Flexible Display Panel With Bent Substrate

Patent metadata

Field	Value
Publication number	US-2016204366-A1
Application number	US-201614987129-A
Country	US
Kind code	A1
Filing date	Jan 4, 2016
Priority date	Jan 12, 2015
Publication date	Jul 14, 2016
Grant date	—

Abstract

A display may have an array of organic light-emitting diodes that form an active area on a flexible substrate. Metal traces may extend between the active area and an inactive area of the flexible substrate. Display driver circuitry such as a display driver integrated circuit may be coupled to the inactive area. The metal traces may extend across a bend region in the flexible substrate. The flexible substrate may be bent in the bend region. The flexible substrate may be made of a thin flexible material to reduce metal trace bending stress. A coating layer in the bend region may be provided with an enhanced elasticity to allow its thickness to be reduced. The flexible substrate may be bent on itself and secured within an electronic device without using a mandrel.

First claim

What is claimed is:

1 . A display, comprising:
a flexible substrate; an array of pixels that form an active area on the flexible substrate; metal traces that extend from the active area to an inactive area on the flexible substrate across a bend region on the flexible substrate, wherein the flexible substrate is folded over against itself at the bend region so that the active area overlaps the inactive area; first and second polymer layers interposed between the active area and the inactive area that is overlapped by the active area; and first, second, and third adhesive layers, wherein the first adhesive layer is interposed between the first polymer layer and the active area of the flexible substrate and attaches the first polymer layer to the active area of the flexible substrate, wherein the second adhesive layer is interposed between the second polymer layer and the inactive area of the flexible substrate and attaches the second polymer layer to the inactive area of the flexible substrate, and wherein the third adhesive layer is interposed between the first and second polymer layers and attaches the first and second polymer layers together.

2 . The display defined in claim 1 wherein the flexible substrate is a polyimide substrate with a thickness of less than 16 microns.

3 . The display defined in claim 1 wherein the flexible substrate is a polyimide substrate with an elasticity of less than 5 GPa.

4 . The display defined in claim 1 wherein the flexible substrate is coated with a coating layer in the bend region that has an elasticity of more than 0.7 GPa.

5 . The display defined in claim 4 wherein the flexible substrate is a polyimide substrate.

6 . The display defined in claim 5 wherein the flexible substrate has a thickness of less than 16 microns.

7 . The display defined in claim 1 wherein the first and second polymer layers have respective first and second edges at the bend region that are aligned with each other.

8 . The display defined in claim 1 wherein the first and second polymer layers have respective first and second edges and wherein the second adhesive layer has a protruding portion that extends from between the first and second polymer layers past the first and second edges.

9 . The display defined in claim 8 wherein the protruding portion contacts a surface of the flexible substrate.

10 . The display defined in claim 9 wherein the first and second edges are aligned with each other.

11 . The display defined in claim 1 wherein the first and second polymer layers have respective first and second edges at the bend region that are not aligned with each other.

12 . The display defined in claim 1 wherein the array of pixels comprises an array of organic light-emitting diode pixels.

13 . A display, comprising:
a flexible substrate having opposing first and second surfaces; an array of pixels that form an active area on the first surface of the flexible substrate, wherein the flexible substrate is folded at the bend region; and at least one layer of material that is attached between a first portion of the second surface of the flexible substrate and a second portion of the second surface of the flexible substrate.

14 . The display defined in claim 13 wherein the at least one layer of material comprises first and second polymer layers that are attached between the first portion of the second surface and the second portion of the second surface using adhesive.

15 . The display defined in claim 14 further comprising metal traces that extend from the active area to an inactive area on the flexible substrate across the bend region., wherein the inactive area is free of pixels.

16 . The display defined in claim 15 wherein the adhesive includes a layer of adhesive between the first and second polymer layers and wherein the layer of adhesive has a protruding portion that protrudes from between the first and second polymer layers and that contacts the flexible substrate.

17 . The display defined in claim 13 wherein the array of pixels comprises an array of organic light-emitting diode pixels.

18 . The display defined in claim 17 wherein the flexible substrate is coated with a coating layer in the bend region.

19 . An organic light-emitting diode display, comprising:
thin-film transistor circuitry that forms an array of pixels; a flexible substrate having a first surface on which the thin-film transistor circuitry is formed and having an opposing second surface, wherein the flexible substrate is bent back on itself so that a first portion of the second surface faces a second portion of the second surface; and at least one polymer layer and at least one layer of adhesive that attach the first portion to the second portion.

20 . The organic light-emitting diode defined in claim 19 wherein the flexible substrate is bent in a bent region, wherein the at least one polymer layer comprises first and second polymer layers, and wherein the at least one layer of adhesive includes adhesive between the first and second polymer layers that attaches the first polymer layer to the second polymer layer.

21 . Apparatus, comprising:
a flexible substrate; circuitry on the flexible substrate in a first area; metal traces that extend from the first area to an second area on the flexible substrate across a bend region on the flexible substrate, wherein the flexible substrate is folded over against itself at the bend region so that the first area overlaps the second area; first and second polymer layers interposed between the first area and the second area that is overlapped by the first area; and first, second, and third adhesive layers, wherein the first adhesive layer is interposed between the first polymer layer and the first area of the flexible substrate and attaches the first polymer layer to the first area of the flexible substrate, wherein the second adhesive layer is interposed between the second polymer layer and the second area of the flexible substrate and attaches the second polymer layer to the second area of the flexible substrate, and wherein the third adhesive layer is interposed between the first and second polymer layers and attaches the first and second polymer layers together.

22 . The apparatus defined in claim 21 wherein the flexible substrate is a polyimide substrate with a thickness of less than 16 microns.

23 . The apparatus defined in claim 21 wherein the flexible substrate is a polyimide substrate with an elasticity of less than 5 GPa.

24 . The apparatus defined in claim 21 wherein the flexible substrate is coated with a coating layer in the bend region that has an elasticity of more than 0.7 GPa.

25 . The apparatus defined in claim 21 wherein the flexible substrate is a polymer substrate and wherein the circuitry in the first area comprises an array of display pixels.

26 . The apparatus defined in claim 21 wherein the flexible substrate is a polymer substrate and wherein the circuitry in the first area comprises an array of sensor structures.

27 . The apparatus defined in claim 21 wherein the first and second polymer layers have respective first and second edges and wherein the second adhesive layer has a protruding portion that extends from between the first and second polymer layers past the first and second edges.

Assignees

• Apple Inc

Inventors

• Zhang Zhen
• Tao Yi
• Drzaic Paul S
• Wurzel Joshua G

Classifications

• Y02E10/549

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• H10K59/873 Primary

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