INPUT DEVICE

• US 20140210764A1
• Filed: 01/29/2013
• Published: 07/31/2014
• Est. Priority Date: 12/18/2009
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: SHEPELEV, Petr
• Granted Patent: US 9,606,676 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24
• 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 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

An input device comprises a first and second pluralities of capacitive sensor electrodes. The first plurality of capacitive sensor electrodes is oriented along a first axis, disposed in a first layer, and configured to update a display screen of the input device. The second plurality of capacitive sensor electrodes is oriented along a second axis that differs from the first axis. A display region of the display screen has a first dimension along the first axis and a second dimension the second axis. At least one sensor electrode of the first plurality of capacitive sensor electrodes extends fully across the first dimension of the display region. Individual sensor electrodes of the second plurality of capacitive sensor electrodes do not extend fully across the second dimension of the display region.

Claims

1. An input device comprising:

a first plurality of capacitive sensor electrodes oriented along a first axis, disposed in a first layer, and configured to update a display screen of said input device;

a second plurality of capacitive sensor electrodes oriented along a second axis that differs from said first axis; and

wherein a display region of said display screen has a first dimension along said first axis and a second dimension said second axis, wherein at least one sensor electrode of said first plurality of capacitive sensor electrodes extends fully across said first dimension of said display region, and wherein individual sensor electrodes of said second plurality of capacitive sensor electrodes do not extend fully across said second dimension of said display region.

2. The input device of claim 1, further comprising:

a processing system coupled with said first plurality of capacitive sensor electrodes and with said second plurality of capacitive sensor electrodes, said processing system configured to;

receive a first type of resulting signals from the said second plurality of capacitive sensor electrodes, said first type of resulting signal based on a transcapacitive coupling between said first plurality of capacitive sensor electrodes and said second plurality of capacitive sensor electrodes;

receive a second type of resulting signals from a first subset and a second subset of said second plurality of said capacitive sensor electrodes, the second type of resulting signal based on an absolute capacitive coupling; and

determine positional information of an input object along said second axis, with respect to a sensing region of said input device, said positional information along said second axis determined based on said second type of resulting signals from either said first subset or said second subset of said capacitive sensor electrodes.

3. The input device of claim 2, wherein said processing system is further configured to:

determine positional information of said input object along said first axis, with respect to said sensing region of said input device, said positional information along said first axis determined based on said second type of resulting signals from both said first subset and said second subset of said capacitive sensor electrodes.

4. The input device of claim 2, wherein said processing system is further configured to:

receive said second type of resulting signals from said first subset of said second plurality of capacitive sensor electrodes while driving said second subset of said second plurality of capacitive sensor electrodes with a substantially constant voltage.

5. The input device of claim 2, wherein said processing system is further configured to:

update said display screen of said input device using said first plurality of sensor electrodes.

6. The input device of claim 2, wherein said processing system is further configured to:

ohmically couple a sensor electrode of said first subset of said second plurality of capacitive sensor electrodes with a sensor electrode of said second subset of said second plurality of capacitive sensor electrodes.

7. The input device of claim 2, further comprising a switch configured for ohmically coupling a sensor electrode of said first subset of said second plurality of capacitive sensor electrodes with a sensor electrode of said second subset of said second plurality of capacitive sensor electrodes, said switch coupled with and controlled by said processing system.

8. The input device of claim 7, wherein said switch is disposed in a thin-film transistor (TFT) layer of said display screen of said input device.

9. The input device of claim 1, wherein at least one sensor electrode of said second plurality of capacitive sensor electrodes forms multiple crossings with a first line overlapping said display region and perpendicular to said second axis.

10. The input device of claim 9, wherein a second line overlapping said display region and perpendicular to said second axis forms less crossings with said at least one sensor electrode of said second plurality of capacitive sensor electrodes than said multiple crossings which are formed with said first line.

11. The input device of claim 1, wherein the length along said second axis of a first sensor electrode of said second plurality of capacitive sensor electrodes along is substantially greater than the length along said second axis of a second sensor electrode of said second plurality of capacitive sensor electrodes.

12. The input device of claim 1, wherein said first layer comprises a thin-film transistor (TFT) layer of said display screen.

13. The input device as recited in claim 1, wherein said second plurality of capacitive sensor electrodes is disposed in a second layer that differs from said first layer.

14. The input device as recited in claim 1, wherein said second plurality of capacitive sensor electrodes is disposed said first layer.

15. A processing system for an input device, said processing system comprising:

a first plurality of input/outputs configured to couple with a first plurality of capacitive sensor electrodes that are oriented along a first axis, the first plurality of capacitive sensor electrodes configured to update a display screen of said input device;

a second plurality of input/outputs configured to couple with a second plurality of capacitive sensor electrodes that are oriented along second axis that differs from said first axis; and

wherein said processing system configured to;

receive a first type of resulting signals from the said second plurality of capacitive sensor electrodes, said first type of resulting signal based on a transcapacitive coupling between said first plurality of capacitive sensor electrodes and said second plurality of capacitive sensor electrodes;

receive a second type of resulting signals from a first subset and a second subset of said second plurality of said capacitive sensor electrodes, the second type of resulting signal based on an absolute capacitive coupling; and

determine positional information of an input object along said second axis, with respect to a sensing region of said input device, said positional information along said second axis determined based on said second type of resulting signals from either said first subset or said second subset of said second plurality of capacitive sensor electrodes.

16. The processing system of claim 15, wherein said processing system is further configured to:

determine positional information of said input object along said first axis, with respect to said sensing region of said input device, said positional information along said first axis determined based on said second type of resulting signals from both said first subset and said second subset of said capacitive sensor electrodes.

17. The processing system of claim 15, wherein said processing system is further configured to:

receive said second type of resulting signals from said first subset of said second plurality of capacitive sensor electrodes while driving said second subset of said second plurality of capacitive sensor electrodes with a substantially constant voltage.

18. The processing system of claim 15, wherein said processing system is further configured to:

update said display screen of said input device using said first plurality of capacitive sensor electrodes.

19. The processing system of claim 15, wherein said processing system is further configured to:

ohmically couple a sensor electrode of said first subset of said second plurality of capacitive sensor electrodes with a sensor electrode of said second subset of said second plurality of capacitive sensor electrodes.

20. A method of operating an input device, wherein said method comprises:

determining first positional information related to input in a first sensing region of said input device by performing transcapacitive sensing using a first plurality of capacitive sensor electrodes and a second plurality of capacitive sensor electrodes,

wherein said first plurality of capacitive sensor electrodes is oriented along a first axis and disposed in a first layer, and

wherein said second plurality of capacitive sensor electrodes is oriented along a second axis that differs from said first axis and disposed in a second layer that differs from said first layer; and

determining positional information along said second axis, with respect to input in a second sensing region of said input device, said positional information along said second axis determined by performing absolute capacitive sensing using either a first subset or a second subset of said second plurality of capacitive sensing electrodes.

21. The method as recited in claim 20, further comprising:

determining positional information along said first axis, with respect to input in said second sensing region, said positional information along said first axis determined by performing absolute capacitive sensing using both said first subset and said second subset of said second plurality of capacitive sensing electrodes.

22. The method as recited in claim 20, further comprising:

updating a display screen with said first plurality of capacitive sensor electrodes, said display screen associated with said input device and overlapped by said first sensing region and said second sensing region.