Coordinate determining device using spatial filters
    1.
    发明授权
    Coordinate determining device using spatial filters 失效
    使用空间滤波器的坐标确定装置

    公开(公告)号:US4963703A

    公开(公告)日:1990-10-16

    申请号:US381765

    申请日:1989-07-18

    CPC分类号: G06F3/046

    摘要: A digitizing tablet is disclosed in which two sets of circuitous conductive lines form grids each connected at one end to a surrounding conductive loop. All outputs are measured from the conductive loop as a multiplexor sequentially grounds the grids one at a time. The outputs are fed through linear spatial filters which are used to produce intermediate signals which are in turn combined to arrive at raw position signals for a position indicating coil located over the work surface. Separate sets of linear spatial filters may be used to produce two raw position signals differently responsive to tilt which can then be combined to arrive at a true position signal insensitive to tilt.