Apparatus, method, and medium for sensing movement of fingers using multi-touch sensor array

• US 20070268269A1
• Filed: 03/22/2007
• Published: 11/22/2007
• Est. Priority Date: 05/17/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Chang, Wook, Park, Joon-ah, Cho, Seong-il, Soh, Byung-seok
• Granted Patent: US 9,274,652 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0485 Scrolling or panning

Abstract

A sensing technique using a capacitance touch sensor as a user interface is provided. An apparatus for sensing the movement of fingers using a multi-touch sensor includes a touch determination module which determines whether a user has actually touched a touch sensor comprising one or more touch points with at least one of his/her fingers, a clustering module which groups a plurality of electrodes arrayed in the touch sensor into one or more clusters according to a set of standards if the touch determination module determines that the user has actually touched the touch sensor with at least one of his/her finger, a position value calculation module which calculates a finger position value indicating the location of the finger of the user that touches the touch sensor for each of the clusters, and a movement information detection module which detects movement information of the finger of the user that touches the touch sensor using information regarding variations over time in the finger position value.

Claims

1. An apparatus for sensing a movement of at least one finger, the apparatus comprising:

a touch determination module which determines whether a user has actually touched a touch sensor comprising one or more touch points with at least one finger;

a clustering module which groups a plurality of electrodes arrayed in the touch sensor into one or more clusters if the touch determination module determines that the user has actually touched the touch sensor with at least one finger;

a position value calculation module which calculates a finger position value indicating the location of the at least one finger of the user that touches the touch sensor for each of the clusters; and

a movement information detection module which detects movement information of the at least one finger of the user that touches the touch sensor using information regarding variations over time in the finger position value.

2. The apparatus of claim 1 further comprising a touch sensor integrated circuit (IC) which calculates capacitance generated when the user touches the touch sensor with the at least one finger, digitizes the result of the calculation, outputs a signal obtained by the digitization, and measures the output signal.

3. The apparatus of claim 2, wherein the touch determination module determines that the user has actually touched the touch sensor with at least one finger if the standard deviation of the measured signal is larger than a predefined threshold.

4. The apparatus of claim 1, wherein the electrodes are grouped into one or more clusters based on the number of electrodes arrayed in the touch sensor, the sum of the intensities of digital signals respectively output by the electrodes of the touch sensor, or the combination thereof.

5. The apparatus of claim 1, wherein the position value calculation module calculates the finger position value by applying a weighted average to each of the clusters.

6. The apparatus of claim 5, wherein the position value calculation module determines displacement between a current finger position value and a previous finger position value using the finger position value.

7. The apparatus of claim 6, wherein the displacement between the current finger position value and the previous finger position value can be determined as indicated by the following equation:

D_ij=Pc_j(t-1)−

Pc_j(t) or D_ji=Pc_j(t)−

Pc_i(t-1) where Pc_j(t) indicates a j-th finger position value of N finger position values detected at a current time t, and Pc_i(t-1) indicates an i-th finger position value of M finer position values detected at a previous time (t-1),

wherein the displacement between the current finger position value and the previous finger position value can be represented by an M*N matrix or an N*M matrix having D_ij or D_ji as an element.

8. The apparatus of claim 7, wherein the movement information detection module compares the j-th finger position value Pcj(t) detected at the current time t with the first through M-th finger position values Pc₁(t-1) through Pc_M(t-1) detected at the previous time (t-1), and determines whichever of the first through M-th finger position values Pc₁(t-1) through Pc_M(t-1) is least distant from the j-t-h finger position value Pcj(t) as displacement corresponding to movement of a j-th finger of the user.

9. The apparatus of claim 8, wherein the movement information detection module extracts information regarding intentional touches by the at least one finger using the displacement determined by the movement information detection module.

10. The apparatus of claim 9, wherein the information regarding intentional touches by the at least one finger comprises the number of at least one finger that intentionally touch the touch sensor and the number of the at least one finger that are moving on the touch sensor.

11. A method of sensing a movement of at least one finger, the method comprising:

(a) determining whether a user has actually touched a touch sensor comprising one or more touch points with at least one finger;

(b) grouping a plurality of electrodes arrayed in the touch sensor into one or more clusters if it is determined in (a) that the user has actually touched the touch sensor with at least one finger;

(c) calculating a finger position value indicating the location of the at least one finger of the user that touches the touch sensor for each of the clusters; and

(d) detecting movement information of the at least one finger of the user that touches the touch sensor using information regarding variations over time in the finger position value.

12. The method of claim 11, wherein (a) comprises calculating capacitance generated when the user touches the touch sensor with the at least one finger, digitizing the result of the calculation, outputting a signal obtained by the digitization, and measuring the output signal.

13. The method of claim 12, wherein (a) further comprises determining that the user has actually touched the touch sensor with at least one finger if the standard deviation of the measured signal is larger than a predefined threshold.

14. The method of claim 11, wherein the electrodes are grouped into one or more clusters based on the number of electrodes arrayed in the touch sensor, the sum of the intensities of digital signals respectively output by the electrodes of the touch sensor, or the combination thereof.

15. The method of claim 11, wherein (c) comprises calculating the finger position value by applying a weighted average to each of the clusters.

16. The method of claim 15, wherein (c) further comprises determining displacement between a current finger position value and a previous finger position value using the finger position value.

17. The method of claim 16, wherein the displacement between the current finger position value and the previous finger position value can be determined as indicated by the following equation:

D_ij=Pcj(t-1)−

Pcj(t) or D_ji=Pcj(t)−

Pci(t-1) where Pcj(t) indicates a j-th finger position value of N finger position values detected at a current time t, and Pci(t-1) indicates an i-th finger position value of M finer position values detected at a previous time (t-1),

wherein the displacement between the current finger position value and the previous finger position value can be represented by an M*N matrix or an N*M matrix having D_ij or D_ji as an element.

18. The method of claim 17, wherein (d) comprises:

(d1) the j-th finger position value Pcj(t) detected at the current time t with the first through M-th finger position values Pc₁(t-1) through Pc_M(t-1) detected at the previous time (t-1), and determining whichever of the first through M-th finger position values Pc₁(t-1) through Pc_M(t-1) is least distant from the j-th finger position value Pcj(t) as displacement corresponding to movement of a j-th finger of the user; and

(d2) filtering out unintentional touches by the user'"'"'s fingers by extracting information regarding intentional touches by the at least one finger using the displacement determined in (d1).

19. The method of claim 18, wherein the information regarding intentional touches by the at least one finger comprises the number of at least one finger that intentionally touch the touch sensor and the number of at least one finger that are moving on the touch sensor.

20. At least one computer readable medium storing computer readable instructions that control at least one processor to implement the method of claim 11.

21. An apparatus for sensing a movement of fingers, the apparatus comprising:

a touch determination module which determines whether a user has touched a touch sensor comprising one or more touch points with at least one finger;

a clustering module which groups a plurality of electrodes arrayed in a touch sensor into one or more clusters if the user has actually touched the touch sensor with at least one finger,

wherein the electrodes are grouped into one or clusters based on the number of electrodes arrayed in the touch sensor, the sum of the intensities of digital signals respectively output by the electrodes of the touch sensor, or a combination thereof;

a position value calculation module which calculates a finger position value indicating the location of the at least one finger of the user that touches the touch sensor for each of the clusters; and

a movement information detection module which detects movement information of the at least one finger of the user that touches the touch sensor based on variations over time in the finger position value.

22. A method of sensing a movement of at least one finger, the method comprising:

(a) grouping a plurality of electrodes arrayed in a touch sensor into one or more clusters when a user has actually touched the touch sensor with at least one finger,

wherein the electrodes are grouped into one or clusters based on the number of electrodes arrayed in the touch sensor, the sum of the intensities of digital signals respectively output by the electrodes of the touch sensor, or a combination thereof;

(b) calculating a finger position value indicating the location of the at least one finger of the user that touches the touch sensor for each of the clusters; and

(c) detecting movement information of the at least one finger of the user that touches the touch sensor based on variations over time in the finger position value.

23. At least one computer readable medium storing computer readable instructions that control at least one processor to implement the method of claim 22.