Touch Panel and Touch Type Input Device

• US 20160034073A1
• Filed: 08/10/2015
• Published: 02/04/2016
• Est. Priority Date: 06/11/2009
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Andoh, Masamichi
• Granted Patent: US 9,804,725 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/04144 using an array of force sensing means position sensing using the local deformation of sensor cells G06F3/0447
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G06F 3/046 by electromagnetic means

Abstract

A touch panel that includes a film having piezoelectric properties, the film having a first principal plane and a second principal plane. A divided electrode is on the first principal plane, and a uniform ground electrode is on the second principal plane and arranged opposite to the divided electrode on the first principal plane.

Claims

1. A touch panel comprising:

a film having piezoelectric properties, the film having a first principal plane and a second principal plane;

a divided electrode on the first principal plane; and

a uniform ground electrode on the second principal plane and arranged opposite to the divided electrode on the first principal plane.

2. The touch panel according to claim 1, wherein the divided electrode and the uniform ground electrode are configured to detect a pressure of the input toward the film having piezoelectric properties based on a voltage generated within the film having piezoelectric properties by deformation of the film having piezoelectric properties.

3. The touch panel according to claim 1, wherein the film having piezoelectric properties is a piezoelectric polymer.

4. The touch panel according to claim 2, wherein the film having piezoelectric properties is a molecule oriented polylactic acid film.

5. The touch panel according to claim 4, wherein the polylactic acid film is configured to generate a voltage based on deformation of the polylactic acid film, and each of the sections of the divided electrode output respective voltages resulting from the deformation of the polylactic acid film so that position information of a pressing location of the touch panel is determined based on differences between the respective voltages output from each of the sections of the divided electrode.

6. The touch panel according to claim 1, wherein the divided electrode is electrically divided by a plurality of electrode division lines including electrode non-forming portions.

7. The touch panel according to claim 6, wherein the electrode division lines are straight lines having a predetermined width.

8. The touch panel according to claim 6, wherein the electrode division lines cross at a point in substantially a center of the polylactic acid film at predetermined angles.

9. The touch panel according to claim 8, wherein the predetermined angles formed by the electrode division lines are equal to each other.

10. The touch panel according to claim 6, wherein the polylactic acid film is molecule oriented by uniaxially stretching.

11. The touch panel according to claim 10,

wherein the plurality of electrode division lines include at least a first electrode division line and a second electrode division line,

wherein when a first angle formed by the first electrode division line and a stretching direction of the polylactic acid film is θ

₁ and a second angle formed by the second electrode division line and the stretching direction of the polylactic acid film is θ

₂, and θ

₁ and θ

₂ satisfy;

−

12°

≦

θ

₁≦

12°

,−

102°

≦

θ

₂≦

−

78°

.

12. The touch panel according to claim 11,

wherein the first electrode division line is in a direction which substantially coincides with the stretching direction of the polylactic acid film,

wherein the second electrode division line is in a direction substantially orthogonal to the first electrode division line.

13. The touch panel according to claim 1, wherein at least one of the divided electrode on the first principal plane and the uniform ground electrode on the second principal plane is a transparent electrode having ZnO as a main component.

14. The touch panel according to claim 4, wherein the molecule oriented polylactic acid film includes two or more stacked polylactic acid films.

15. The touch panel according to claim 1, wherein the film having piezoelectric properties is a polylactic acid film that has been molecularly oriented and thermally treated so as to have a d₁₄ piezoelectric property.

16. The touch panel according to claim 15, wherein the divided electrode and the uniform ground electrode are configured to detect a relative position of an input on the polylactic acid film and detect a pressure of the input toward the polylactic acid film based on a voltage generated within the polylactic acid film by deformation of the polylactic acid film.

17. A touch type input device comprising:

the touch panel according to claim 16; and

a processor connected to the sections of the divided electrode, the processor configured to output the position information and/or pressed information based on the respective voltages in the sections of the divided electrode.

18. The touch type input device according to claim 17, wherein the processor includes at least:

a detection unit which detects the respective voltages in the sections of the divided electrode;

a storage unit which stores a plurality of stored voltage patterns determined previously from the respective voltages generated in the sections of the divided electrode and a plurality of pieces of position information corresponding thereto; and

a computation unit which creates a detected voltage pattern from the respective voltages detected by the detection unit, compares the detected voltage pattern with the stored voltage patterns, checks the corresponding voltage patterns with a predetermined threshold value to output the position information, and computes the pressed information from a predetermined voltage similarity ratio of the stored voltage pattern and the detected voltage pattern which have been checked.

19. A touch type input device comprising:

the touch panel according to claim 5; and

a processor connected to the sections of the divided electrode, the processor configured to output the position information and/or pressed information based on the respective voltages in the sections of the divided electrode.

20. The touch type input device according to claim 19, wherein the processor includes at least:

a detection unit which detects the respective voltages in the sections of the divided electrode;

a storage unit which stores a plurality of stored voltage patterns determined previously from the respective voltages generated in the sections of the divided electrode and a plurality of pieces of position information corresponding thereto; and

a computation unit which creates a detected voltage pattern from the respective voltages detected by the detection unit, compares the detected voltage pattern with the stored voltage patterns, checks the corresponding voltage patterns with a predetermined threshold value to output the position information, and computes the pressed information from a predetermined voltage similarity ratio of the stored voltage pattern and the detected voltage pattern which have been checked.