Pressure sensor and display device including the same

Patent metadata

Field	Value
Publication number	US-11609609-B2
Application number	US-202016851740-A
Country	US
Kind code	B2
Filing date	Apr 17, 2020
Priority date	Oct 8, 2019
Publication date	Mar 21, 2023
Grant date	Mar 21, 2023

Abstract

A pressure sensor, includes: a first substrate; a pressure sensing layer on one surface of the first substrate; and a driving electrode and a sensing electrode on the pressure sensing layer and spaced apart from each other, wherein the driving electrode and the sensing electrode are on a same layer, and each of the driving electrode and the sensing electrode is directly on the pressure sensing layer.

First claim

What is claimed is:

1. A pressure sensor, comprising:
a first substrate;
a pressure sensing layer on one surface of the first substrate; and
a driving electrode and a sensing electrode on the pressure sensing layer and spaced apart from each other,
wherein the driving electrode and the sensing electrode are on a same layer, and
each of the driving electrode and the sensing electrode is directly on the pressure sensing layer, and
wherein the pressure sensing layer includes a polymer resin having metal particles,
wherein a contact area between the pressure sensing layer and the driving electrode and a contact area between the pressure sensing layer and the sensing electrode are increased when a pressure is applied rather than when the pressure is not applied,
wherein the pressure sensing layer includes a first portion on one surface of the first substrate, and a plurality of second portions protruding from the first portion toward the sensing electrode and the driving electrode,
wherein the driving electrode includes a first driving electrode portion, and a second driving electrode protruding from the first driving electrode portion to the pressure sensing layer, and
wherein the second driving electrode overlaps one of the plurality of second portions in a thickness direction of the first substrate, and the second driving electrode does not overlap a dap between adjacent second portions among the plurality of second portions in the thickness direction of the first substrate.

2. The pressure sensor of claim 1 , wherein the plurality of second portions are in direct contact with the driving electrode and the sensing electrode.

3. The pressure sensor of claim 2 ,
wherein the first portion is spaced apart from the driving electrode and the sensing electrode with a space therebetween.

4. The pressure sensor of claim 3 ,
wherein a first contact area between a second portion from among the second portions and the driving electrode and between the second portion and the sensing electrode before pressure is applied to the pressure sensor is smaller than a second contact area between the second portion and the driving electrode and between the second portion and the sensing electrode after pressure is applied to the pressure sensor.

5. The pressure sensor of claim 2 ,
wherein a cross-section of a second portion from among the second portions has a semi-circular shape, a semi-elliptic shape, a triangular shape, a trapezoidal shape, or a rectangular shape.

6. The pressure sensor of claim 1 ,
the sensing electrode includes a first sensing electrode portion, and a second sensing electrode protruding from the first sensing electrode portion to the pressure sensing layer.

7. The pressure sensor of claim 6 ,
wherein a second driving electrode portion is in direct contact with the pressure sensing layer, and a second sensing electrode portion is in direct contact with the pressure sensing layer.

8. The pressure sensor of claim 1 ,
wherein each of the driving electrode and the sensing electrode extends along a first direction, and a plurality of driving electrodes comprising the driving electrode and a plurality of sensing electrodes comprising rhe sensing electrode are provided; and
the plurality of the driving electrodes and the plurality of the sensing electrodes are alternately arranged along a second direction crossing the first direction in a plan view, and each of the driving electrode and the sensing electrode includes a plurality of patterns.

9. A pressure sensor, comprising:
a first substrate;
a second substrate facing the first substrate;
a pressure sensing layer on one surface of the first substrate facing the second substrate; and
a driving electrode and a sensing electrode on one surface of the second substrate facing the first substrate and spaced apart from each other,
wherein the driving electrode and the sensing electrode are on a same layer, and
the pressure sensing layer includes an uneven structure on a surface facing the driving electrode and the sensing electrode,
wherein the pressure sensing layer includes a first portion on one surface of the first substrate, and a plurality of second portions indented from the first portion toward the first substrate, and
the plurality of second portions overlap the driving electrode and the sensing electrode in a thickness direction, and do not overlap a space between the driving electrode and the sensing electrode.

10. A display device, comprising:
a display panel; and
a pressure sensor under the display panel,
wherein the pressure sensor includes:
a first substrate;
a pressure sensing layer on one surface of the first substrate; and
a driving electrode and a sensing electrode on the pressure sensing layer and spaced apart from each other,
wherein the driving electrode and the sensing electrode are on a same layer, and
each of the driving electrode and the sensing electrode is directly on the pressure sensing layer, and
wherein the pressure sensing layer includes a polymer resin having metal particles,
wherein a contact area between the pressure sensing layer and the driving electrode and a contact area between the pressure sensing layer and the sensing electrode are increased when a pressure is applied rather than when the pressure is not applied,
wherein the pressure sensing layer includes a first portion on one surface of the first substrate, and a plurality of second portions protruding from the first portion toward the sensing electrode and the driving electrode,
wherein each of the driving electrode and the sensing electrode includes an indentation pattern indented in a direction opposite to the pressure sensing layer, and
wherein the indentation pattern overlaps a gap between adjacent second portions among the plurality of second portions.

11. The display device of claim 10 ,
wherein each of the driving electrode and the sensing electrode extends along a first direction, and a plurality of driving electrodes comprising the driving electrode and a plurality of sensing electrodes comprising the sensing electrode are provided; and
the plurality of the driving electrodes and the plurality of the sensing electrodes are alternately arranged along a second direction crossing the first direction in a plan view, and each of the driving electrode and the sensing electrode includes a plurality of patterns.

Assignees

• Samsung Display Co Ltd

Inventors

• Park So Hee
• Hong Won Ki
• Seomoon Hee
• Lee Hyeon Jun

Classifications

• G01D5/241

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• G06F3/04144

  using an array of force sensing means (position sensing using the local deformation of sensor cells G06F3/0447) · CPC title

• G06F2203/04102

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• G06F2203/04105

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

• G06F3/0412

  Digitisers structurally integrated in a display · CPC title