STYLUS PEN AND TOUCH PANEL

• US 20160216784A1
• Filed: 10/29/2015
• Published: 07/28/2016
• Est. Priority Date: 01/27/2015
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: KIM, Kang-nam, HAN, Se-hyun, KIM, Byung-jik
• Granted Patent: US 10,488,951 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 1/16 Constructional details or arrangements
• CPC Class Codes: G06F 3/03545 Pens or stylus
• 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 3/0441 using active external devices, e.g. active pens, for receiving changes in electrical potential transmitted by the digitiser, e.g. tablet driving signals
• 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

Abstract

A stylus pen and a touch panel are provided. The stylus pen includes: a conductive tip configured to receive an electric field transmission signal from at least one electrode of the touch panel; a circuit portion configured to generate an electric field receiving signal corresponding to the received electric field transmission signal; a variable capacitor between the conductive tip and the circuit portion, and configured to vary the electric field receiving signal depending on a writing pressure applied to the conductive tip; and a conductive body outside the variable capacitor and electrically connecting the conductive tip and the circuit portion.

Claims

1. A stylus pen for making an input to a position on a touch panel, the stylus pen comprising:

a conductive tip configured to receive an electric field transmission signal from at least one electrode of the touch panel;

a circuit portion configured to generate an electric field receiving signal corresponding to the received electric field transmission signal;

a variable capacitor between the conductive tip and the circuit portion, and configured to vary the electric field receiving signal depending on a writing pressure applied to the conductive tip; and

a conductive body outside the variable capacitor and electrically connecting the conductive tip and the circuit portion.

2. The stylus pen of claim 1, wherein the variable capacitor comprises:

a dielectric comprising a first surface and a second surface positioned opposite to the first surface;

a first electrode in contact with the first surface of the dielectric; and

a conductive variable electrode configured such that a contact area between the conductive variable electrode and the second surface of the dielectric is varied depending on a pressure applied through the conductive tip.

3. The stylus pen of claim 2, wherein the conductive variable electrode is configured such that a central portion of a surface in contact with the second surface of the dielectric is convex from an edge portion of the surface.

4. The stylus pen of claim 2, wherein the conductive variable electrode is configured such that a central portion of a surface in contact with the second surface of the dielectric is concave from an edge portion of the surface.

5. The stylus pen of claim 2, wherein the conductive variable electrode comprises a conductive rubber.

6. The stylus pen of claim 2, further comprising an elastic member in an inside of the conductive variable electrode.

7. The stylus pen of claim 1, further comprising a ground portion electrically connected to a user through at least one of direct contact and capacitive coupling.

8. The stylus pen of claim 7, further comprising a conductive case isolated from the conductive body and connected to the ground portion.

9. The stylus pen of claim 1, further comprising an elastic member configured to restore a position of the conductive tip.

10. The stylus pen of claim 9, further comprising:

a housing having a tubular shape and housing the variable capacitor,

wherein the housing is formed of a non-conductive material, and comprises at least one opening on an outer circumferential surface of the housing and through which the conductive body passes.

11. The stylus pen of claim 10, further comprising an insulator on an outer circumferential surface of the conductive tip, to isolate the conductive tip from the elastic member and the variable capacitor.

12. The stylus pen of claim 11, wherein:

the insulator comprises a first cap and a second cap; and

the first cap is on an end of the housing and supports a first end of the elastic member, and the second cap is on the outer circumferential surface of the conductive tip and supports a second end of the elastic member.

13. The stylus pen of claim 11, wherein the insulator comprises a guide member on the outer circumferential surface of the conductive tip and configured to guide the conductive tip in a lengthwise direction of the housing.

14. The stylus pen of claim 13, wherein the guide member supports a first end of the elastic member and a projection on an inner circumferential surface of the housing supports a second end of the elastic member.

15. The stylus pen of claim 9, wherein the elastic member comprises a non-conductive material.

16. The stylus pen of claim 9, further comprising:

a conductive support member comprising a first receiving hole in a first end of the conductive support member and a second receiving hole in a second end, opposite the first end, of the conductive support member,

wherein the first receiving hole is coupled with the conductive variable electrode, and

wherein the second receiving hole is coupled with an end portion of the conductive tip.

17. The stylus pen of claim 16, further comprising an insulator on an outer circumferential surface of the conductive support member to isolate the conductive support member from the elastic member.

18. The stylus pen of claim 1, wherein:

the conductive body comprises a plurality of plates and a circular member connected to an end of each of the plurality of plates;

the plurality of plates are spaced apart from each other and disposed side-by-side; and

the circular member comprises an opening through which the conductive tip passes.

19. The stylus pen of claim 1, wherein the circuit portion comprises:

a capacitor having a predetermined capacitance; and

a switch configured to allow the capacitor to be selectively connected in parallel to the variable capacitor.

20. The stylus pen of claim 1, wherein a first end of the variable capacitor is directly connected to an end of the circuit portion, and a second end of the variable capacitor is connected to the circuit portion through the conductive body.

21. A stylus pen comprises:

a conductive tip projecting from an end of the stylus pen;

a dielectric comprising a first surface and a second surface positioned opposite to the first surface;

a first electrode in contact with the first surface of the dielectric;

a conductive variable electrode configured such that a contact area between the conductive variable electrode and the second surface of the dielectric is varied depending on a pressure applied through the conductive tip; and

a conductive body outside the dielectric, electrically connecting the conductive tip and the conductive variable electrode, and isolated from the dielectric and the first electrode.

22. The stylus pen of claim 21, further comprising an elastic member isolated from the conductive tip and configured to restore a position of the conductive tip.

23. A touch panel for determining an input position of an input object, the touch panel comprising:

at least one electrode; and

a controller configured to control an electric field transmission signal generated in the at least one electrode to be transmitted to the input object, and to control to receive, from the input object via the at least one electrode, an electric field receiving signal corresponding to the electric field transmission signal.

24. The touch panel of claim 23, wherein the controller is configured to determine the input position and a pressure of the input object to the touch panel, based on the received electric field receiving signal.

25. The touch panel of claim 23, further comprising:

a driver configured to control the electric field transmission signal to be transmitted from the at least one electrode, according to a control of the controller; and

a receiver configured to receive the electric field receiving signal via the at least one electrode,

wherein the controller is configured to control the driver and the receiver to alternately operate.