Display module with pressure sensor

• US 9,921,700 B2
• Filed: 01/05/2016
• Issued: 03/20/2018
• Est. Priority Date: 07/29/2015
• Status: Active Grant

• Current Assignee: FocalTech Systems Co.,Ltd
• Original Assignee: FocalTech Systems Co.,Ltd
• Inventors: Kung, Chen-Pang
• Primary Examiner(s): Bibbins, Latanya
• Application Number:
  US14/987,996
• Publication Number:
  US 20170031476A1
• Time in Patent Office: 805 Days
• 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 3/0447 Position sensing using the local deformation of sensor cells

Abstract

A display module includes a front panel, a backlight panel, a pressure sensor and a panel frame. The front panel includes an array of display pixels. The backlight panel is disposed under the front panel. The pressure sensor is disposed under the backlight panel, and includes a top electrode layer, an interlayer and a bottom electrode layer. The bottom electrode layer includes plural sub-electrodes. If a first distance between a first sub-electrode and a geometric center of the bottom electrode layer is shorter than a second distance between a second sub-electrode and the geometric center, an area of the second sub-electrode is larger than an area of the first sub-electrode. The panel frame is disposed under the pressure sensor. When an applied pressure is received by the front panel, a magnitude of the applied pressure is sensed by the pressure sensor.

Claims

1. A display module, comprising:

a front panel comprising an array of display pixels;

a backlight panel disposed under the front panel;

a pressure sensor disposed under the backlight panel and attached on the backlight panel, and the pressure sensor comprising a top electrode layer, an interlayer and a bottom electrode layer, wherein the bottom electrode layer comprises plural sub-electrodes, wherein areas of the sub-electrodes are determined according to distances between the sub-electrodes to a geometric center of the bottom electrode layer; and

the sub-electrodes comprise a first sub-electrode, a second sub-electrode and a third sub-electrode, wherein if a first area of the first sub-electrode is smaller than a second area of the second sub-electrode and the second area of the second sub-electrode is smaller than a third area of the third sub-electrode, a first distance between the first sub-electrode and the geometric center is shorter than a second distance between the second sub-electrode and the geometric center, and the second distance between the second sub-electrode and the geometric center is shorter than a third distance between the third sub-electrode and the geometric center; and

a panel frame disposed under the pressure sensor,

wherein when an applied pressure is received by the front panel, a magnitude of the applied pressure is sensed by the pressure sensor.

2. The display module as claimed in claim 1, wherein the pressure sensor further comprises a first substrate and a second substrate, and the interlayer is arranged between the first substrate and the second substrate, wherein the first substrate comprises the top electrode layer, the second substrate comprises the bottom electrode layer, and the interlayer is a dielectric interlayer.

3. The display module as claimed in claim 1, wherein the panel frame comprises an insulation layer and a metallic frame.

4. The display module as claimed in claim 3, wherein the top electrode layer and the metallic frame are connected to a ground voltage.

5. The display module as claimed in claim 3, wherein the insulation layer is made of foam.

6. A display module, comprising:

an illumination module comprising a top electrode layer;

a pressure sensor attached on the backlight panel, and the pressure sensor comprising the top electrode layer, an interlayer and a bottom electrode layer, wherein the bottom electrode layer comprises plural sub-electrodes, wherein areas of the sub-electrodes are determined according to distances between the sub-electrodes to a geometric center of the bottom electrode layer; and

the sub-electrodes comprise a first sub-electrode, a second sub-electrode and a third sub-electrode, wherein if a first area of the first sub-electrode is smaller than a second area of the second sub-electrode and the second area of the second sub-electrode is smaller than a third area of the third sub-electrode, a first distance between the first sub-electrode and the geometric center is shorter than a second distance between the second sub-electrode and the geometric center, and the second distance between the second sub-electrode and the geometric center is shorter than a third distance between the third sub-electrode and the geometric center; and

a panel frame disposed under the pressure sensor,

wherein when an applied pressure is received by the front panel, a magnitude of the applied pressure is sensed by the pressure sensor.

7. The display module as claimed in claim 6, wherein the illumination module comprises:

a front panel comprising an array of display pixels; and

a backlight panel disposed under the front panel,

wherein the backlight panel comprises a reflective substrate and a light guide layer, and the reflective substrate is used as the top electrode layer of the pressure sensor.

8. The display module as claimed in claim 6, wherein the illumination module comprises:

a front panel comprising an array of display pixels, wherein the front panel further comprises a transparent electrode layer; and

a backlight panel disposed under the front panel,

wherein the transparent electrode layer is used as the top electrode layer of the pressure sensor.

9. The display module as claimed in claim 6, wherein the panel frame comprises an insulation layer and a metallic frame.

10. The display module as claimed in claim 9, wherein the top electrode layer and the metallic frame are connected to a ground voltage.

11. The display module as claimed in claim 9, wherein the insulation layer is made of foam.