Each of the IDT regions segmented by the drawing electrodes is constituted by repetition, and the drawing electrodes are disposed so that impedance in each IDT region becomes equal.
    Type: Application
    Filed: January 25, 2002
    Publication date: April 24, 2003
    Applicant: Fujitsu Limited
    Inventors: Satoshi Sano, Takashi Katsuki, Yuji Takahashi, Fumihiko Nakazawa
  • Publication number: 20030038789
    Abstract: A plurality of excitation elements, each including an IDT and a piezoelectric film, for exciting, respectively, surface acoustic waves, each having a unique center frequency, are formed on one end of a non-piezoelectric substrate, a plurality of receiving elements, each including an IDT and a piezoelectric film, for receiving, respectively, surface acoustic waves, each having a unique center frequency, are formed on the other end of the non-piezoelectric substrate to face the excitation elements, respectively, the center frequencies of the IDTs of the facing excitation element and receiving element are equal, the center frequencies of the IDTs of the excitation elements next to each other are different, and surface acoustic waves are propagated across the non-piezoelectric substrate, between the facing excitation elements and receiving elements so as to detect the position of an object in contact with the non-piezoelectric substrate, based on received results in the receiving elements.
    Type: Application
    Filed: October 23, 2002
    Publication date: February 27, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Fumihiko Nakazawa, Satoshi Sano, Yoshio Satoh, Takashi Matsuda
  • Publication number: 20030020008
    Abstract: The position of a light blocking object is detected not only within a display screen, but also outside the display screen. With the use of the function of detecting the position in a region outside the display screen, it becomes possible to provide virtual buttons in this region and detect dust around a light retro-reflector. Dirt on the light retro-reflector is detected based on the levels of light receiving signals of optical units.
    Type: Application
    Filed: September 24, 2002
    Publication date: January 30, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Yasuhide Iwamoto, Satoshi Sano, Fumihiko Nakazawa, Nobuyasu Yamaguchi
  • Publication number: 20030011577
    Abstract: A touch panel device is provided that can detect a touched position with sufficient resolution and accuracy without requiring high accuracy in process for forming a piezoelectric thin film. In the middle portion of the glass substrate, a substantially rectangular touch area is provided. In the periphery of the touch area, plural transmission comb electrodes arranged along one of the neighboring sides of the touch area and plural reception comb electrodes arranged along the other of the neighboring sides make pairs. Surface acoustic wave signals propagate from the transmission comb electrodes to the reception comb electrodes in a slanting direction with respect to four sides of the touch area. The inside edge of the piezoelectric thin film is formed linearly along the sides of the touch area.
    Type: Application
    Filed: November 5, 2001
    Publication date: January 16, 2003
    Applicant: Fujitsu Limited
    Inventors: Takashi Katsuki, Fumihiko Nakazawa, Satoshi Sano, Yuji Takahashi
  • Patent number: 6492633
    Abstract: In order to measure a scanning light cut-off region, an output of a light receiving element and a threshold value set by an MPU are compared by a comparator and a region where the former is smaller than the latter is measured as the scanning light cut-off region. During one cycle of optical scanning, this threshold value is switched in a plurality of stages according to the scanning angle. By accurately measuring the scanning light cut-off region, the correct position and size of an indicator such as a finger or pen are calculated.
    Type: Grant
    Filed: January 18, 2001
    Date of Patent: December 10, 2002
    Assignee: Fujitsu Limited
    Inventors: Fumihiko Nakazawa, Satoshi Sano, Atsuo Iida, Nobuyasu Yamaguchi, Yasuhide Iwamoto
  • Publication number: 20020171635
    Abstract: A surface acoustic waves is excited from an excitation element disposed on a substrate, the surface acoustic wave propagated on the substrate is received by a receiving element positioned on the substrate so as to face the excitation element, and the position of an object touching the substrate is detected based on the reception result. The wave number of a burst wave applied to excite the excitation element is made equal to the number of the comb-like electrode fingers of an IDT of the excitation element.
    Type: Application
    Filed: September 25, 2001
    Publication date: November 21, 2002
    Applicant: Fujitsu Limited
    Inventors: Yuji Takahashi, Fumihiko Nakazawa, Satoshi Sano, Takashi Katsuki
  • Patent number: 6480187
    Abstract: A recurrence reflection sheet is provided to the outside of at least three sides of a quadrilateral display screen, two light send/receive units, which includes a light scanning element for scanning a light angularly in a plane which is substantially parallel with the display screen, and a light receiving element for receiving a reflected light from the recurrence reflection sheet, are arranged on the outside of the display screen. A cut-off region due to a finger as an indicator is obtained based on an angle of a scanning light in a timing of rise and fall of the received light level of the light receiving element, and a position of the indicator is calculated according to the obtained cut-off region.
    Type: Grant
    Filed: April 17, 1998
    Date of Patent: November 12, 2002
    Assignee: Fujitsu Limited
    Inventors: Satoshi Sano, Fumihiko Nakazawa, Atsuo Iida, Nobuyasu Yamaguchi, Fumitaka Abe
  • Publication number: 20020162949
    Abstract: An optical position detecting device includes side frames on three sides, which are composed of slide parts and guide parts for guiding the slide parts and provided with light retro-reflectors; and a side frame on one side, which is composed of a slide part and a guide part for guiding the slide part and incorporates two optical units including light emitting elements, polygon mirrors and light receiving elements, and the optical position detecting device is externally fixed to a display apparatus by moving the slide parts.
    Type: Application
    Filed: June 21, 2002
    Publication date: November 7, 2002
    Applicant: FUJITSU LIMITED
    Inventors: Yasuhide Iwamoto, Satoshi Sano, Fumihiko Nakazawa
  • Publication number: 20020101408
    Abstract: Surface acoustic waves are excited in two diagonal directions from each of IDTs (excitation elements) disposed on the upper side and the lower side of a non-piezoelectric substrate, and the surface acoustic waves propagated on a detection region are received by IDTs (receiving elements) disposed on the left side and right side of the non-piezoelectric substrate so that a position of an object touching the non-piezoelectric substrate is detected based on the reception results. In each IDT, comb-like electrode fingers are joined to two facing electrode bases (signal electrode and ground electrode) in such a manner that the comb-like electrode fingers are inclined from a facing direction of the electrode bases.
    Type: Application
    Filed: May 30, 2001
    Publication date: August 1, 2002
    Applicant: FUJITSU LIMTED
    Inventors: Satoshi Sano, Fumihiko Nakazawa, Takashi Matsuda, Yoshio Satoh, Takashi Katsuki, Yuji Takahashi
  • Publication number: 20020097231
    Abstract: A touch panel device includes a plurality of input IDTs for exciting surface acoustic waves and a plurality of output IDTs for receiving the surface acoustic waves, corresponding to a plurality of tracks on a non-piezoelectric substrate, and each input IDT has a wideband electrode structure and each output IDT has a matched filter structure for outputting a large output upon receipt of a specific binary signal sequence. A signal obtained by arranging a plurality of specific signal sequences in time series is applied to each input IDT.
    Type: Application
    Filed: April 26, 2001
    Publication date: July 25, 2002
    Applicant: Fujitsu Limited
    Inventors: Yoshio Satoh, Fumihiko Nakazawa, Satoshi Sano
  • Publication number: 20010055006
    Abstract: Laser light emitted by a light emitting element is made parallel light by a collimation lens, passes through an aperture of an aperture mirror, and is then angularly scanned in a plane substantially parallel to a display screen by rotation of a polygon mirror and projected onto a recurrence reflection sheet. Then, after the reflected light from the recurrence reflection sheet is reflected by the polygon mirror and aperture mirror, the light is focused by a condenser lens to enter a light receiving element. The aperture mirror has an asymmetrical shape in the scanning direction and/or the vertical direction about the optical axis, according to a scanning surface opening width of the polygon mirror.
    Type: Application
    Filed: June 7, 2001
    Publication date: December 27, 2001
    Applicant: FUJITSU LIMITED
    Inventors: Satoshi Sano, Yasuhide Iwamoto, Fumihiko Nakazawa, Nobuyasu Yamaguchi