Touch detection

• US 8,310,459 B2
• Filed: 09/23/2009
• Issued: 11/13/2012
• Est. Priority Date: 09/23/2009
• Status: Active Grant

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Corporation
• Inventors: Nurmi, Juha H-P
• Primary Examiner(s): Wong, K.
• Application Number:
  US12/565,472
• Publication Number:
  US 20110069015A1
• Time in Patent Office: 1,147 Days
• Field of Search: None
• US Class Current: 345/173
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• 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 3/047 using sets of wires, e.g. crossed wires
• CPC Class Codes: G06F 3/1423 controlling a plurality of local displays, e.g. CRT and flat panel display
• CPC Class Codes: G06F 3/1446 display composed of modules, e.g. video walls

Abstract

An apparatus with a first and second touch screen, where the first touch screen has a plurality of first touch sensors formed as a first grid of rows and columns and the second touch screen has a plurality of second touch sensors formed as a second grid of rows and columns. A first processor detects touch areas by scanning through the first touch sensors in a predetermined order along the rows and columns. A second processor detects touch areas by scanning through the second touch sensors in a predetermined order along the rows and columns. A controller causes that the first and second processors scan the first and second grids synchronized such that when the first and second touch screens are arranged side by side, neighboring first and second touch sensors are scanned substantially simultaneously.

Claims

1. An apparatus comprising:

a first touch screen comprising a plurality of first touch sensors formed as a first grid of rows and columns;

a second touch screen comprising a plurality of second touch sensors formed as a second grid of rows and columns;

a first processor configured to detect touch areas by scanning through the first touch sensors in a predetermined order along the rows and columns;

a second processor configured to detect touch areas by scanning through the second touch sensors in a predetermined order along the rows and columns; and

a controller configured to cause the first and second processors to scan the first and second grids synchronized such that when the first and second touch screens are arranged side by side so that at neighboring sides of the first and second grids there are neighboring rows of each touch screen adjacent to each other, the first and second touch sensors of neighboring rows are scanned substantially simultaneously.

2. An apparatus according to claim 1, wherein the first processor comprises the controller.

3. An apparatus according to claim 1, wherein the apparatus further comprises a third processor and the third processor comprises the controller.

4. An apparatus according to claim 3, wherein the third processor is configured to function as a baseband frequency signal processing engine.

5. An apparatus according to claim 1, wherein the apparatus further comprises a first display and a second display, wherein the first touch screen and the first display are stacked and wherein the second touch screen and second display are stacked.

6. An apparatus according to claim 1, the apparatus further comprising a first timing controller configured to select for touch detection one row at the time in the first grid of rows and columns.

7. An apparatus according to claim 6, the apparatus further comprising a second timing controller configured to select for touch detection one row at the time in the first grid of rows and columns.

8. An apparatus according to claim 6, wherein the first timing controller is further configured to select for touch detection one row at the time in the second grid of rows and columns.

9. An apparatus according to claim 1, wherein the apparatus further comprises a first read-out circuit configured to detect columns in the first grid indicative of touch at a crossing with a currently selected row of the first grid.

10. An apparatus according to claim 9, wherein the apparatus further comprises a second read-out circuit configured to detect columns in the second grid indicative of touch at a crossing with a currently selected row of the second grid.

11. A method in an apparatus comprising a first touch screen comprising a plurality of first touch sensors formed as a first grid of rows and columns;

and a second touch screen comprising a plurality of second touch sensors formed as a second grid of rows and columns;

the method comprising;

detecting touch areas by scanning through the first touch sensors in a predetermined order along the rows and columns;

detecting touch areas by scanning through the second touch sensors in a predetermined order along the rows and columns; and

causing first and second processors to scan the first and second grids synchronized such that when the first and second touch screens are arranged side by side so that at neighboring sides of the first and second grids there are neighboring rows of each touch screen adjacent to each other, the first and second touch sensors of neighboring rows are scanned substantially simultaneously.

12. A method according to claim 11, further comprising selecting by a first timing controller for touch detection one row at the time in the first grid of rows and columns.

13. A method according to claim 12, further comprising selecting by a second timing controller for touch detection one row at the time in the first grid of rows and columns.

14. A method according to claim 12, further comprising selecting by the first timing controller for touch detection one row at the time in the second grid of rows and columns.

15. A method according to claim 11, further comprising detecting by a first read-out circuit columns in the first grid indicative of touch at a crossing with a currently selected row of the first grid.

16. A method according to claim 15, further comprising detecting by a second read-out circuit columns in the second grid indicative of touch at a crossing with a currently selected row of the second grid.

17. An article of manufacture comprising a computer readable medium containing computer executable program code configured, when executed by a computer, to control an apparatus comprising a first touch screen with a plurality of first touch sensors formed as a first grid of rows and columns and a second touch screen with a plurality of second touch sensors formed as a second grid of rows and columns;

the controlling comprising causing the apparatus to;

detect touch areas by scanning through the first touch sensors in a predetermined order along the rows and columns;

detect touch areas by scanning through the second touch sensors in a predetermined order along the rows and columns; and

cause first and second processors to scan the first and second grids synchronized such that when the first and second touch screens are arranged side by side so that at neighboring sides of the first and second grids there are neighboring rows of each touch screen adjacent to each other, the first and second touch sensors of neighboring rows are scanned substantially simultaneously.

18. An article of manufacture according to claim 17, wherein the controlling further comprises causing the apparatus to select by a first timing controller for touch detection one row at the time in the first grid of rows and columns.

19. An article of manufacture according to claim 18, wherein the controlling further comprises causing the apparatus to select by a second timing controller for touch detection one row at the time in the first grid of rows and columns.

20. An article of manufacture according to claim 18, wherein the controlling further comprises causing the apparatus to select by the first timing controller for touch detection one row at the time in the second grid of rows and columns.