Touch-sensitive display device and method

• US 8,243,045 B2
• Filed: 03/10/2009
• Issued: 08/14/2012
• Est. Priority Date: 03/10/2009
• Status: Active Grant

• Current Assignee: Vibrant Licensing LLC (IP Edge LLC)
• Original Assignee: Empire Technology Development LLC (Allied Inventors Management, LLC)
• Inventors: Mangione-Smith, William Henry, Wolfe, Andrew, Conte, Thomas Martin
• Primary Examiner(s): Young, Wayne
• Assistant Examiner(s): BUTCHER, BRIAN M
• Application Number:
  US12/401,124
• Publication Number:
  US 20100231548A1
• Time in Patent Office: 1,253 Days
• Field of Search: None
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• 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: G09G 3/3258 with pixel circuitry controlling the voltage across the light-emitting element
• CPC Class Codes: H10K 59/40 OLEDs integrated with touch screens

Abstract

The present disclosure generally relates to a touch-sensitive LED display device with a number of shared circuits having measurement circuitry electrically coupled to display circuitry. A processor receives signals from the measurement circuitry and may compare the signals to determine a location of the touch on the touch screen.

Claims

1. A device that is responsive to a touch from a user, the device comprising:

a display comprising a plurality of touch-sensitive locations;

measurement circuitry electrically coupled to both the display and to each of the plurality of touch-sensitive locations, wherein each of the touch-sensitive locations affected by the touch generates a respective signal change having a magnitude corresponding to a strength of the touch in its respective associated measurement circuitry; and

a processor coupled to the measurement circuitry, wherein the processor is configured to receive a plurality of respective signal changes from the measurement circuitry corresponding to a plurality of the touch-sensitive locations affected by the touch, and wherein the processor is further configured to determine a location of the touch by identifying one or more touch-sensitive locations of the plurality of the touch-sensitive locations affected by the touch where the respective signal change has a highest magnitude.

2. The device of claim 1, wherein the display comprises an organic LED (OLED) display.

3. The device of claim 2, wherein the plurality of touch-sensitive locations comprise OLED pixels.

4. The device of claim 1, wherein the display comprises a capacitive touch-sensitive display.

5. The device of claim 1, further comprising drive circuitry configured to provide a plurality of sub-threshold signals to the display, wherein when the plurality of sub-threshold signals are provided to the display, a sub-threshold signal reference point is provided at each of the plurality of touch-sensitive locations, wherein the sub-threshold signals associated with each of the touch-sensitive locations affected by the touch are distorted in response to the touch proximate to the corresponding touch-sensitive locations.

6. The device of claim 5, wherein the measurement circuitry is configured to sense distortion in sub-threshold signals for each of the touch-sensitive locations affected by the touch.

7. The device of claim 1, wherein the processor is further configured to:

determine a central portion of the touch by identifying an area of the display substantially affected by the touch; and

compare the relative strengths of the signal changes at the location of the touch and the central point of the touch to identify an intended position of the touch.

8. The device of claim 1, wherein each of the plurality of touch-sensitive locations comprise a node, the node comprising an intersection of a row and a column of the touch-sensitive display.

9. The device of claim 8, wherein the touch-sensitive display row comprises a first layer and the touch-sensitive display column comprises a second layer, and the first and second layers are conductive and have an opposite charge when provided with a sub-threshold signal.

10. The device of claim 1, further comprising display circuitry, wherein the display circuitry is electrically coupled to the measurement circuitry and the electrically coupled display and measurement circuitry comprises a shared circuit.

11. The device of claim 10, wherein each of the plurality of touch-sensitive locations is associated with one shared circuit.

12. The device of claim 10, wherein the display comprises an organic LED (OLED) display and the display circuitry in the plurality of shared circuits comprises:

a first OLED display layer comprising a plurality of columns;

a second OLED display layer comprising a plurality of rows; and

a plurality of display nodes corresponding to a plurality of intersecting areas of the plurality of columns and rows, the display nodes comprising the plurality of touch-sensitive locations; and

measurement circuitry electrically coupled to each of the plurality of display nodes for each of the plurality of shared circuits.

13. A device that is responsive to a touch from a user when powered by a voltage from a power supply, the device comprising:

an OLED pixel electrically coupled to a measurement circuitry, wherein the OLED pixel is configured to emit light responsive to a first voltage exceeding an illumination threshold for the OLED pixel, and wherein the OLED pixel is also configured to provide signals to the measurement circuitry in response to the touch responsive to a second voltage less than the illumination threshold, and wherein the measurement circuitry is configured, responsive to a touch of the OLED pixel, to provide a signal having a magnitude corresponding to a strength of the touch such that the signal has a first magnitude responsive to the touch having a first strength and a second magnitude responsive to the touch having a second strength different from the first strength.

14. The device of claim 13, wherein the OLED pixel is arranged to generate a capacitance field at the OLED pixel when the voltage from the power supply fails to exceed the illumination threshold.

15. The device of claim 14, wherein the capacitance field at the OLED pixel is distorted in response the touch, and wherein the measurement circuitry senses the distortion in the capacitance field.

19. The device of claim 13, further comprising drive circuitry configured to provide the second voltage and a reference signal to the OLED pixel.

16. A method for determining a location of a touch on a touch-sensitive display, wherein the display includes a plurality of touch-sensitive locations, the method comprising:

coupling power to one or more of the plurality of touch-sensitive locations in the display;

generating individual charges at each of the plurality of touch-sensitive locations in the display when power is coupled thereto, wherein generating individual charges comprises providing sub-threshold signals to the display at the plurality of touch-sensitive locations;

monitoring the individual charges at each of the plurality of touch-sensitive locations in the display with a corresponding measurement circuit, wherein the corresponding measurement circuit is configured to provide a signal having a magnitude corresponding to a strength of the touch; and

identifying a change, responsive to a touch, in a plurality of the monitored individual charges to identify the location of the touch on the touch-sensitive display by identifying a location associated with a highest magnitude change of the plurality of monitored individual charges.

17. The method claim 16, wherein identifying the change in one or more of the monitored individual charges comprises identifying a distortion in one or more of the sub-threshold signals in response to a touch proximate to the one or more touch-sensitive locations.

18. The method of claim 16, wherein identifying the change in one or more of the monitored individual charges comprises:

receiving a signal corresponding to a change in the monitored individual charges for each of the touch-sensitive locations affected by the touch; and

determining a location of the touch by identifying one or more touch-sensitive locations having a highest degree of change in the monitored individual charge.