Patents by Inventor Keisuke Niishida

Keisuke Niishida 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: 6811241
    Abstract: A first evaluation signal includes a first excitation element adapted to excite pressure fluctuation in liquid contained in the pressure chamber and a first ejection element which follows the excitation element after a first time period to eject a first liquid droplet from the nozzle. A second evaluation signal includes a second excitation element adapted to excite pressure fluctuation in liquid contained in the pressure chamber and a second ejection element which follows the excitation element after a second time period to eject a second liquid droplet from the nozzle which is longer than the first time period. The first evaluation signal is supplied to the pressure generating element to measure a first ejected amount of the first liquid droplet. The second evaluation signal is supplied to the pressure generating element to measure a second ejected amount of the second liquid droplet. An ejected amount ratio of the first ejected amount and the second ejected amount is calculated.
    Type: Grant
    Filed: January 15, 2003
    Date of Patent: November 2, 2004
    Assignee: Seiko Epson Corporation
    Inventors: Keisuke Niishida, Satoru Hosono, Tomoaki Takahashi, Ryoichi Tanaka, Hirofumi Teramae