LCD Panel with Index-Matching Passivation Layers

• US 20100208158A1
• Filed: 02/13/2009
• Published: 08/19/2010
• Est. Priority Date: 02/13/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Chen, Cheng, Zhong, John Z., Chang, Shih Chang, Gu, Mingxia
• Granted Patent: US 8,558,978 B2
• Time in Patent Office: Days
• US Class Current: 349/56
• CPC Class Codes: G02F 1/133502 Antiglare, refractive index matching layers
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence

Abstract

A liquid crystal display (LCD) having one or more index-matching layers is provided. In one embodiment, an index-matching passivation layer is provided between two additional layers of the LCD. The index-matching passivation layer may include a refractive index greater than a first layer of the two additional layers and less than a second layer of the two additional layers. Various additional devices and methods are also provided.

Claims

1. A liquid crystal display (LCD) panel comprising a display stack including a plurality of layers, the plurality of layers comprising:

a gate insulation layer disposed over a substrate;

a first electrode layer disposed over the gate insulation layer;

an insulating layer disposed over the first electrode layer;

a second electrode layer disposed over the insulating layer;

a liquid crystal layer disposed over the second electrode layer; and

an index-matching layer interposed between at least two layers of the plurality of layers, wherein the index-matching layer includes a refractive index greater than that of a first layer of the at least two layers and less than that of a second layer of the at least two layers.

2. The LCD panel of claim 1, wherein the refractive index of the index-matching layer is approximately equal to the square root of the product of the refractive indices of the first and second layers.

3. The LCD panel of claim 1, wherein the at least two layers comprise the gate insulation layer and the first electrode layer.

4. The LCD panel of claim 1, wherein the at least two layers comprise the insulating layer and the liquid crystal layer.

5. The LCD panel of claim 1, wherein the gate insulation layer is disposed in contact with the substrate.

6. The LCD panel of claim 1, wherein the first and second electrode layers comprise a common electrode and a plurality of pixel electrodes, respectively.

7. An electronic device, comprising:

one or more input structures;

a storage structure encoding one or more executable routines;

a processor capable of receiving inputs from the one or more input structures and of executing the one or more executable routines when loaded in a memory; and

a liquid crystal display (LCD) capable of displaying an output of the processor, wherein the LCD includes;

a first passivation layer disposed in contact with a second passivation layer, wherein the first passivation layer includes a refractive index less than that of the second passivation layer;

a plurality of electrodes formed on a common surface of the first passivation layer; and

a liquid crystal layer disposed over the plurality of electrodes, wherein the electrodes of the plurality of electrodes are spaced apart along the common surface such that portions of the liquid crystal layer are disposed between the electrodes and the first passivation layer.

8. The electronic device of claim 7, wherein the refractive index of the first passivation layer is greater than a refractive index of the liquid crystal layer.

9. The electronic device of claim 8, wherein the refractive index of the first passivation layer is greater than a refractive index of the plurality of electrodes.

10. The electronic device of claim 7, wherein the first passivation layer includes a plurality of regions having different refractive indices.

11. The electronic device of claim 10, wherein the plurality of regions includes a first region in contact with an electrode of the plurality of electrodes and a second region in contact with the liquid crystal layer.

12. The electronic device of claim 11, wherein the first region of the first passivation layer has a refractive index between those of the second passivation layer and the electrode, while the second region of the first passivation level has a refractive index between those of the second passivation layer and the liquid crystal layer.

13. A display panel comprising:

a plurality of transparent layers disposed between two transparent substrates, wherein the plurality of transparent layers includes;

a passivation layer; and

first and second additional layers disposed opposite one another about the passivation layer such that the first and second additional layers interface with opposing surfaces of the passivation layer;

wherein the passivation layer includes a refractive index between those of the first and second additional layers such that, when light is transmitted through the display panel, the aggregate amount of light reflected at the respective interfaces between the first and second additional layers and the passivation layer is less than the amount of light that would be reflected by an interface between the first and second additional layers.

14. The display panel of claim 13, wherein the first and second additional layers include respective refractive indices of approximately 1.5 and 1.8.

15. The display panel of claim 14, wherein the refractive index of the passivation layer is approximately 1.64.

16. The display panel of claim 13, wherein the first and second additional layers include respective refractive indices of approximately 1.5 and 2.0.

17. The display panel of claim 16, wherein the refractive index of the passivation layer is approximately 1.74.

18. The display panel of claim 13, wherein the display panel comprises a liquid crystal display (LCD) panel.

19. The display panel of claim 18, wherein the LCD panel comprises a fringe field switching LCD panel.

20. A liquid crystal display (LCD) panel comprising:

a substrate;

a control layer disposed over the substrate, wherein the control layer includes a plurality of layers and is configured to generate and vary electric fields, the plurality of layers including a first passivation layer, a second passivation layer disposed over and in contact with the first passivation layer, and a third passivation layer disposed over and in contact with the second passivation layer, wherein the second passivation layer has a refractive index different than that of the first and third passivation layers; and

a liquid crystal layer including a plurality of liquid crystals responsive to the electric fields generated by the control layer.

21. The LCD panel of claim 20, wherein the first and third passivation layers have different refractive indices.

22. The LCD panel of claim 20, wherein at least one of the first, second, and third passivation layers comprises an organic passivation layer.

23. The LCD panel of claim 22, wherein the first, second, and third passivation layers respectively include an inorganic passivation layer, an index-matching layer having a refractive index between those of the first and third passivation layers, and an organic passivation layer.

24. The LCD panel of claim 20, wherein the first passivation layer has a refractive index between those of the second passivation layer and a first additional layer in contact with the first passivation layer opposite the second passivation layer.

25. The LCD panel of claim 24, wherein the third passivation layer has a refractive index between those of the second passivation layer and a second additional layer in contact with the third passivation layer opposite the second passivation layer.

26. The LCD panel of claim 25, wherein the second additional layer includes the liquid crystal layer.

27. A method of manufacturing a liquid crystal display (LCD) panel, the method comprising:

forming a plurality of layers on a substrate, wherein forming the plurality of layers comprises;

forming an index-matching passivation layer on a first additional layer; and

forming a second additional layer on the index-matching passivation layer;

wherein the index-matching passivation layer has a refractive index greater than one of the first or second additional layers and less than the other of the first or second additional layers.

28. The method of claim 27, comprising:

coupling the substrate to an additional substrate; and

providing a liquid crystal layer between the substrate and the additional substrate.