POINTER, POSITION DETECTION APPARATUS AND POSITION DETECTION METHOD

• US 20180173332A1
• Filed: 02/14/2018
• Published: 06/21/2018
• 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
• Granted Patent: US 10,514,781 B2
• Time in Patent Office: 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; and

a signal production circuit including a first node configured to output a first signal and a second node configured to output a second signal distinguishable from the first signal,

wherein,

the first node is coupled to the first electrode to transmit the first signal from the first electrode,

the second node is selectively coupled to and uncoupled from the second electrode to transmit or not transmit the second signal from the second electrode, and

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

2. The pen-shaped position indicator according to claim 1, wherein the second electrode is arranged to surround the first electrode.

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

4. The pen-shaped position indicator according to claim 1, wherein the first electrode is arranged on the axis of the pen-shaped position indicator.

5. The pen-shaped position indicator according to claim 1, wherein the pen-tip portion includes conductive material and forms the first electrode.

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

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

8. A method of detecting angular information of a pen-shaped position indicator including a first electrode arranged at a first distal position of the pen-shaped position indicator and a second electrode positioned at a second distal position different from the first distal position, the second distal position being off an axis of the pen-shaped position indicator, the method comprising:

in a signal production circuit of the pen-shaped position indicator including a first node configured to output a first signal and a second node configured to output a second signal distinguishable from the first signal, coupling the first node to the first electrode to transmit the first signal from the first electrode, and selectively coupling and uncoupling the second node to and from the second electrode to transmit or not transmit the second signal from the second electrode,

forming a first capacitive relationship between a sensor surface and the first electrode transmitting the first signal and a second capacitive relationship between the sensor surface and the second electrode transmitting the second signal, and

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

9. The method according to claim 8, wherein the second electrode is arranged to surround the first electrode.

10. The method according to claim 8, wherein the second electrode consists of plural electrode pieces arranged to surround the first electrode.

11. The method according to claim 8, wherein the first electrode is arranged on the axis of the pen-shaped position indicator.

12. The method according to claim 8, wherein the first and second signals are different in signal-type from each other.

13. The method according to claim 8, wherein the first and second signals are of the same signal-type but have a time difference from each other.

14. 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; and

a signal production circuit including a ground, a first node configured to supply a first signal, and a second node configured to supply a second signal distinguishable from the first signal, wherein;

when the first node of the signal production circuit is coupled to the first electrode to transmit the first signal from the first electrode, the ground of the signal production circuit is not connected to the second electrode, and

when the second node of the signal production circuit is coupled to the second electrode to transmit the second signal from the second electrode, the ground of the signal production circuit is not connected to the first electrode,

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

15. The pen-shaped position indicator according to claim 14, wherein the second electrodes at the pen-tip portion is arranged to surround the axis of the pen-shaped position indicator.

16. A method of detecting angular information of a pen-shaped position indicator including a first electrode arranged at a first distal position of the pen-shaped position indicator and a second electrode positioned at a second distal position different from the first distal position, the second distal position being off an axis of the pen-shaped position indicator, the method comprising:

in a signal production circuit of the pen-shaped position indicator including a ground, a first node configured to output a first signal, and a second node configured to output a second signal distinguishable from the first signal, coupling the first node to the first electrode to transmit the first signal from the first electrode while not coupling the ground to the second electrode, and coupling the second node to the second electrode to transmit the second signal from the second electrode while not coupling the ground to the first electrode,

forming a first capacitive relationship between a sensor surface and the first electrode transmitting the first signal and a second capacitive relationship between the sensor surface and the second electrode, and

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

17. The method according to claim 16, wherein the second electrode is arranged to surround the first electrode.

18. The method according to claim 16, wherein the second electrode consists of plural electrode pieces arranged to surround the first electrode.

19. The method according to claim 16, wherein the first electrode is arranged on the axis of the pen-shaped position indicator.

20. The method according to claim 16, wherein the pen-tip portion includes conductive material and forms the first electrode.