DISPLAY DEVICE

• US 20180136756A1
• Filed: 01/11/2018
• Published: 05/17/2018
• Est. Priority Date: 08/07/2015
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: KANO, HIDEKAZU, Tsubaki, Nobuhito
• Granted Patent: US 11,112,893 B2
• Time in Patent Office: Days
• CPC Class Codes: G01L 1/16 using properties of piezoelectric devices
• CPC Class Codes: G02B 6/0045 by shaping at least a portion of the light guide
• CPC Class Codes: G02B 6/0051 Diffusing sheet or layer
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• 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 3/0412 Digitisers structurally integrated in a display
• 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: H10K 59/00 Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
• CPC Class Codes: H10K 59/126 Shielding, e.g. light-blocking means over the TFTs
• CPC Class Codes: H10K 59/40 OLEDs integrated with touch screens

Abstract

A display device includes a display portion, a light source, a reflecting member, and a piezoelectric element. The display portion displays an image. The light source outputs light to the display portion. The reflecting member is provided on one side of a principal surface of the display portion and reflects the light of the light source. The piezoelectric element is provided on one side of the principal surface of the reflecting member.

Claims

1. A display device comprising:

an operation panel;

a display located below the operation panel for displaying an image through the operation panel;

a light source located below the display for outputting light to the display;

a piezoelectric element located below the light source for detecting a pressing force applied to the operation panel, whereby the light source is located between the display and the piezoelectric element; and

a reflector located below the light source for reflecting light emitted by the light source toward the display.

2. The display device according to claim 1, wherein:

the piezoelectric element has first and second opposed principal surfaces, the first principal surface facing the light source, the second principal surface facing away from the light source;

a first electrode is disposed on the first principal surface of the piezoelectric element and is grounded; and

a second electrode is disposed on the second principal surface of the piezoelectric element.

3. The display device according to claim 2, wherein the first electrode is formed of a light reflecting material and serves as the reflector.

4. The display device according claim 1, wherein the first electrode is formed of a light reflecting material and serves, in addition to the reflector, to reflect light emitted by the light source towards the display.

5. The display device according to claim 2, wherein the second electrode has an area smaller than an area of the first electrode.

6. The display device according to claim 5, wherein the second electrode only covers part of second principal surface of the piezoelectric element and at least part of the area of the second principal surface of the piezoelectric element is covered dummy electrodes.

7. The display device according to claim 1, wherein the piezoelectric element contains polylactic acid.

8. The display device according to claim 1 further comprising a capacitive touch sensor located between the display and the operation panel.

9. A display device, comprising:

an operation panel;

a display located below the operation panel for displaying an image;

a light shielding member located below the display; and

a piezoelectric element located below the light shielding member such that the light shielding member is located between the display and the piezoelectric element.

10. The display device according to claim 9, wherein:

the piezoelectric element has first and second opposed principal surfaces, the first principal surface facing the light shielding member, the second principal surface facing away from the light shielding member;

a first electrode is disposed on the first principal surface of the piezoelectric element and is grounded; and

a second electrode is disposed on the second principal surface of the piezoelectric element.

11. The display device according to claim 10, wherein the second electrode has an area smaller than an area of the first electrode.

12. The display device according to claim 9, wherein the piezoelectric element contains polylactic acid.

13. A display device, comprising:

an operation panel;

a display located below the operation panel for displaying an image through the operation panel; and

a piezoelectric element located below the display and including first and second opposed principal surfaces, the first principal surface facing the display, the second principal surface facing away from the display;

a first electrode disposed on the first principal surface of the piezoelectric element, the first electrode being connected to ground; and

a second electrode disposed on the second principal surface of the piezoelectric element.