Patent ID: 7075514

Claim:
A coordinate input apparatus which detects three-dimensional position coordinates of an indicating tool used in combination with a display for displaying a window based on two-dimensional coordinates, comprising: storage means for storing a plurality of a set of coordinate values of a plurality of points for defining each of a plurality kinds of a three-dimensional space area which is positioned at a relative coordinate position against a position of the display; coordinate detection means for detecting a three-dimensional absolute coordinate value of the indicating tool in a three-dimensional space area; determination means for determining which three-dimensional space area defined by each of the plurality of the set of coordinate values stored in said storage means the detected three-dimensional absolute coordinate value belongs to; and conversion means for converting, responsive to a determination of said determination means that said three-dimensional absolute coordinate value belongs to said three-dimensional space area, a position of said three-dimensional absolute coordinate value in the three-dimensional space area into a display coordinate value of said display.