Correction of alignment and linearity errors in a stylus input system
View Patent ↗A method and system for correcting alignment and linearity errors in devices using a finger or stylus input device with a display device interactively coupled to a digitizer is disclosed. Touching intersections in a calibration grid on the display device may be performed to create a linearity map. Subsequently, detected stylus input is mapped to a sector in the linearity map, and resultant screen coordinates are calculated using ratios within a reference rectangle corresponding to the detected stylus input and the mapped sector.
1. One or more computer readable media storing computer executable instructions for performing a method of creating a linearity map, said method comprising the steps of:
(i) touching a display device at a plurality of predetermined locations defined by a calibration grid corresponding to the display device, wherein the calibration grid is non-uniform, and the calibration grid comprises a first area of a first calibration density and a second area of a second calibration density different from said first calibration density;
(ii) detecting in a digitizer coupled to the display device, coordinates for each touched predetermined location; and
(iii) recording each predetermined location's screen coordinates and corresponding detected digitizer coordinates.
2. The computer readable media of claim 1 , wherein the calibration grid is displayed on the display device.
3. The computer readable media of claim 1 , wherein the information recorded in step (iii) is recorded in an array.
4. The computer readable media of claim 3 , wherein the array is two-dimensional, and each array element corresponds to an intersection of the calibration grid.
5. The computer readable media of claim 1 , wherein the calibration grid is non-uniform along both its X-axis and Y-axis.
6. One or more computer readable media storing computer executable instructions for performing a method for creating a linearity map, said method comprising the steps of:
(i) detecting touch input on a display device at a plurality of predetermined locations;
(ii) detecting on a digitizer, coordinates for each touched predetermined location; and
(iii) recording each predetermined location's screen coordinates and corresponding detected digitizer coordinates,
wherein a calibration grid displayed on the display device coupled to the digitizer defines the predetermined locations, and
wherein the calibration grid is non-uniform, and comprises a first area of a first density and a second area of a second density.
7. The computer readable media of claim 6 , wherein the first area corresponds to an area of higher distortion within a data processing device, and the second area corresponds to an area of lower distortion within the data processing device.
8. The computer readable media of claim 6 , wherein the information recorded in step (iii) is recorded in a non-linear array.
9. The computer readable media of claim 6 , wherein the calibration grid is non-uniform along both its X-axis and Y-axis.
10. One or more computer readable media storing computer executable instructions for performing a method of creating a linearity map, said method comprising the steps of:
(i) detecting touch input corresponding to a plurality of predetermined locations on a display device, said locations defined by a calibration grid corresponding to the display device, wherein the calibration grid is non-uniform, and the calibration grid comprises a first area of a first calibration density and a second area of a second calibration density different from said first calibration density;
(ii) detecting in a digitizer coupled to the display device, coordinates for each touched predetermined location; and
(iii) recording each predetermined location's screen coordinates and corresponding detected digitizer coordinates,
wherein the first area corresponds to an area of higher distortion within a data processing device, and the second area corresponds to an area of lower distortion within the data processing device.
11. The computer readable media of claim 10 , wherein the calibration grid is displayed on the display device.
12. The computer readable media of claim 10 , wherein the information recorded in step (iii) is recorded in an array.
13. The computer readable media of claim 12 , wherein the array is two-dimensional, and each array element corresponds to an intersection of the calibration grid.
14. The computer readable media of claim 10 , wherein the information recorded in step (iii) is recorded in a non-linear array.
15. The computer readable media of claim 10 , wherein the calibration grid is non-uniform along both its X-axis and Y-axis.