Touch Panel and Touch Type Input Device

• US 20130328817A1
• Filed: 08/16/2013
• Published: 12/12/2013
• 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 9,128,553 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• 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 sensing apparatus that includes a polylactic acid film having a first surface and an opposing second surface. The polylactic acid film is molecularly oriented and thermally treated so as to have a shear piezoelectric property. An electrode arrangement is provided adjacent at least one of the first and second surfaces of the polylactic acid film, and is 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.

Claims

1. A sensing apparatus comprising:

a polylactic acid film having a first surface and an opposing second surface, the polylactic acid film being molecularly oriented and thermally treated so as to have a shear piezoelectric property; and

an electrode arrangement adjacent at least one of the first and second surfaces of the polylactic acid film, the electrode arrangement being 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.

2. The sensing device according to claim 1, wherein the polylactic acid film is an L type polylactic acid film.

3. The sensing device according to claim 1, wherein the polylactic acid film is a D type polylactic acid film.

4. The sensing device according to claim 1, wherein the electrode arrangement comprises:

a divided electrode on the first surface of the polylactic acid film, the divided electrode being electrically divided into at least four sections; and

an electrode on the opposing second surface.

5. The sensing device according to claim 4, wherein the electrode on the opposing second surface of the polylactic acid film is a divided electrode having respective sections opposite to the sections of the divided electrode on the first surface of the polylactic acid film.

6. The sensing device according to claim 4, wherein the electrode on the opposing second surface of the polylactic acid film is a uniform ground electrode arranged opposite to the divided electrode on the first surface of the polylactic acid film.

7. The sensing device according to claim 4, wherein the divided electrode is electrically divided by a plurality of electrode division lines including electrode non-forming portions.

8. The sensing device according to claim 7, wherein the electrode division lines are straight lines having a predetermined width.

9. The sensing device according to claim 7, wherein the electrode division lines cross at a point in substantially a center of the polylactic acid film at predetermined angles.

10. The sensing device according to claim 9, wherein the predetermined angles formed by the electrode division lines are equal to each other.

11. The sensing device according to claim 7,

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 sensing device 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 sensing device according to claim 4, wherein at least one of the divided electrode on the first surface of the polylactic acid film and the electrode on the opposing second surface of the polylactic acid film is a transparent electrode having ZnO as a main component.

14. The sensing device according to claim 1, wherein the polylactic acid film includes two or more stacked polylactic acid films.

15. A touch type input device comprising:

the sensing device according to claim 1; and

a processor connected to the electrode arrangement, the processor configured to output at least one of position information and pressed information based on voltages detected from the electrode arrangement.

16. The touch type input device according to claim 15, wherein the processor includes at least:

a detection unit which detects voltages generated in portions of the electrode arrangement;

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

a computation unit which creates a detected voltage pattern from the 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.

17. A touch type input device comprising:

the sensing device according to claim 4; and

a processor connected to the sections of the divided electrode, the processor configured to output at least one of position information and pressed information based on voltages detected independently from 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 respective voltages generated 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.