FLEXIBLE DISPLAY DEVICE WITH REDUCED BEND STRESS WIRES AND MANUFACTURING METHOD FOR THE SAME

• US 20150382446A1
• Filed: 06/30/2014
• Published: 12/31/2015
• Est. Priority Date: 06/30/2014
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Kwon, SeYeoul, Yang, HeeSeok, Youn, Sangcheon, Kim, Sung Woo, Cho, YoonDong, Lee, Saemleenuri
• Granted Patent: US 10,582,612 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 1/1626 with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 1/1637 Details related to the display arrangement, including those related to the mounting of the display in the housing
• CPC Class Codes: G06F 1/1643 the display being associated to a digitizer, e.g. laptops that can be used as penpads details related to the relative motion of the display enclosure with respect to the body enclosure, e.g. to move between laptop and tablet PC configuration G06F1/1615
• CPC Class Codes: G06F 1/1652 the display being flexible, e.g. mimicking a sheet of paper, or rollable
• CPC Class Codes: G06F 2203/04102 Flexible digitiser, i.e. constructional details for allowing the whole digitising part of a device to be flexed or rolled like a sheet of paper
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: H05K 1/0277 Bendability or stretchability details H05K1/038, H05K3/4691 take precedence
• CPC Class Codes: H05K 1/028 Bending or folding regions of flexible printed circuits H05K1/0283 takes precedence
• CPC Class Codes: H05K 1/0283 Stretchable printed circuits
• CPC Class Codes: H05K 1/147 at least one of the printed circuits being bent or folded, e.g. by using a flexible printed circuit H05K1/148 takes precedence
• CPC Class Codes: H05K 1/189 characterised by the use of a flexible or folded printed circuit H05K3/326 takes precedence
• CPC Class Codes: H05K 2201/0195 Dielectric or adhesive layers comprising a plurality of layers, e.g. in a multilayer structure
• CPC Class Codes: H05K 2201/042 Stacked spaced PCBs; Planar parts of folded flexible circuits having mounted components in between or spaced from each other
• CPC Class Codes: H05K 2201/043 Stacked PCBs with their backs attached to each other without electrical connection
• CPC Class Codes: H05K 2201/10128 Display
• CPC Class Codes: H05K 2201/10681 Tape Carrier Package [TCP]; Flexible sheet connector
• CPC Class Codes: H05K 3/4691 Rigid-flexible multilayer circuits comprising rigid and flexible layers, e.g. having in the bending regions only flexible layers
• CPC Class Codes: H10K 2102/311 Flexible OLED
• CPC Class Codes: H10K 59/131 Interconnections, e.g. wiring lines or terminals
• CPC Class Codes: H10K 77/111 Flexible substrates
• CPC Class Codes: Y02E 10/549 : Organic PV cells

Abstract

There is provided a flexible display having a plurality of innovations configured to allow bending of a portion or portions to reduce apparent border size and/or utilize the side surface of an assembled flexible display.

Claims

1. An apparatus, comprising:

a flexible base layer bent along a bend line;

a conductive line on the flexible base layer arranged to extend across the bend line, the conductive line having a trace design with at least two sub-traces splitting and merging back at an angle away from the tangent vector of the curvature; and

one or more insulation layers on at least part of outer surface of the conductive line, said one or more insulation layers having the same trace design as the conductive line and having a greater width than that of the conductive line, wherein the width of the conductive line and the angle in which the sub-traces oriented reduces a length of the insulation layer being aligned to the tangent vector of the curvature.

2. The apparatus of claim 1, wherein the conductive line has a multi-layered structure in which a first conductive layer is interposed between two second conductive layers, and wherein the first and second conductive layers have modulus of less than 330 GPa.

3. The apparatus of claim 2, wherein the trace of the insulation layer includes a plurality of micro-cracks, each capable to focus bending stress thereto.

4. The apparatus of claim 3, wherein the interval in which the conductive line trace splits and merges are not uniform throughout the conductive line.

5. The apparatus of claim 4, wherein the bend line is located at the border of a central portion and a bend portion of the flexible base layer, and wherein the trace of the conductive line splits and merges at a lesser angle at the bend line than in the bend portion.

6. The apparatus of claim 5, wherein the conductive line splits into two sub-traces and merges back, forming a chain of diamond trace design.

7. The apparatus of claim 5, wherein the conductive line splits and merges in more than two sub-traces, thereby forming a grid of diamond trace design.

8. The apparatus of claim 6, wherein the conductive line has expanded width at angled corners of the trace design.

9. The apparatus of claim 7, wherein the width of the conductive line at the angled corners is no greater than 5 um.

10. The apparatus of claim 8, wherein the width of the conductive line between each joint of the trace design is in a range of about 4 um to 4.5 um.

11. A flexible display, comprising:

a wire trace having a design that focuses bending stress to one or more stress points; and

a conductive line of the wire trace having an increased width at said one or more stress points.

12. The flexible display of claim 11, wherein the wire trace is disposed in the bend allowance area, and arranged to extend towards the bending direction by splitting and merging at one or more intervals.

13. The flexible display of claim 12, wherein the wire trace splits and merges at an angle away from the bending direction to minimize a length of an insulation layer of the wire trace being aligned to the bending direction.