Patents by Inventor Yoichi Nakagomi

Yoichi Nakagomi 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: 11480860
    Abstract: An illuminator includes a first light source, a second light source, a first lens on which light emitted from the first and second light sources is incident, a second lens disposed in a downstream of the first lens, and a half wave plate. The first lens, the second lens and the half wave plate are arranged along a first axis. The first light source and the second light source are arranged along a plane perpendicular to the first axis. The half wave plate is disposed in the optical axis between the first lens and the second lens, the half wave plate being disposed in a position close to the second lens.
    Type: Grant
    Filed: June 24, 2020
    Date of Patent: October 25, 2022
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Hiroaki Miya, Akihiro Kashiwagi, Tomohiro Takagi, Yoichi Nakagomi
  • Publication number: 20200409247
    Abstract: An illuminator includes a first light source, a second light source, a first lens on which light emitted from the first and second light sources is incident, a second lens disposed in a downstream of the first lens, and a half wave plate. The first lens, the second lens and the half wave plate are arranged along a first axis. The first light source and the second light source are arranged along a plane perpendicular to the first axis. The half wave plate is disposed in the optical axis between the first lens and the second lens, the half wave plate being disposed in a position close to the second lens.
    Type: Application
    Filed: June 24, 2020
    Publication date: December 31, 2020
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hiroaki MIYA, Akihiro KASHIWAGI, Tomohiro TAKAGI, Yoichi NAKAGOMI
  • Patent number: 10237521
    Abstract: According to an aspect of the invention, a discharge lamp driving device includes a discharge lamp driving section, a control section, and a voltage detecting section. The control section is configured to execute a first discharge lamp driving for executing a first control and a second control for supplying a driving current including a direct current and an alternating current to a discharge lamp. In the first discharge lamp driving, the control section executes the first control when the interelectrode voltage is equal to or smaller than a first threshold voltage at predetermined setting timing and executes the second control when the interelectrode voltage is larger than the first threshold voltage at the predetermined setting timing. A rate of the direct current in the second control is larger than a rate of the direct current in the first control.
    Type: Grant
    Filed: March 3, 2016
    Date of Patent: March 19, 2019
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Shun Sato, Tetsuo Terashima, Yoichi Nakagomi
  • Patent number: 9872370
    Abstract: A discharge lamp driving device includes: a discharge lamp driving unit which supplies drive power to a discharge lamp; and a control unit which controls the discharge lamp driving unit according to a waveform of the drive power. The waveform has n launching periods and a low-power mode lighting period. The n launching periods include a first launching period in which the drive power increases toward refresh power that is equal to or above drive power in a low-power mode and equal to or below rated power, and (n?1) launching periods in which the drive power is maintained at the refresh power. The control unit, in an x-th launching period, supplies the discharge lamp with a drive current having a drive frequency equal to or below a drive frequency of a drive current supplied to the discharge lamp in an (x?1)th launching period.
    Type: Grant
    Filed: November 18, 2016
    Date of Patent: January 16, 2018
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Yoichi Nakagomi, Junichi Suzuki
  • Patent number: 9602791
    Abstract: A discharge lamp driving device includes a discharge lamp driving unit configured to supply driving current to a discharge lamp provided with a first electrode and a second electrode, and a controller configured to control the discharge lamp driving unit. The driving current includes a first AC period and a second AC period in which an AC current is supplied. The first AC period includes a plurality of consecutive first unit driving periods each of which is formed of a first polarity period and a second polarity period, a length of the first polarity period being larger than a length of the second polarity period. The second AC period includes a plurality of consecutive second unit driving periods each of which is formed of the first polarity period and the second polarity period, the length of the second polarity period being larger than the length of the first polarity period.
    Type: Grant
    Filed: February 17, 2016
    Date of Patent: March 21, 2017
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Tetsuo Terashima, Yoichi Nakagomi
  • Publication number: 20170076645
    Abstract: In an aspect of a discharge lamp driving device, the controller is configured to supply a driving current to a discharge lamp, the driving current alternately having a first period and a second period. The first period includes a plurality of consecutive first unit driving periods each of which is constituted of a first polarity period and a second polarity period. The second period includes a plurality of consecutive second unit driving periods. In the first unit driving period, a length of one polarity period is larger than the other polarity period, and a duration ratio which is a ratio of the length of the one polarity period to the length of the other polarity period is equal to or more than a predetermined value. In the second unit driving period, the duration ratio is equal to or more than 1, and is less than the predetermined value.
    Type: Application
    Filed: September 1, 2016
    Publication date: March 16, 2017
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Tetsuo TERASHIMA, Yoichi NAKAGOMI
  • Publication number: 20170071052
    Abstract: A discharge lamp driving device includes: a discharge lamp driving unit which supplies drive power to a discharge lamp; and a control unit which controls the discharge lamp driving unit according to a waveform of the drive power. The waveform has n launching periods and a low-power mode lighting period. The n launching periods include a first launching period in which the drive power increases toward refresh power that is equal to or above drive power in a low-power mode and equal to or below rated power, and (n?1) launching periods in which the drive power is maintained at the refresh power. The control unit, in an x-th launching period, supplies the discharge lamp with a drive current having a drive frequency equal to or below a drive frequency of a drive current supplied to the discharge lamp in an (x?1)th launching period.
    Type: Application
    Filed: November 18, 2016
    Publication date: March 9, 2017
    Inventors: Yoichi NAKAGOMI, Junichi SUZUKI
  • Patent number: 9563111
    Abstract: A discharge lamp driving device includes: a discharge lamp driving unit which supplies drive power to a discharge lamp having electrodes; a storage unit which stores information with respect to the discharge lamp; and a control unit which controls the discharge lamp driving unit, wherein the control unit is configured to execute a stationary lighting driving in which first drive power is supplied to the discharge lamp and a high-power driving in which second drive power that is higher than the first drive power is supplied to the discharge lamp, and the control unit sets first execution information of the high-power driving on the basis of first information with respect to the high-power driving stored in the storage unit, at a predetermining setting timing, and controls the discharge lamp driving unit according to the first execution information.
    Type: Grant
    Filed: October 6, 2014
    Date of Patent: February 7, 2017
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Yoichi Nakagomi, Junichi Suzuki, Tetsuo Terashima
  • Patent number: 9532439
    Abstract: A discharge lamp driving device includes: a discharge lamp driving unit which supplies drive power to a discharge lamp; and a control unit which controls the discharge lamp driving unit according to a waveform of the drive power. The waveform has n launching periods and a low-power mode lighting period. The n launching periods include a first launching period in which the drive power increases toward refresh power that is equal to or above drive power in a low-power mode and equal to or below rated power, and (n?1) launching periods in which the drive power is maintained at the refresh power. The control unit, in an x-th launching period, supplies the discharge lamp with a drive current having a drive frequency equal to or below a drive frequency of a drive current supplied to the discharge lamp in an (x?1)th launching period.
    Type: Grant
    Filed: October 1, 2014
    Date of Patent: December 27, 2016
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Yoichi Nakagomi, Junichi Suzuki
  • Patent number: 9509965
    Abstract: A discharge lamp driving device includes: a discharge lamp driving unit which supplies drive power to a discharge lamp; and a control unit which controls the discharge lamp driving unit. The control unit is configured to execute a first driving in which first drive power is supplied to the discharge lamp and a second driving in which second drive power that is equal to or higher than the first drive power and equal to or lower than rated power of the discharge lamp is supplied to the discharge lamp. The control unit executes the second driving in a launching period of the discharge lamp, and adjusts a heat load applied to the discharge lamp in the second driving executed in the launching period, according to a degree of deterioration of the discharge lamp.
    Type: Grant
    Filed: October 3, 2014
    Date of Patent: November 29, 2016
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Yoichi Nakagomi, Junichi Suzuki, Tetsuo Terashima
  • Publication number: 20160270197
    Abstract: According to an aspect of the invention, a discharge lamp driving device includes a discharge lamp driving section, a control section, and a voltage detecting section. The control section is configured to execute a first discharge lamp driving for executing a first control and a second control for supplying a driving current including a direct current and an alternating current to a discharge lamp. In the first discharge lamp driving, the control section executes the first control when the interelectrode voltage is equal to or smaller than a first threshold voltage at predetermined setting timing and executes the second control when the interelectrode voltage is larger than the first threshold voltage at the predetermined setting timing. A rate of the direct current in the second control is larger than a rate of the direct current in the first control.
    Type: Application
    Filed: March 3, 2016
    Publication date: September 15, 2016
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Shun SATO, Tetsuo TERASHIMA, Yoichi NAKAGOMI
  • Patent number: 9439274
    Abstract: A discharge lamp driving device according to an aspect includes: a discharge lamp driving section configured to supply driving power to a discharge lamp including electrodes and a control section configured to control the discharge lamp driving section. The control section is configured to perform a steady lighting driving for supplying first driving power to the discharge lamp and a high power driving for supplying second driving power larger than the first driving power to the discharge lamp. The magnitude of heat load on the electrodes by the high power driving changes on the basis of the first driving power.
    Type: Grant
    Filed: July 9, 2015
    Date of Patent: September 6, 2016
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Yoichi Nakagomi, Tetsuo Terashima
  • Publication number: 20160249440
    Abstract: A discharge lamp driving device includes a discharge lamp driving unit configured to supply driving current to a discharge lamp provided with a first electrode and a second electrode, and a controller configured to control the discharge lamp driving unit. The driving current includes a first AC period and a second AC period in which an AC current is supplied. The first AC period includes a plurality of consecutive first unit driving periods each of which is formed of a first polarity period and a second polarity period, a length of the first polarity period being larger than a length of the second polarity period. The second AC period includes a plurality of consecutive second unit driving periods each of which is formed of the first polarity period and the second polarity period, the length of the second polarity period being larger than the length of the first polarity period.
    Type: Application
    Filed: February 17, 2016
    Publication date: August 25, 2016
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Tetsuo TERASHIMA, Yoichi NAKAGOMI
  • Patent number: 9398275
    Abstract: A discharge lamp driving device includes: a discharge lamp driving unit that supplies a driving current for driving a discharge lamp to the discharge lamp; and a control unit that controls the discharge lamp driving unit. The control unit controls the discharge lamp driving unit such that the driving current having driving periods is supplied to the discharge lamp, the driving period including: a mixing period which alternately has an AC period in which an alternating current is supplied to the discharge lamp and a first DC period in which a direct current is supplied to the discharge lamp and a second DC period which is provided immediately after the mixing period and in which a direct current having a polarity which is opposite to that of the direct current in the first DC period is supplied to the discharge lamp.
    Type: Grant
    Filed: March 3, 2015
    Date of Patent: July 19, 2016
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Junichi Suzuki, Yoichi Nakagomi
  • Patent number: 9338416
    Abstract: A discharge lamp driving device includes: a discharge lamp driving unit that supplies a driving current to the discharge lamp; and a control unit that controls the discharge lamp driving unit. The driving current having driving periods is supplied, the driving period including: a mixing period which alternately has an AC period in which an alternating current is supplied and a first DC period in which a direct current is supplied, a second DC period which is provided immediately after the mixing period and in which a direct current having a polarity which is the same as that of the direct current in the first DC period is supplied, and a third DC period which is provided immediately after the second DC period and in which a direct current having a polarity opposite to that of the direct current in the second DC period is supplied.
    Type: Grant
    Filed: March 3, 2015
    Date of Patent: May 10, 2016
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Junichi Suzuki, Yoichi Nakagomi
  • Patent number: 9288884
    Abstract: A discharge lamp lighting method for controlling lighting of a discharge lamp includes varying an amount of generation (current value) of overshoot and undershoot generated in a waveform of a drive current that is applied when driving the discharge lamp, according to a magnitude of drive power supplied to the discharge lamp and a drive mode.
    Type: Grant
    Filed: December 19, 2013
    Date of Patent: March 15, 2016
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Yoichi Nakagomi, Tetsuo Terashima
  • Publication number: 20160066399
    Abstract: A discharge lamp driving device according to an aspect includes: a discharge lamp driving section configured to supply driving power to a discharge lamp including electrodes and a control section configured to control the discharge lamp driving section. The control section is configured to perform a steady lighting driving for supplying first driving power to the discharge lamp and a high power driving for supplying second driving power larger than the first driving power to the discharge lamp. The magnitude of heat load on the electrodes by the high power driving changes on the basis of the first driving power.
    Type: Application
    Filed: July 9, 2015
    Publication date: March 3, 2016
    Inventors: Yoichi NAKAGOMI, Tetsuo TERASHIMA
  • Publication number: 20150264787
    Abstract: A discharge lamp driving device includes: a discharge lamp driving unit that supplies a driving current for driving a discharge lamp to the discharge lamp; and a control unit that controls the discharge lamp driving unit. The control unit controls the discharge lamp driving unit such that the driving current having driving periods is supplied to the discharge lamp, the driving period including: a mixing period which alternately has an AC period in which an alternating current is supplied to the discharge lamp and a first DC period in which a direct current is supplied to the discharge lamp and a second DC period which is provided immediately after the mixing period and in which a direct current having a polarity which is opposite to that of the direct current in the first DC period is supplied to the discharge lamp.
    Type: Application
    Filed: March 3, 2015
    Publication date: September 17, 2015
    Inventors: Junichi SUZUKI, Yoichi NAKAGOMI
  • Publication number: 20150264786
    Abstract: A discharge lamp driving device includes: a discharge lamp driving unit that supplies a driving current to the discharge lamp; and a control unit that controls the discharge lamp driving unit. The driving current having driving periods is supplied, the driving period including: a mixing period which alternately has an AC period in which an alternating current is supplied and a first DC period in which a direct current is supplied, a second DC period which is provided immediately after the mixing period and in which a direct current having a polarity which is the same as that of the direct current in the first DC period is supplied, and a third DC period which is provided immediately after the second DC period and in which a direct current having a polarity opposite to that of the direct current in the second DC period is supplied.
    Type: Application
    Filed: March 3, 2015
    Publication date: September 17, 2015
    Inventors: Junichi SUZUKI, Yoichi NAKAGOMI
  • Publication number: 20150103322
    Abstract: A discharge lamp driving device includes: a discharge lamp driving unit which supplies drive power to a discharge lamp; and a control unit which controls the discharge lamp driving unit according to a waveform of the drive power. The waveform has n launching periods and a low-power mode lighting period. The n launching periods include a first launching period in which the drive power increases toward refresh power that is equal to or above drive power in a low-power mode and equal to or below rated power, and (n?1) launching periods in which the drive power is maintained at the refresh power. The control unit, in an x-th launching period, supplies the discharge lamp with a drive current having a drive frequency equal to or below a drive frequency of a drive current supplied to the discharge lamp in an (x?1)th launching period.
    Type: Application
    Filed: October 1, 2014
    Publication date: April 16, 2015
    Inventors: Yoichi NAKAGOMI, Junichi SUZUKI