Display apparatus
A display apparatus includes a display panel configured to display an image and a plurality of vibration generating devices configured to vibrate the display panel. Each of the plurality of vibration generating devices includes a plurality of first portions having a piezoelectric characteristic and a plurality of second portions disposed near the plurality of first portions to have an expansion coefficient, and the plurality of vibration generating devices have different expansion coefficients.
1. A display apparatus, comprising:
a display panel configured to display an image; and
a plurality of vibration generating devices configured to vibrate the display panel,
wherein each of the plurality of vibration generating devices comprises:
a plurality of first portions having a piezoelectric characteristic; and
a plurality of second portions disposed near the plurality of first portions to have a negative or zero expansion coefficient,
wherein the plurality of vibration generating devices comprise a first vibration generating device, a second vibration generating device, and a third vibration generating device, and
wherein an expansion coefficient of the first vibration generating device is less than an expansion coefficient of the second vibration generating device, and an expansion coefficient of the second vibration generating device is less than an expansion coefficient of the third vibration generating device.
2. The display apparatus of claim 1 , wherein the plurality of second portions are disposed between the plurality of first portions.
3. The display apparatus of claim 1 , wherein the plurality of first portions are disposed on the same plane as the plurality of second portions.
4. The display apparatus of claim 1 , wherein the plurality of second portions are disposed on upper surfaces or lower surfaces of the plurality of first portions.
5. The display apparatus of claim 1 , wherein the first vibration generating device is implemented as one or more of a receiver and a tweeter, the second vibration generating device is implemented as a speaker, and the third vibration generating device is implemented as a haptic device.
6. The display apparatus of claim 1 , wherein
the plurality of vibration generating devices comprise a first vibration generating device, a second vibration generating device, and a third vibration generating device, and
a width of each of the plurality of second portions of the first vibration generating device is less than a width of each of the plurality of second portions of the second vibration generating device, and a width of each of the plurality of second portions of the second vibration generating device is less than a width of each of the plurality of second portions of the third vibration generating device.
7. The display apparatus of claim 1 , wherein
the plurality of vibration generating devices comprise a first vibration generating device, a second vibration generating device, and a third vibration generating device, and
a width of each of the plurality of first portions of the first vibration generating device is less than a width of each of the plurality of first portions of the second vibration generating device, and a width of each of the plurality of first portions of the second vibration generating device is less than a width of each of the plurality of first portions of the third vibration generating device.
8. The display apparatus of claim 1 , wherein an expansion and contraction direction of each of the plurality of first portions is the same as an expansion and contraction direction of each of the plurality of second portions.
9. The display apparatus of claim 1 , further comprising:
an adhesive member between a rear surface of the display panel and the plurality of vibration generating devices;
a first electrode on an upper surface of the plurality of vibration generating devices under the adhesive member; and
a second electrode on a lower surface of the plurality of vibration generating devices.
10. The display apparatus of claim 9 , further comprising:
a first protection layer on an upper surface of the first electrode under the adhesive member; and
a second protection layer on a lower surface of the plurality of vibration generating devices.
11. The display apparatus of claim 1 , wherein each of the plurality of second portions is formed of an auxetic layer or a cork material.
12. The display apparatus of claim 1 , wherein the expansion coefficient of each of the plurality of second portions is within a range from −0.3 to 0.
13. The display apparatus of claim 1 , wherein the plurality of second portions have flexibility.
14. A display apparatus, comprising:
a display panel displaying an image; and
a plurality of vibration generating devices vibrating the display panel,
wherein:
each of the plurality of vibration generating devices comprises:
a plurality of piezoelectric portions having a piezoelectric characteristic; and
a plurality of expansion portions disposed near the plurality of piezoelectric portions,
the plurality of vibration generating devices are implemented to have different frequency characteristics,
the plurality of vibration generating devices comprise a first vibration generating device, a second vibration generating device, and a third vibration generating device, and
an expansion coefficient of each of the plurality of expansion portions of the first vibration generating device is less than an expansion coefficient of each of the plurality of expansion portions of the second vibration generating device, and the expansion coefficient of each of the plurality of expansion portions of the second vibration generating device is less than an expansion coefficient of each of the plurality of expansion portions of the third vibration generating device.
15. The display apparatus of claim 14 , wherein the plurality of piezoelectric portions are disposed on the same plane as the plurality of expansion portions.
16. The display apparatus of claim 14 , wherein the plurality of piezoelectric portions are disposed on upper surfaces or lower surfaces of the plurality of expansion portions.
17. The display apparatus of claim 14 , wherein the first vibration generating device has a frequency of a high-pitched sound band, the second vibration generating device has a frequency of a middle-pitched sound band, and the third vibration generating device has hag a frequency of a low-pitched sound band.
18. The display apparatus of claim 17 , wherein a frequency of the high-pitched sound band is 10 kHz to 20 kHz, a frequency of the middle-pitched sound band is 200 Hz to 10 kHz, and a frequency of the low-pitched sound band is 200 Hz or less.
19. The display apparatus of claim 17 , wherein the first vibration generating device is implemented as one or more of a receiver and a tweeter, the second vibration generating device is implemented as a speaker, and the third vibration generating device is implemented as a haptic device.
20. The display apparatus of claim 17 , wherein a width of each of the plurality of expansion portions of the first vibration generating device is less than a width of each of the plurality of expansion portions of the second vibration generating device, and a width of each of the plurality of expansion portions of the second vibration generating device is less than a width of each of the plurality of expansion portions of the third vibration generating device.
21. The display apparatus of claim 17 , wherein a width of each of the plurality of piezoelectric portions of the first vibration generating device is less than a width of each of the plurality of piezoelectric portions of the second vibration generating device, and a width of each of the plurality of piezoelectric portions of the second vibration generating device is less than a width of each of the plurality of piezoelectric portions of the third vibration generating device.
22. The display apparatus of claim 17 , wherein the first vibration generating device is disposed at an upper portion of the display panel, a second vibration generating device is disposed at a center portion of the display panel, and a third vibration generating device is disposed at a lower portion of the display panel.
23. The display apparatus of claim 17 , wherein the third vibration generating device is disposed at an upper portion of the display panel, the first vibration generating device is disposed at a center portion of the display panel, and the second vibration generating device is disposed at the lower portion of the display panel.
24. The display apparatus of claim 14 , further comprising:
a supporting member on a rear surface of the display panel; and
a partition between the display panel and the supporting member.
25. The display apparatus of claim 14 , further comprising a partition surrounding the plurality of vibration generating devices.
26. The display apparatus of claim 14 , further comprising:
a supporting member on a rear surface of the display panel;
a first partition between the display panel and the supporting member; and
a second partition surrounding the plurality of vibration generating devices.
27. The display apparatus of claim 26 , wherein the first partition is disposed along a region between a rear periphery of the display panel and a front periphery of the supporting member.
28. The display apparatus of claim 26 , wherein a size of the expansion partition is configured to adjust based on a characteristic of a sound band to be reproduced by the vibration of the display panel.
29. The display apparatus of claim 14 , wherein the plurality of expansion portions have flexibility.
30. The display apparatus of claim 14 , wherein each of the plurality of expansion portions has a negative or zero expansion coefficient.
31. The display apparatus of claim 30 , wherein each of the plurality of expansion portions is formed of an auxetic layer or a cork material.
32. The display apparatus of claim 30 , wherein the expansion coefficient of each of the plurality of expansion portions is within a range from −0.3 to 0.