TOUCH SCREEN LIQUID CRYSTAL DISPLAY

• US 20170147119A1
• Filed: 02/03/2017
• Published: 05/25/2017
• Est. Priority Date: 06/09/2006
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: HOTELLING, Steve Porter, den BOER, Willem, HODGE, Andrew Bert, CHEN, Wei, KRAH, Christoph H., ELIAS, John Greer, YAO, Wei Hsin, ZHONG, John Z., LAND, Brian R.
• Granted Patent: US 10,191,576 B2
• Time in Patent Office: Days
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 2201/124 interdigital
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• CPC Class Codes: G06F 2203/04112 Electrode mesh in capacitive digitiser: electrode for touch sensing is formed of a mesh of very fine, normally metallic, interconnected lines that are almost invisible to see. This provides a quite large but transparent electrode surface, without need for ITO or similar transparent conductive material
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• 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 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0444 using a single conductive element covering the whole sensing surface, e.g. by sensing the electrical current flowing at the corners
• 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 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2300/0439 : Pixel structures
• CPC Class Codes: G09G 2300/0456 : with a reflective area and a transmissive area combined in one pixel, such as in transflectance pixels
• CPC Class Codes: G09G 2300/0478 : related to liquid crystal pixels
• CPC Class Codes: G09G 2310/0205 : Simultaneous scanning of several lines in flat panels
• CPC Class Codes: G09G 3/3614 : Control of polarity reversal in general
• CPC Class Codes: G09G 3/3648 : using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

Disclosed herein are liquid-crystal display (LCD) touch screens that integrate the touch sensing elements with the display circuitry. The integration may take a variety of forms. Touch sensing elements can be completely implemented within the LCD stackup but outside the not between the color filter plate and the array plate. Alternatively, some touch sensing elements can be between the color filter and array plates with other touch sensing elements not between the plates. In another alternative, all touch sensing elements can be between the color filter and array plates. The latter alternative can include both conventional and in-plane-switching (IPS) LCDs. In some forms, one or more display structures can also have a touch sensing function. Techniques for manufacturing and operating such displays, as well as various devices embodying such displays are also disclosed.

Claims

1. A touch screen comprising a display with integral touch sensing, the touch screen comprises:

a first plurality of pixels, each having first and second electrodes, a common terminal of the first plurality of pixels electrically connected together along a first direction;

a second plurality of pixels each having first and second electrodes, a common terminal of the second plurality of pixels electrically connected together along a second direction;

a plurality of data line for transmitting display data; and

a plurality of switches, operative in a display mode of operation, for connecting the plurality of data lines to the first electrodes of the first plurality of pixels and the first electrodes of the second plurality of pixels;

a first group of the first plurality of pixels;

a first group of the second plurality of pixels disposed adjacent the first group of the first plurality of pixels;

a second group of first plurality of pixels adjacent the first group of the second plurality of pixels; and

a second group of the second plurality of pixels adjacent the second group of the first plurality of pixels;

wherein the common terminals of the first and second groups of the second plurality of pixels are connected together along conductors disposed crossing the first plurality of pixels while electrically bypassing the first plurality of pixels.

2. The touch screen of claim 1, wherein at least one of the first and second electrodes of the first plurality of pixels and at least one of the first and second electrodes of the second plurality of pixels are used both for display of data from the plurality of data lines during the display mode of operation and for touch sensing during a touch sensing mode of operation.

3. The touch screen of claim 2, wherein the first and second electrodes of the first and second plurality of pixels are disposed in an in-plain-switching configuration.

4. The touch screen of claim 3, wherein the common terminals of the first plurality of pixels are connected to the second electrodes of the first plurality of pixels, and the common terminals of the second plurality of pixels are connected to the second electrodes of the second plurality of pixels.

5. The touch screen of claim 4, wherein during the touch sensing mode of operation, the second electrodes of the first plurality of pixels is adapted for receiving a stimulation signal and the second electrodes of the second plurality of pixels is adapted for connection to touch sensing circuitry.

6. The touch screen of claim 1, further comprising:

a first polarizer;

a second polarizer;

a first substrate disposed between the first polarizer and the second polarizer;

a second substrate disposed between the first polarizer and the second polarizer;

the first and second electrodes of the first plurality of pixels and the first and second electrodes of the second plurality of pixels disposed on the first substrate on a side thereof facing the second substrate.

7. The touch screen of claim 1, wherein the first direction is one of a row or a column and the second direction is the other of the row or column, and wherein the conductors are disposed along one of a row or column.

8. The touch screen of claim 1, wherein the second electrodes of the first plurality of pixels and the second electrode of the second plurality of pixels are capacitively coupled during a touch sensing mode of operation.

9. The touch screen of claim 8, wherein the first and second electrodes of the first and second plurality of pixels are disposed in an in-plain-switching configuration.

10. The touch screen of claim 9, wherein during the touch sensing mode of operation, the second electrodes of the first plurality of pixels is adapted for receiving a stimulation signal and the second electrodes of the second plurality of pixels is adapted for connection to touch sensing circuitry.

11. The touch screen of claim 1, wherein during the touch sensing mode of operation, the second electrodes of the first plurality of pixels is adapted for receiving a stimulation signal and the second electrodes of the second plurality of pixels is adapted for connection to touch sensing circuitry.

12. The touch screen of claim 1, wherein the display comprises a liquid crystal display.

13. The touch screen of claim 6, wherein the display comprises a liquid crystal display.

14. The touch screen of claim 1, wherein the first and second electrodes of the first and second plurality of pixels comprises interdigitated pairs of electrodes.

15. The touch screen of claim 6, wherein the first and second electrodes of the first and second plurality of pixels comprises interdigitated pairs of electrodes.

16. The touch screen of claim 1, wherein the first group of the first plurality of pixels and the second group of the first plurality of pixels comprises pixels disposed along the first and second directions.

17. The touch screen of claim 6, wherein the first group of the first plurality of pixels and the second group of the first plurality of pixels comprises pixels disposed along the first and second directions.

18. The touch screen of claim 1, wherein the first group of the first plurality of pixels and the second group of the first plurality of pixels and the second group of the second plurality of pixels and the second group of the second plurality of pixels first comprises pixels disposed along the first and second directions.

19. The touch screen of claim 18, wherein the display comprises a liquid crystal display.

20. The touch screen of claim 6, wherein the second electrodes of the first plurality of pixels and the second electrode of the second plurality of pixels are capacitively coupled during a touch sensing mode of operation.

21. The touch screen of claim 6, wherein the first group of the first plurality of pixels and the second group of the first plurality of pixels and the second group of the second plurality of pixels and the second group of the second plurality of pixels first comprises pixels disposed along the first and second directions.

22. A method of operating the touch screen of claim 1, comprising:

alternately applying a stimulation signal to the second electrodes of the first and second plurality of pixels; and

alternately coupling a capacitance sensing circuitry to the second electrodes of the second and first plurality of pixels.

23. A method of operating the touch screen of claim 6, comprising:

alternately applying a stimulation signal to the second electrodes of the first and second plurality of pixels; and

alternately coupling a capacitance sensing circuitry to the second electrodes of the second and first plurality of pixels.