ON-CELL TOUCH ARCHITECTURE

• US 20150169121A1
• Filed: 04/18/2014
• Published: 06/18/2015
• Est. Priority Date: 12/13/2013
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Yao, Weijun, Yao, Wei Hsin, Li, Yingxuan, Bae, Hopil, Al-Dahle, Ahmad
• Granted Patent: US 10,691,235 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• 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 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer

Abstract

Integrated touch screens are provided including drive lines formed of grouped-together circuit elements of a thin film transistor layer and sense lines formed between a color filter layer and a material layer that modifies or generates light. The common electrodes (Vcom) in the TFT layer can be grouped together during a touch sensing operation to form drive lines. Sense lines can be formed on a separate layer dedicated to only touch hardware.

Claims

1. A touch sensitive device including a plurality of display pixels, the touch sensitive device comprising:

a color filter layer;

a first ITO layer, the first ITO layer containing circuit elements that can be configured to operate as both touch hardware and display hardware;

a TFT layer;

a liquid crystal layer disposed between the TFT layer and the color filter layer; and

a second ITO layer, the second ITO layer disposed above the color filter layer.

2. The touch sensitive device of claim 1, wherein the first ITO layer is configured to act as drive lines in a mutual capacitance touch sensor during a touch mode of the device.

3. The touch sensitive device of claim 2, wherein the drive lines of the first ITO layer are stimulated with signals that are based on the elements of a matrix stored in a memory of the touch sensitive device.

4. The touch sensitive device of claim 3, wherein the matrix is a Hadamard matrix.

5. The touch sensitive device of claim 3, wherein the matrix is a circulant matrix.

6. The touch sensitive device of claim 3, wherein the matrix is an identity matrix.

7. The touch sensitive device of claim 1, wherein the first ITO layer can be configured to act as display electrodes during a display mode of the device.

8. The touch sensitive device of claim 1, wherein the first ITO layer can switchably operate as display circuitry during a display mode of the device, and as touch circuitry during a touch mode of the device, and wherein the display and touch modes are time multiplexed.

18. The touch sensitive device of claim 2, wherein the drive lines are arranged in vertical columns, while a plurality of sense lines of the device are arranged in horizontal rows.

9. An organic light emitting diode touch sensitive device including a plurality of display pixels, the device comprising:

an encapsulation layer;

a cathode layer, the cathode layer containing circuit elements that can be configured to operate as both touch hardware and display hardware; and

an ITO layer, the ITO layer disposed above the encapsulation layer.

10. The touch sensitive device of claim 9, wherein the cathode layer is configured to act as sense lines in a mutual capacitance touch sensor during a touch mode of the device.

11. The touch sensitive device of claim 9, wherein the ITO layer is configured to act as drive lines in a mutual capacitance touch sensor during a touch mode of the device.

12. The touch sensitive device of claim 11, wherein the drive lines of the ITO layer are stimulated with signals that are based on the elements of a matrix stored in a memory of the touch sensitive device.

13. The touch sensitive device of claim 12, wherein the matrix is a Hadamard matrix.

14. The touch sensitive device of claim 12, wherein the matrix is a circulant matrix.

15. The touch sensitive device of claim 12, wherein the matrix is an identity matrix.

16. The touch sensitive device of claim 9, wherein the cathode layer is configured to act as cathodes in an OLED display during a display mode of the device.

17. The touch sensitive device of claim 9, wherein the cathode layer can switchably operate as display circuitry during a display mode of the device, and as touch circuitry during a touch mode of the device, and wherein the display and touch modes are time multiplexed.

19. The touch sensitive device of claim 11, wherein the drive lines are arranged in vertical columns, while a plurality of sense lines of the device are arranged in horizontal rows.