System for determining pointer position, movement, and angle

摘要

An a data input system includes an encoded pad having position encoding and a data input device adapted to image a portion of the encoded pad to determine position and orientation of the data input device relative to the encoded pad. The encoding pad includes a plurality of correlation windows. Each correlation window includes a primary encoding marker in form of vertical line segment and a set of secondary encoding markers in form of diagonal line segments, at least one diagonal line segment intersecting the vertical line segment at an intersection angle. Spacing of the diagonal line segments encodes the X-axis position of the input device relative to the encoding pad. Intersection angle encodes the Y-axis position of the input device relative to the encoding pad. Angle of the primary encoding marker vertical line segment within the frame of the captured image encodes the angular orientation of the input device relative to the axes of the encoded pad.