Position detecting method and apparatus for detecting a plurality of position indicators
First Claim
1. A method for detecting the position of a first position indicator and a second position indicator on the surface of a sensor unit, the sensor unit comprising a plurality of conductive coils, a means for scanning the coils, and a means for detecting an interaction between the coils and the first position indicator and between the coils and the second position indicator, the method comprising the steps of:
- designating a first set of coils;
scanning the first set of coils for the first position indicator and detecting an interaction between the first set of coils and the first position indicator;
designating a second set of coils based upon the detected interaction between the first set of coils and the first position indicator;
scanning the second set of coils for the first position indicator and detecting an interaction between the second set of coils and the first position indicator;
designating a third set of coils; and
scanning the third set of coils for the second position indicator.
2 Assignments
0 Petitions
Accused Products
Abstract
A method and apparatus for detecting the positions of a plurality of position indicators using a tablet or the like. After a first position indicator has been detected by an all-scan step, sensor coils to be scanned are specified according to the positional information of the first position indicator. A sector-scan step then performs a more detailed detection of the position of the first position indicator. The sector-scan step and the all-scan step for detecting the approximate position of a second position indicator are implemented alternately. The sector-scan is carried out more frequently than the all-scan.
56 Citations
37 Claims
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1. A method for detecting the position of a first position indicator and a second position indicator on the surface of a sensor unit, the sensor unit comprising a plurality of conductive coils, a means for scanning the coils, and a means for detecting an interaction between the coils and the first position indicator and between the coils and the second position indicator, the method comprising the steps of:
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designating a first set of coils;
scanning the first set of coils for the first position indicator and detecting an interaction between the first set of coils and the first position indicator;
designating a second set of coils based upon the detected interaction between the first set of coils and the first position indicator;
scanning the second set of coils for the first position indicator and detecting an interaction between the second set of coils and the first position indicator;
designating a third set of coils; and
scanning the third set of coils for the second position indicator. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19)
indicating an interaction between the third set of coils and the second position indicator;
designating a fourth set of coils based upon the detected interaction between the third set of coils and the second position indicator; and
scanning the fourth set of coils for the second position indicator and detecting an interaction between the fourth set of coils and the second position indicator.
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13. The method as claimed in claim 7, further comprising the steps of:
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indicating an interaction between the third set of coils and the second position indicator;
designating a fourth set of coils based upon the detected interaction between the third set of coils and the second position indicator; and
scanning the fourth set of coils for the second position indicator and detecting an interaction between the fourth set of coils and the second position indicator;
wherein the step of detecting an interaction between the third set of coils and the second position indicator comprises the substeps of defining a plurality of areas on the surface of the sensor unit and identifying the area indicated by the second position detector; and
wherein the fourth set of coils consist of the coils in the area indicated by the second position detector.
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14. The method as claimed in claim 1, further comprising the steps of repetitively scanning the second set of coils and the third set of coils, wherein the second set of coils is scanned more frequently than the third set of coils.
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15. The method as claimed in claim 14, wherein the relative frequency of scanning the second and third sets of coils may be changed.
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16. The method as claimed in claim 13, further comprising the steps of repetitively scanning the second and fourth sets of coils.
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17. The method as claimed in claim 6, wherein the second and fourth sets of coils are alternativly scanned.
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18. The method as claimed in claim 16, wherein the second set of coils is scanned more frequently than the third set of coils, and wherein the first position indicator requires closer tracking than the second position indicator.
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19. The method as claimed in claim 18, wherein the relative frequency of scanning the second and third sets of coils may be changed.
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20. A method for detecting the position of a first position indicator and a second position indicator on the surface of a sensor unit, the sensor unit comprising a plurality of conductive coils arranged in the same plane as the surface, a means for scanning the coils, and a means for detecting an interaction between the coils and the first position indicator and between the coils and the second position indicator, the method comprising the steps of:
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scanning the entire surface for the first position indicator and detecting an interaction between the first position indicator and the coils;
scanning a portion less than the entire surface for the first position indicator, the portion being selected based upon the detected interaction between the first position indicator and the coils; and
scanning the entire surface for the second position indicator. - View Dependent Claims (21, 22, 23, 24, 25)
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26. A method for detecting the position of a first position indicator responsive to a first frequency and a second position indicator responsive to a second frequency on the surface of a sensor unit, the sensor unit comprising a plurality of conductive coils arranged in the same plane as the surface, a means for scanning the coils, and a means for detecting an interaction between the coils and the first position indicator and between the coils and the second position indicator, the method comprising the steps of:
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scanning the entire surface for the first position indicator;
scanning the entire surface for the second position indicator; and
repeating the scan of the entire surface for the first position indicator and the scan of the entire surface for the second position indicator, wherein the scan of the entire surface area for the first position indicator occurs more often than the scan of the entire surface area for the second position indicator. - View Dependent Claims (27, 28)
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29. A sensor unit for detecting the position of a first position indicator and a second position indicator on the surface of a sensor unit, the sensor unit comprising:
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a plurality of conductive coils; and
a means for scanning the coils and for detecting an interaction between the coils and the first position indicator and between the coils and the second position indicator, said means comprising;
means for designating a first set of coils;
means for scanning the first set of coils for the first position indicator and detecting an interaction between the first set of coils and the first position indicator;
means for designating a second set of coils based upon the detected interaction between the first set of coils and the first position indicator;
means for scanning the second set of coils for the first position indicator and detecting an interaction between the second set of coils and the first position indicator;
means for designating a third set of coils; and
means for scanning the third set of coils for the second position indicator. - View Dependent Claims (30, 31, 32, 33, 34, 35)
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36. A sensor unit for detecting the position of a first position indicator and a second position indicator on the surface of a sensor unit, the sensor unit comprising:
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a plurality of conductive coils; and
a means for scanning the coils and for detecting an interaction between the coils and the first position indicator and between the coils and the second position indicator, said means comprising;
means for scanning the entire surface for the first position indicator; and
means for scanning the entire surface for the second position indicator; and
wherein the scan of the entire surface for the first position indicator and the scan of the entire surface for the second position indicator are repeated, and wherein the scan of the entire surface area for the first position indicator occurs more often than the scan of the entire surface area for the second position indicator. - View Dependent Claims (37)
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Specification