Touchscreen display device and related method

Patent metadata

Field	Value
Publication number	US-9052770-B2
Application number	US-201313737676-A
Country	US
Kind code	B2
Filing date	Jan 9, 2013
Priority date	Aug 24, 2012
Publication date	Jun 9, 2015
Grant date	Jun 9, 2015

Abstract

A display device includes a display element. The display device may include a touch substrate overlapping the display element and may overlap an external object when the external object provides a touch to the display device. The display device may include a first angle sensor disposed at a first corner of the touch substrate for determining a first touch angle related to the touch. The display device may include a second angle sensor disposed at a second corner of the touch substrate for determining a second touch angle related to the touch. The display device may include a force sensor disposed at the first corner of the touch substrate for determining a distance related to the touch. The display device may include a computation part configured to determine a touch coordinate associated with the touch based on the first touch angle, the second touch angle, and the distance.

First claim

What is claimed is:

1. A display device, comprising:
a display element configured to display images;
a touch substrate at which a touch is generated, wherein the touch substrate overlaps the display element;
a first angle sensor disposed at a first corner of the touch substrate for determining a first touch angle related to the touch;
a second angle sensor disposed at a second corner of the touch substrate for determining a second touch angle related to the touch;
a force sensor disposed at the first corner of the touch substrate corresponding to the first angle sensor for determining a distance from the force sensor to the touch; and
a computation part configured to determine a touch coordinate associated with the touch based on the first touch angle determined by the first angle sensor, the second touch angle determined by the second angle sensor, and the distance determined by the force sensor.

2. The display device of claim 1 , wherein the force sensor is further configured to calculate a magnitude of a sensor force received at the force sensor, and wherein at least one of the force sensor and the computation part is further configured to calculate a magnitude of a touch force received at the touch point and related to the touch based on the distance and the sensor force.

3. The display device of claim 1 , wherein the first angle sensor includes an infrared camera, and
wherein the infrared camera comprises a light output portion for outputting an output infrared light and a light input portion for receiving a reflected infrared light that is resulted from the output infrared light.

4. The display device of claim 1 , wherein the force sensor comprises:
a sensor resistor having a resistance that is configured to vary according to a sensor force received at the sensor resistor;
a filter resistor having a constant resistance value and connected in series to the sensor resistor; and
a force sensing part connected to a node that is connected between the sensor resistor and the filter resistor,
wherein the sensor resistor and the filter resistor are configured for dividing a reference voltage to provide a division voltage at the node, and wherein the force sensing part is configured to determine the sensor force using a value of the a division voltage.

5. The display device of claim 4 , wherein the force sensor senses an arrival time of a surface acoustic wave generated by the touch and the touch distance is calculated by:
D=v×Δt
wherein D indicates the touch distance, v indicates a transfer speed of the surface acoustic wave, Δt indicates the arrival taken for the surface acoustic wave to reach the force sensor.

6. The display device of claim 1 , wherein the first angle sensor overlaps the force sensor in a direction perpendicular to a surface of the touch substrate.

7. The display device of claim 1 , further comprising:
a frame disposed on the touch substrate, having an opening, and including an inner wall for reflecting infrared light provided by at least one of the first angle sensor and the second angle sensor.

8. The display device of claim 7 , wherein the frame includes a cavity, and wherein the first angle sensor is disposed inside the cavity.

9. The display device of claim 7 , further comprising:
a reflection plate disposed at the inner wall for reflecting the infrared light.

10. The display device of claim 1 , further comprising:
a supporter disposed at the second corner of the touch substrate, wherein a height of the supporter is equal to a height of the force sensor.

11. The display device of claim 1 , wherein the computation part comprises:
a candidate coordinate calculator configured to calculate a first candidate coordinate related to the touch using two of the first touch angle, the second touch angle, and the distance, the candidate coordinate calculated being further configured to calculate a second candidate coordinate;
a coordinate calculator configured to select the touch coordinate from the first candidate coordinate and the second candidate coordinate using the remaining one of the first touch angle, the second touch angle, and the touch distance; and
a touch force calculator configured to calculate the touch force based on the touch distance and the sensor force.

12. The display device of claim 11 , wherein the candidate coordinate calculator calculates the candidate coordinate by:
xy =( D ·cos(θ), D ·sin(θ))

wherein xy indicates the candidate coordinate, D indicates the touch distance, and θ indicates the first touch angle.

13. The display device of claim 12 , wherein the coordinate calculator is configured to select the touch coordinate from the first candidate coordinate and the second candidate coordinate using the second touch angle.

14. The display device of claim 11 , wherein the candidate coordinate calculator calculates the candidate coordinate by:

xy
=

(

-

tan
⁡

(
Φ
)

·
W

tan
⁡

(
θ
)

-

tan
⁡

(
Φ
)

,

-

tan
⁡

(
θ
)

·

tan
⁡

(
Φ
)

·
W

tan
⁡

(
θ
)

-

tan
⁡

(
Φ
)

)

wherein xy indicates the candidate coordinate, θ indicates the first touch angle, Φ indicates the second touch angle, and W indicates a width of the touch substra

Assignees

• Samsung Display Co Ltd

Inventors

• Hong Won-Ki
• Nam Seungho
• Jang Hyeonyong

Classifications

• G06F3/0414 Primary

  using force sensing means to determine a position · CPC title

• G06F3/0433

  in which the acoustic waves are either generated by a movable member and propagated within a surface layer or propagated within a surface layer and captured by a movable member · CPC title

• G06F3/0428

  by sensing at the edges of the touch surface the interruption of optical paths, e.g. an illumination plane, parallel to the touch surface which may be virtual (sensing beam interruptions in a planar beam grid of an optical touch-screen G06F3/0421) · CPC title

• G06F3/0416

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F2203/04105

  Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position · CPC title