Patents by Inventor Toshimasa Ogawa

Toshimasa Ogawa 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).

  • LED lighting device
    Patent number: 9204507
    Abstract: This LED lighting device makes a maximum current to minimum current flowing in an LED a target proportion regardless of LED driving circuit performance and without erroneous operation. An LED lighting device (1) is provided with: an LED circuit (5) that includes at least one LED (1-5); a bypass means (6a) inserted in parallel with the LEDs (1-5); and an LED driving circuit (4) that supplies current by duty control to the LEDs (1-5) and the bypass means (6a). When a prescribed minimum current flows in the LED circuit (5), the LED driving circuit (4) supplies current in which a portion of current flowing in the bypass means (6a) is added to this minimum current and carries out control of the added current by a switching element (TR1) connected in series to the LED circuit (5) and the bypass means (6a).
    Type: Grant
    Filed: September 21, 2012
    Date of Patent: December 1, 2015
    Assignee: SHARP KABUSHIKI KAISHA
    Inventors: Shogo Fukuda, Tomoyuki Ichiza, Toshimasa Ogawa
  • LED LIGHTING DEVICE
    Publication number: 20140368129
    Abstract: This LED lighting device makes a maximum current to minimum current flowing in an LED a target proportion regardless of LED driving circuit performance and without erroneous operation. An LED lighting device (1) is provided with: an LED circuit (5) that includes at least one LED (1-5); a bypass means (6a) inserted in parallel with the LEDs (1-5); and an LED driving circuit (4) that supplies current by duty control to the LEDs (1-5) and the bypass means (6a). When a prescribed minimum current flows in the LED circuit (5), the LED driving circuit (4) supplies current in which a portion of current flowing in the bypass means (6a) is added to this minimum current and carries out control of the added current by a switching element (TR1) connected in series to the LED circuit (5) and the bypass means (6a).
    Type: Application
    Filed: September 21, 2012
    Publication date: December 18, 2014
    Inventors: Shogo Fukuda, Tomoyuki Ichiza, Toshimasa Ogawa