Patents by Inventor Koh Asai

Koh Asai 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: 4646352
    Abstract: A pair candidate list (73) is formed by selecting minutia pairs with reference to a minutia list (71) showing original position and direction data given for minutiae by principal coordinate systems preliminarily selected on a search and a file fingerprint and those relation data of the minutiae which are substantially independent of the coordinate systems. It is very likely that the pair candidate list shows coarse pairs because the coordinate systems may not yet be optimally matched to each other. One of the coordinate systems is transformed by those optimum amounts to provide transformed position and direction data which are decided by the original position and direction data of the minutia pairs of the pair candidate list. A pair list (86) is formed by precisely selecting minutiae from the pair candidate list with reference to the transformed position and direction data and the original position and direction data given by the other principal coordinate system and to the relation data.
    Type: Grant
    Filed: June 28, 1983
    Date of Patent: February 24, 1987
    Assignee: NEC Corporation
    Inventors: Koh Asai, Hiroyuki Izumisawa, Katsuaki Owada, Seiichiro Kinoshita, Shunji Matsuno
  • Patent number: 4310827
    Abstract: In addition to positions and directions of feature points of a streaked pattern, such as minutiae of a fingerprint on a background, a plurality of novel counts and a density are automatically extracted for each feature point selected as a reference feature point. The density is determined in connection with adjacent feature points that are present in a predetermined neighborhood of the reference feature point. Each count is decided by the number of streaks or ridges intervening between the reference feature point and a related feature point that is nearest to the reference feature point among the feature points in a predetermined sector of the neighborhood.
    Type: Grant
    Filed: April 2, 1980
    Date of Patent: January 12, 1982
    Assignee: Nippon Electric Co., Ltd.
    Inventor: Koh Asai