Pointer, position detection apparatus and position detection method

• US 10,108,277 B2
• Filed: 02/18/2016
• Issued: 10/23/2018
• Est. Priority Date: 02/05/2010
• Status: Active Grant

• Current Assignee: Wacom Co Limited (Wacom)
• Original Assignee: Wacom Co Limited (Wacom)
• Inventors: Oda, Yasuo, Yamamoto, Sadao, Sugiyama, Yoshihisa
• Primary Examiner(s): Lu, William
• Application Number:
  US15/047,013
• Publication Number:
  US 20160162054A1
• Time in Patent Office: 978 Days
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device
• CPC Class Codes: G06F 3/04162 for exchanging data with external devices, e.g. smart pens, via the digitiser sensing hardware
• CPC Class Codes: G06F 3/0442 using active external devices, e.g. active pens, for transmitting changes in electrical potential to be received by the digitiser
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/046 by electromagnetic means

Abstract

A position detection apparatus of the electrostatic coupling type is provided, to detect not only a position of a pointer but also information other than the position information such as, for example, pointer pressure or side switch information. The pointer transmits two codes such that a pressure applied to a pen tip is associated with a time difference between the two codes. A position detector carries out a correlation matching operation between signals generated in reception conductors and correlation calculation codes corresponding to the two codes, to thereby detect a position on a sensor section pointed to by the pointer from a result of the correlation matching operation and based on at least one of the codes. The position detector further includes a pressure calculation circuit for detecting pressure applied to the pointer, which is associated with the time difference between the two codes, from the result of the correlation matching operation calculated by the correlation matching operation and based on the two codes.

Claims

1. A pen-shaped position indicator configured to capacitively couple with a sensor surface, the pen-shaped position indicator comprising:

a pen-shaped body having a pen-tip portion;

a first electrode arranged at a first position of the pen-tip portion;

a second electrode arranged at a second position of the pen-tip portion different from the first position, the second position being off an axis of the pen-shaped position indicator;

a signal production circuit configured to generate first and second signals that are distinguishable from each other; and

conductive lines extending between the signal production circuit and the first and second electrodes, respectively, wherein the first and second signals generated by the signal production circuit, in operation, are transmitted to the first and second electrodes via the conductive lines;

wherein the first and second electrodes are configured to form first and second capacitive relationships with the sensor surface, respectively, to generate detection signals in the sensor surface based on which angle information of the pen-shaped position indicator is obtainable.

2. The pen-shaped position indicator according to claim 1, wherein the first and second electrodes are arranged at the first and second positions that are different along the axis of the pen-shaped position indicator.

3. The pen-shaped position indicator according to claim 1, wherein the second electrode comprises plural electrode pieces arranged to surround the axis of the pen-shaped position indicator.

4. The pen-shaped position indicator according to claim 1, wherein the first and second electrodes are arranged to surround the axis of the penshaped position indicator.

5. The pen-shaped position indicator according to claim 1, wherein the angle information is a tilt angle of the pen-shaped position indicator relative to the sensor surface.

6. The pen-shaped position indicator according to claim 3, wherein the angle information is a rotation angle of the pen-shaped position indicator about the axis of the pen-shaped position indicator.

7. The pen-shaped position indicator according to claim 1, wherein the first and second signals are different in type from each other.

8. The pen-shaped position indicator according to claim 1, wherein the first and second signals are of the same type but have a time difference from each other.

9. The pen-shaped position indicator according to claim 1, further comprising:

a coil configured to receive an excitation signal; and

a power generation circuit configured to generate a drive voltage based on the excitation signal;

wherein the drive voltage is supplied to the signal production circuit to generate the first and second signals.

10. A pen-shaped position indicator configured to capacitively couple with a sensor surface, the pen-shaped position indicator comprising:

a pen-shaped body having a pen-tip portion;

first and second electrodes arranged near the pen-tip portion to surround an axis of the pen-shaped position indicator; and

a signal production circuit configured to generate first and second signals that are distinguishable from each other; and

conductive lines extending between the signal production circuit and the first and second electrodes, respectively, wherein the first and second signals generated by the signal production circuit, in operation, are transmitted to the first and second electrodes via the conductive lines;

wherein the first and second electrodes are configured to form first and second capacitive relationships with the sensor surface, respectively, to generate detection signals in the sensor surface based on which angle information of the penshaped position indicator is obtainable.

11. The pen-shaped position indicator according to claim 10, wherein the pen-tip portion includes a conductive pen tip, to which the signal production circuit transmits a signal via a conductive line.

12. The pen-shaped position indicator according to claim 10, wherein the angle information is a tilt angle of the pen-shaped position indicator relative to the sensor surface.

13. The pen-shaped position indicator according to claim 10, wherein the angle information is a rotation angle of the pen-shaped position indicator about the axis of the pen-shaped position indicator.

14. A method of detecting angle information of a penshaped position indicator, the method comprising:

forming a first capacitive relationship between a sensor surface and first electrode, which is arranged at a first position of a pen-tip portion of the pen-shaped position indicator and is supplied with a first signal generated by a signal production circuit and transmitted via a first conductive line in the pen-shaped position indicator;

forming a second capacitive relationship between the sensor surface and a second electrode, which is arranged at a second position of the pen-tip portion different from the first position and off an axis of the pen-shaped position indicator and is supplied with a second signal generated by the signal production circuit and transmitted via a second conductive line in the pen-shaped position indicator, wherein the second signal is distinguishable from the first signal; and

detecting angular information of the pen-shaped position indicator based on the first and second capacitive relationships.

15. The method according to claim 14, wherein the first and second electrodes are arranged at the first and second positions that are different along the axis of the pen-shaped position indicator.

16. The method according to claim 14, wherein the second electrode comprises plural electrode pieces arranged to surround the axis of the penshaped position indicator.

17. The method according to claim 14, wherein the first and second electrodes are arranged to surround the axis of the pen-shaped position indicator.

18. The method according to claim 14, wherein the angle information is a tilt angle of the pen-shaped position indicator relative to the sensor surface.

19. The method according to claim 16, wherein the angle information is a rotation angle of the pen-shaped position indicator about the axis of the pen-shaped position indicator.

20. The method according to claim 14, wherein the first and second signals are different in type from each other.

21. The method according to claim 14, wherein the first and second signals are of the same type but have a time difference from each other.

22. A method of detecting angle information of a penshaped position indicator, the method comprising:

forming first and second capacitive relationships between a sensor surface and first and second electrodes, respectively, wherein the first and second electrodes are arranged near a pen-tip portion of the pen-shaped position indicator to surround an axis of the pen-shaped indicator, and wherein the first and second electrodes are supplied with first and second signals generated by a signal production circuit via first and second lines, respectively, wherein the first and second signals are distinguishable from each other; and

detecting angular information of the pen-shaped position indicator based on the first and second capacitive relationships.

23. The method according to claim 22, comprising:

forming a capacitive relationship between the sensor surface and the pen-tip portion including a conductive pen tip, to which a signal is supplied from the signal production circuit.

24. The method according to claim 22, wherein the angle information is a tilt angle of the pen-shaped position indicator relative to the sensor surface.

25. The method according to claim 22, wherein the angle information is a rotation angle of the pen-shaped position indicator about the axis of the pen-shaped position indicator.