Touch screen device and method for driving thereof, and portable electronic device comprising the same

• US 9,524,070 B2
• Filed: 07/14/2015
• Issued: 12/20/2016
• Est. Priority Date: 03/23/2015
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Hwang, Jong Hee, Cho, Sung Yong
• Primary Examiner(s): Nguyen, Jimmy H
• Application Number:
  US14/798,979
• Publication Number:
  US 20160282999A1
• Time in Patent Office: 525 Days
• Field of Search: 345/174, 178/6, 178/5, 178/18.05, 178/18.06, 349/12
• US Class Current: 1/1
• CPC Class Codes: G01L 5/228 using tactile array force sensors
• CPC Class Codes: G01L 7/024 with mechanical transmitting or indicating means G01L7/043, G01L7/063, G01L7/084, G01L7/104, G01L7/166, G01L7/185 take precedence
• CPC Class Codes: G01L 9/0002 using variations in ohmic resistance G01L9/0051 takes precedence
• CPC Class Codes: G01L 9/0005 using variations in capacitance G01L9/0072 takes precedence
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• 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: G06F 3/0447 Position sensing using the local deformation of sensor cells

Abstract

Disclosed is a touch screen device that may include first and second substrates; a plurality of first electrode lines and a plurality of second electrode lines on the first substrate that cross each other to define a plurality of touch sensors, each touch sensor including first and second electrodes, and an elastic resistor, with a gap space between the second electrode and the elastic resistor; and a touch driver that is electrically connected to at least one of the plurality of first electrode lines and the plurality of second electrode lines, and that determines a two-dimensional or three-dimensional touch information depending on an amount of force that is applied to the touch screen device.

Claims

1. A touch screen device comprising:

first and second substrates;

a plurality of first electrode lines crossing a plurality of second electrode lines to define a plurality of touch sensors between the first and second substrates, each touch sensor including first and second electrodes, and an elastic resistor, with a gap space between the second electrode and the elastic resistor;

a touch driver that is electrically connected to the plurality of first electrode lines and the plurality of second electrode lines, and that determines a two-dimensional touch information based on a change of capacitance between the first electrode and the second electrode or a three-dimensional touch information based on a change of resistance between the first electrode and the second electrode, depending on an amount of force that is applied to the touch screen device,

wherein the touch driver further comprises,

a memory that store a first sensing data on the change of capacitance; and

a touch control part that detects a touch force event by monitoring and comparing the stored first sensing data with a threshold value, and that changes a first logic state of an event detection signal for measuring the two-dimensional touch information to a second logic state of the event detection signal for measuring the three-dimensional information, when the touch force event is detected.

2. The touch screen device of claim 1, wherein the three-dimensional touch information is determined, when there is a distortion of capacitance caused by a contact between the second electrode and the elastic resistor for the at least one of the plurality of touch sensors that receives the force.

3. The touch screen device of claim 1, further comprising a cover glass on the second substrate and a display panel below the first substrate.

4. The touch screen device of claim 1, wherein a resistance value of the elastic resistor between the first and second electrodes decreases as the amount of force increases.

5. The touch screen device of claim 1, wherein the elastic resistor includes one of a pressure-sensitive material and a piezo-sensitive material.

6. The touch screen device of claim 1, further comprising a supporter on the second substrate to maintain the gap space,

wherein the supporter has a Young'"'"'s modulus equal to or less than 0.3 MPa, and transmittance equal to or greater than 80% of a total transmittance.

7. The touch screen device of claim 6, wherein the supporter includes a plurality of border patterns or a plurality of dot support patterns.

8. The touch screen device of claim 1, wherein a height of the gap space is in a range of 10 um to 150 μ

m.

9. The touch screen device of claim 1, wherein the plurality of first electrode lines are electrically connected with the touch driver and supplied with a touch driving pulse.

10. The touch screen device of claim 9, wherein the touch driver further includes first sensing unit and a second sensing unit.

11. The touch screen device of claim 10, wherein the touch driver further has a selecting unit that includes a plurality of demultiplexers, each demultiplexer having one input channel and the one input channel connected with one of the plurality of second electrode lines, a first output channel connected with the first sensing unit and a second output channel connected with the second sensing unit.

12. The touch screen device of claim 10, wherein the first sensing unit generates the first sensing data based on a change of capacitance for each touch sensor through the plurality of second electrode lines.

13. The touch screen device of claim 12, wherein the touch driver generates the event detection signal of the first or second logic based on the first sensing data.

14. The touch screen device of claim 13, wherein the event detection signal of the second logic is generated when the first sensing data indicates of a distortion of capacitance that is caused by a contact between the second electrode and the elastic resistor for each touch sensor.

15. The touch screen device of claim 14, wherein when the event detection signal of the second logic is generated, the second sensing unit generates a second sensing data based on a change of resistance for at least one of the plurality of touch sensors through the plurality of second electrode lines.

16. A method of driving a touch screen device having a plurality of touch sensors, each including first and second electrodes, and an elastic resistor, with a gap space between the second electrode and the elastic resistor, the method comprising:

providing a touch driving signal to the first electrode;

sensing a change of capacitance between the first and second electrodes for each touch sensor through the second electrode;

storing a first sensing data on the change of capacitance in a memory, detecting a touch force event based on monitoring and comparing the stored first sensing data with a threshold value; and

sensing a change of resistance between the first and second electrodes for at least one of the plurality of touch sensors based on a result of the detecting the touch force event,

wherein when the touch force event is detected, a first logic state of an event detection signal for measuring two-dimensional information is changed to a second logic state of the event detection signal for measuring three-dimensional information.

17. The method of claim 16, further comprising determining a level of touch force applied to the touch screen device based on a result of the sensing the change of resistance.

18. The method of claim 16, wherein the detecting the touch force event is based on determining whether there is a distortion of capacitance that is caused by a contact between the second electrode and the elastic resistor for each touch sensor.