Display panel and display device

Patent metadata

Field	Value
Publication number	US-9304369-B2
Application number	US-201314401059-A
Country	US
Kind code	B2
Filing date	May 15, 2013
Priority date	May 16, 2012
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

A display panel includes: a substrate constituted by an active matrix substrate; a substrate opposite the substrate; and a light modulation layer interposed between the substrates. The change in the magnitude or the frequency of the voltage applied between a pixel electrode and a common electrode rotates a shape-anisometric member in the light modulation layer, and the pixel electrode extends over a scan signal line over an insulating layer.

First claim

What is claimed is:

1. A display panel, comprising:
a first substrate and a second substrate facing each other; and
a light modulation layer sandwiched between the first substrate and the second substrate, the light modulation layer including a medium and a plurality of anisometric members such that an area of the anisometric members projected through the anisometric members in a direction normal to the substrates changes by rotation,
wherein the first substrate is an active matrix substrate including a plurality of scan signal lines, a plurality of data signal lines that intersect with the scan signal lines, a plurality of switching elements disposed at respective intersections of the scan signal lines and the data signal lines, and a plurality of pixel electrodes connected to the respective switching elements,
wherein the second substrate is an opposite substrate having an opposite electrode that faces the pixel electrodes,
wherein the projected area of the anisometric members with respect to the first substrate and the second substrate is changed by rotating the anisometric members through changing an amount or a frequency of a voltage applied between the plurality of pixel electrodes and the opposite electrode, and
wherein the pixel electrodes extend over the scan signal lines with an insulating layer therebetween.

2. The display panel according to claim 1 , wherein the pixel electrodes extend over the scan signal lines such that the scan signal lines are respectively disposed across central portions of the respective pixel electrodes.

3. The display panel according to claim 1 , wherein the pixel electrodes respectively overlap the scan signal lines and the data signal lines across the insulating layer.

4. A display device, comprising the display panel according to claim 1 .

5. The display panel according to claim 1 , wherein a thickness of the light modulation layer is 10 times to 50 times larger than a distance between adjacent pixel electrodes.

6. The display panel according to claim 5 , wherein a permittivity of the anisometric members is less than a permittivity of the medium.

7. The display panel according to claim 1 , wherein a voltage applied between the pixel electrodes and the opposite electrode is switched between a direct current with 0Hz frequency or a low frequency less than or equal to a prescribed first threshold and a high frequency greater than or equal to a prescribed second threshold.

8. The display panel according to claim 7 ,
wherein the anisometric members are oriented such that long axes thereof are parallel to the first substrate and the second substrate when the voltage applied between the pixel electrodes and the opposite electrode is the direct current or has the low frequency less than or equal to the first threshold, and
wherein the anisometric members are oriented such that the long axes thereof are perpendicular to the first substrate and the second substrate when the voltage applied between the pixel electrodes and the opposite electrode has the high frequency greater than or equal to the second threshold.

9. The display panel according to claim 1 , wherein the anisometric members have a charge.

10. The display panel according to claim 9 , wherein the charge of the anisometric members and a charge of the opposite electrode have different polarities from each other when a direct current voltage is applied to the pixel electrodes and the opposite electrode.

11. The display panel according to claim 1 , wherein the anisometric members have reflective surfaces and perform reflective display by reflecting light that is incident on the reflective surfaces.

12. The display panel according to claim 11 ,
wherein the insulating layer includes a light-absorption layer, and
wherein the display panel performs black display by the light-absorption layer absorbing external light that passes through the light modulation layer when the anisometric members are rotated such that the long axes thereof are perpendicular to the substrates.

13. The display panel according to claim 1 , further comprising:
insulating members each having a protruding shape that protrudes into the light modulation layer in an area overlapping one of the scan signal lines when viewed from a direction normal to the substrate, said area being between pixel electrodes adjacent to each other in an extension direction of said scan signal lines.

14. The display panel according to claim 13 , wherein the insulating member having the protruding shape is a spacer that defines a thickness of the light modulation layer.

15. The display panel according to claim 13 ,
wherein the insulating member having the protruding shape is a rib formed on one of the first substrate or the second substrate, and
wherein a gap between the rib and another one of the first substrate or the second substrate facing the rib is smaller than a long axis of the anisometric member.

Assignees

• Sharp Kk

Inventors

• Nakamura Kohzoh
• Satoh Eiji
• Watanabe Hisashi
• Nakahara Takahiro

Classifications

• G02F1/167 Primary

  by electrophoresis · CPC title

• G02F1/133512

  Light shielding layers, e.g. black matrix (G02F1/136209 takes precedence) · CPC title

• G02F1/1368

  in which the switching element is a three-electrode device {(G02F1/136277 takes precedence)} · CPC title

• G02F1/133345

  Insulating layers (G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence) · CPC title

• G02F1/136286

  Wiring, e.g. gate line, drain line · CPC title