CN-116863820-B - Foldable display device

Abstract

A foldable display device is provided. The display device includes a display panel including a folded region and non-folded regions at both sides of the folded region, a back plate disposed under the display panel, a first support layer disposed under the back plate, and an opening pattern disposed in a portion corresponding to the folded region, the opening pattern extending through the first support layer, wherein the display panel includes a flexible substrate, a thin film transistor disposed on the flexible substrate and including a gate electrode, a source electrode, a drain electrode, and a semiconductor layer, a planarization layer disposed on the thin film transistor, and a light emitting element disposed on the planarization layer and including an anode electrode, a light emitting unit, and a cathode electrode.

Inventors

• LI SHENGGUI
• Zhao Enai

Assignees

• 乐金显示有限公司

Dates

Publication Date

20260512

Application Date

20201203

Priority Date

20191210

Claims (12)

1. 1. A foldable display device, comprising: A display panel including a folding area and non-folding areas at both sides of the folding area; A back plate disposed under the display panel; a first support layer disposed below the back plate; An impact absorbing layer disposed under the first support layer, and An opening pattern arranged in a portion corresponding to the folded region, the opening pattern extending through the first support layer, Wherein the display panel includes a flexible substrate, a thin film transistor disposed on the flexible substrate and including a gate electrode, a source electrode, a drain electrode, and a semiconductor layer, a planarization layer disposed on the thin film transistor, and a light emitting element disposed on the planarization layer and including an anode, a light emitting unit, and a cathode, Wherein the impact absorbing layer includes a first portion corresponding to the folded region and a second portion corresponding to the unfolded region, and Wherein the modulus of the first portion is greater than the modulus of the second portion.
2. 2. The foldable display device of claim 1, wherein the planarization layer comprises a first planarization layer and a second planarization layer stacked sequentially, and The foldable display device further includes an intermediate electrode connected to the thin film transistor through a contact hole formed in the first planarization layer, and the anode electrode is connected to the intermediate electrode through a contact hole in the second planarization layer.
3. 3. The foldable display device of claim 1, further comprising a bank disposed on the anode and the planarization layer and dividing a region that emits light, and a spacer disposed on the bank and formed of a transparent organic material.
4. 4. The foldable display device of claim 1, further comprising: A cover window positioned in front of the display panel; A touch panel located between the display panel and the cover window, and A second support layer between the back plate and the first support layer.
5. 5. The foldable display device of claim 4, further comprising a plurality of adhesives attaching at least one of the cover window, the touch panel, the display panel, the back sheet, the second support layer, and the first support layer.
6. 6. The foldable display device of claim 5, wherein the plurality of adhesives comprises a first adhesive disposed between the cover window and the touch panel, a second adhesive disposed between the display panel and the back sheet, a third adhesive disposed between the back sheet and the second support layer, and a fourth adhesive disposed between the second support layer and the first support layer.
7. 7. The foldable display device of claim 1, wherein the display panel further comprises a package portion that is provided on the light emitting element and prevents the thin film transistor and the light emitting element from being oxidized or damaged due to moisture.
8. 8. The foldable display device of claim 7, further comprising a touch sensor having electrodes disposed on the encapsulation.
9. 9. A foldable display device according to claim 1, wherein the first portion is formed from a material having a modulus of elasticity that is greater than the modulus of elasticity of the second portion.
10. 10. The foldable display device of claim 1, wherein the first portion and the second portion comprise any one of a material selected from silicone, silicone foam, acrylic foam, polypropylene foam, polyurethane foam, or thermoplastic polyurethane.
11. 11. A foldable display device according to claim 1, wherein the first portion has a thickness of 100 to 1000 μm and a modulus of 1 to 30 MPa.
12. 12. A foldable display device according to claim 1, wherein the second portion has a thickness of 100 to 1000 μm and a modulus of 10 to 1000 KPa.

Description

Foldable display device The present patent application is a divisional application of patent application having a filing date of 2020, 12/3/month, a filing number of 202011397996.6 and a name of "foldable display device". Cross Reference to Related Applications The present application claims the benefit of priority from korean patent application No. 10-2019-0163880, filed on 10 months 12 and 10 in 2019, to the korean intellectual property office, the disclosure of which is incorporated herein by reference. Technical Field The present disclosure relates to a foldable display device, and more particularly, to a foldable display device having improved impact resistance. Background Recently, as society moves toward an informationized society, the field of display devices for processing and displaying a large amount of information is rapidly developed, and accordingly, various flat panel display devices are being developed. Specific examples of such flat panel display devices include liquid crystal display devices (LCDs), field emission display devices (FEDs), electroluminescent display devices (ELDs), organic Light Emitting Diodes (OLEDs), and the like. These flat panel display devices exhibit excellent performance in terms of thinness, lightweight, and low power consumption, and thus are rapidly replacing existing Cathode Ray Tubes (CRTs). Meanwhile, since such a flat panel display device uses a glass substrate to withstand high heat generated during a manufacturing process, it has limitations in terms of reducing weight and thickness and providing flexibility. Accordingly, a flexible display device manufactured to completely maintain display performance even when bent like paper is rapidly becoming a next-generation flat panel display device using a flexible material such as plastic or the like instead of an existing non-flexible glass substrate. Such a flexible display device can be classified into a non-breakable type having high durability by using a plastic thin film transistor substrate instead of glass, a bendable type which is not broken, a crimpable type which can be rolled up, a foldable type which can be folded, and the like. These flexible display devices have advantages in terms of space use and internal design, and can be utilized in various application fields. In particular, recently, in order to realize a large area together with lightness and thinness, weight saving, and miniaturization, foldable display devices capable of being portable in a folded state and displaying images in an unfolded state are being actively studied. The foldable display device can be applied not only to mobile devices such as mobile phones, ultra mobile PCs, electronic books, and electronic newspapers, but also to the fields of various applications such as TVs and monitors. Such a foldable display device includes a display panel for implementing an image, a back plate positioned below the display panel to support the display panel, and a cover window positioned in front of the display panel to protect the display panel. Meanwhile, since the foldable display device should be folded and unfolded, all of the back plate and the cover window and the display panel are configured in a very thin film form, and most of the impact transmitted from the outside is vertically transmitted in such a film form. That is, since the cover window and the back plate are in the form of a thin film, when an impact is applied to the cover window or the back plate from the outside, the impact applied from the outside is directly transmitted to the display panel located between the cover window and the back plate. This in turn causes damage to the display panel, thereby deteriorating the display quality of the display panel. As described above, various structures are being studied and used to reduce the resistance of the common power line. Disclosure of Invention It is an object to be achieved by the present disclosure to provide a foldable display device having improved impact resistance. Another object to be achieved by the present disclosure is to provide a foldable display device capable of preventing degradation of display quality. The objects of the present disclosure are not limited to the above-mentioned objects, and other objects not mentioned above will be clearly understood by those skilled in the art from the following description. According to an aspect of the present disclosure, a foldable display device may include a display panel including a folded region and non-folded regions on both sides of the folded region. The back sheet may be disposed under the display panel, and the first support layer is disposed under the back sheet and has an opening pattern in a portion of the first support layer corresponding to the folding region. The impact absorbing layer may be disposed under the first support layer. The impact absorbing layer may include a first portion corresponding to the folded region and a second portion corresponding to