TOUCH PANEL, ELECTROOPTICAL DEVICE, AND ELECTRONIC APPARATUS

Abstract

A touch panel includes a first touch panel substrate; a second touch panel substrate disposed opposite the first touch panel substrate; at least one surface acoustic wave generator that generates a surface acoustic wave propagating across a surface of the second touch panel substrate facing the first touch panel substrate in a predetermined direction; at least one surface acoustic wave sensor that senses the surface acoustic wave generated by the surface acoustic wave generator; a position detector that detects a position where the first touch panel substrate is pressed according to the waveform of the surface acoustic wave sensed by the surface acoustic wave sensor; and spacers disposed between the first and second touch panel substrates along a path where the surface acoustic wave propagates from the surface acoustic wave generator to the surface acoustic wave sensor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.

FIG. 1 is a sectional view of a liquid crystal device according to a first embodiment of the invention.

FIG. 2 is a plan view of the liquid crystal device according to this embodiment.

FIG. 3 is a schematic diagram of a touch panel touched by a user.

FIG. 4 is a graph showing the waveform of a surface acoustic wave detected by a receiving transducer.

FIG. 5 is a sectional view of a liquid crystal device according to a second embodiment of the invention.

FIG. 6 is a sectional view of a liquid crystal device according to a third embodiment of the invention.

FIG. 7 is a sectional view of a liquid crystal device according to a fourth embodiment of the invention.

FIG. 8 is a sectional view of a liquid crystal device according to a fifth embodiment of the invention.

FIG. 9 is a plan view of a liquid crystal device according to a sixth embodiment of the invention.

FIG. 10 is a schematic diagram of an electronic apparatus according to a seventh embodiment of the invention.

Claims

1. A touch panel comprising: a first touch panel substrate;a second touch panel substrate disposed opposite the first touch panel substrate;at least one surface acoustic wave generator that generates a surface acoustic wave propagating across a surface of the second touch panel substrate facing the first touch panel substrate in a predetermined direction;at least one surface acoustic wave sensor that senses the surface acoustic wave generated by the surface acoustic wave generator;a position detector that detects a position where the first touch panel substrate is pressed according to the waveform of the surface acoustic wave sensed by the surface acoustic wave sensor; andspacers disposed between the first and second touch panel substrates along a path where the surface acoustic wave propagates from the surface acoustic wave generator to the surface acoustic wave sensor.

2. A touch panel comprising: a first touch panel substrate;a second touch panel substrate disposed opposite the first touch panel substrate;at least one surface acoustic wave generator that generates a surface acoustic wave propagating across a surface of the second touch panel substrate facing the first touch panel substrate in a predetermined direction;at least one surface acoustic wave sensor that senses the surface acoustic wave generated by the surface acoustic wave generator;a position detector that detects a position where the first touch panel substrate is pressed according to the waveform of the surface acoustic wave sensed by the surface acoustic wave sensor; andspacers disposed between the first and second touch panel substrates in a region where the surface acoustic wave generated by the surface acoustic wave generator does not propagate on the surface of the second touch panel substrate facing the first touch panel substrate.

3. The touch panel according to claim 1, wherein an adhesive is applied to portions of the spacers in contact with the first touch panel substrate and/or portions of the spacers in contact with the second touch panel substrate.

4. The touch panel according to claim 1, wherein portions of the spacers in contact with the first and second touch panel substrates are narrower than the width of the minimum detection resolution of the position detector.

5. An electrooptical device comprising: the touch panel according to claim 1, anda display panel disposed opposite the touch panel and having a display surface where an image is displayed.

6. The electrooptical device according to claim 5, wherein the first touch panel substrate is formed of a resin film.

7. The electrooptical device according to claim 5, wherein the first touch panel substrate is a polarizer.

8. The electrooptical device according to claim 7, further comprising a resin film disposed on a surface of the first touch panel substrate facing the second touch panel substrate.

9. An electrooptical device comprising: a first touch panel substrate;a second touch panel substrate disposed opposite the first touch panel substrate;a display panel disposed opposite a surface of the second touch panel substrate facing away from the first touch panel substrate with a predetermined gap defined therebetween;at least one surface acoustic wave generator that generates a surface acoustic wave propagating across the surface of the second touch panel substrate facing away from the first touch panel substrate in a predetermined direction;at least one surface acoustic wave sensor that senses the surface acoustic wave generated by the surface acoustic wave generator;a position detector that detects a position where the first touch panel substrate is pressed according to the waveform of the surface acoustic wave sensed by the surface acoustic wave sensor; andspacers disposed between the second touch panel substrate and the display panel along a path where the surface acoustic wave propagates from the surface acoustic wave generator to the surface acoustic wave sensor.

10. The electrooptical device according to claim 9, wherein an adhesive is applied to portions of the spacers in contact with the second touch panel substrate and/or portions of the spacers in contact with the display panel.

11. The electrooptical device according to claim 9, wherein portions of the spacers in contact with the second touch panel substrate and the display panel are narrower than the width of the minimum detection resolution of the position detector.

12. The electrooptical device according to claim 9, wherein the first touch panel substrate is a polarizer.

13. The electrooptical device according to claim 9, further comprising a resin film disposed on a surface of the display panel facing the second touch panel substrate.

14. The electrooptical device according to claim 8, wherein the resin film has a birefringence phase difference of substantially zero.

15. The electrooptical device according to claim 8, wherein the direction of the polarization axis of the polarizer substantially agrees with the direction of the slow or fast axis of the resin film.

16. The electrooptical device according to claim 8, wherein the birefringence phase difference of the resin film and the directions of the slow and fast axes thereof are selected so as to compensate for the birefringence phase difference of the display panel.

17. An electronic apparatus comprising the electrooptical device according to claim 5.