Foldable display device

Abstract

The present disclosure relates to a foldable display device, which belongs to the field of display. The foldable display device includes a flexible display panel, a flexible cover plate and a flexible circuit board. The flexible display panel has a first foldable area and a first side edge, the first foldable area includes a first sub-area, and a portion of the first side edge is a boundary of the first sub-area. The flexible cover plate is bonded to the first surface of the flexible display panel, and the flexible cover plate has a second foldable area. The orthographic projection of the second foldable area on the first surface is located inside the first foldable area. The second foldable area is bonded to the first foldable area, and the orthographic projection of the second foldable area on the first surface does not overlap with the first sub-area. The flexible circuit board is bound to the first side edge, and the orthographic projection of the flexible circuit board on the first surface does not overlap with the orthographic projection of the first foldable area on the first surface, which improves the problem of wrinkles generated when the flexible cover plate is bent.

Description

Technical Field

[0001] The present disclosure relates to the field of display, and in particular to a foldable display device. Background Art

[0002] The rise of foldable display devices has enabled the rapid development of foldable display technology. The foldable display device includes a flexible display panel, a flexible cover plate and a flexible printed circuit (FPC). The flexible cover plate is bonded to the surface of the flexible display panel to protect the surface of the flexible display panel. The first side of the flexible display panel is bound to the flexible printed circuit board, and the flexible printed circuit board is bent from the front of the flexible display panel to the back of the flexible display panel. The flexible cover plate will shield the flexible printed circuit board. Summary of the invention

[0003] The embodiment of the present disclosure provides a foldable display device, which improves the problem of wrinkles generated when the flexible cover is bent. The technical solution is as follows:

[0004] The present disclosure provides a foldable display device, comprising: a flexible display panel, having a first foldable area and a first side edge, the first foldable area including a first sub-area, and a portion of the first side edge being a boundary of the first sub-area; a flexible cover plate, bonded to the first surface of the flexible display panel, the flexible cover plate having a second foldable area, the orthographic projection of the second foldable area on the first surface being located inside the first foldable area, the second foldable area being bonded to the first foldable area, and the orthographic projection of the second foldable area on the first surface not overlapping with the first sub-area; and a flexible circuit board, bound to the first side edge, the orthographic projection of the flexible circuit board on the first surface not overlapping with the second foldable area.

[0005] In an implementation of the embodiment of the present disclosure, the edge of the flexible cover has a notch, and the notch is located in the extension direction of the second foldable area; the flexible circuit board includes two first parts, and in the extension direction of the first side, the two first parts are respectively located on both sides of the first foldable area; on the first surface, the orthographic projection of the two first parts at least partially overlaps with the orthographic projection of the parts of the flexible cover located on both sides of the notch.

[0006] In an implementation of the embodiment of the present disclosure, the width of the notch is greater than or equal to the width of the second foldable area, and the width of the notch and the width of the second foldable area are both dimensions in the extension direction of the first side.

[0007] In an implementation manner of the embodiment of the present disclosure, an orthographic projection of the flexible circuit board on the first surface does not overlap with an orthographic projection of the flexible cover on the first surface.

[0008] In one implementation of the embodiment of the present disclosure, the foldable display device also includes: a shell, including an annular baffle, the annular baffle surrounds the edge of the flexible display panel, and the annular baffle and the flexible cover are located on the same side of the flexible display panel; there is a gap between the annular baffle and the flexible display panel, the flexible circuit board is located in the gap, and on the first surface, the orthographic projection of the flexible circuit board is located within the orthographic projection of the annular baffle.

[0009] In an implementation manner of the embodiment of the present disclosure, a surface of the flexible cover plate away from the flexible display panel is flush with a surface of the annular baffle away from the flexible display panel.

[0010] In an implementation of the embodiment of the present disclosure, the inner edge of the annular baffle is in contact with the edge of the flexible cover.

[0011] In one implementation of the embodiment of the present disclosure, the foldable display device also includes: a first adhesive layer, located between the flexible display panel and the flexible cover plate, the orthographic projection of the first adhesive layer on the first surface does not overlap with the orthographic projection of the flexible circuit board on the first surface, on the side where the first side edge is located, the edge of the first adhesive layer protrudes from the edge of the flexible cover plate, the first adhesive layer and the flexible cover plate form a first step, and the annular baffle has a second step that matches the first step.

[0012] In an implementation of the embodiment of the present disclosure, the width of the step surface of the first step ranges from 0.2 mm to 0.5 mm, and the width of the step surface is the dimension in a direction perpendicular to the extension direction of the first side and parallel to the first surface.

[0013] In one implementation of the embodiment of the present disclosure, the shell also includes: a bottom plate, opposite to the annular baffle; a side plate, connected between the outer edge of the bottom plate and the outer edge of the annular baffle, the annular baffle, the bottom plate and the side plate form a accommodating space, and the flexible display panel is located in the accommodating space.

[0014] In one implementation of the embodiment of the present disclosure, the foldable display device also includes: a touch panel, located between the flexible display panel and the flexible cover plate, the touch panel having a third foldable area and a second side, the third foldable area including a second sub-area, and a portion of the second side being a boundary of the second sub-area; the orthographic projection of the second foldable area on the first surface is located inside the third foldable area, and the orthographic projection of the second foldable area on the first surface does not overlap with the orthographic projection of the second sub-area on the first surface; a touch flexible circuit board, bound to the second side, the orthographic projection of the touch flexible circuit board on the first surface does not overlap with the orthographic projection of the third foldable area on the first surface.

[0015] In an implementation manner of the embodiment of the present disclosure, two opposite sides of the touch panel are bound to the touch flexible circuit board.

[0016] In one implementation of the embodiment of the present disclosure, the foldable display device also includes: a second adhesive layer, located between the touch panel and the flexible display panel, the orthographic projection of the second adhesive layer on the first surface and the orthographic projection of the touch flexible circuit board on the first surface do not overlap on the side where the second side is located, and the edge of the flexible display panel protrudes from the edge of the second adhesive layer.

[0017] In one implementation of the embodiment of the present disclosure, the flexible display panel has a second surface, the second surface and the first surface are two opposite surfaces of the support plate, and the foldable display device also includes: a support plate, having a third surface and a fourth surface relative to each other, the third surface is attached to the second surface, and the flexible circuit board is bent to the fourth surface of the support plate.

[0018] In one implementation of the embodiment of the present disclosure, the support plate has a groove, and the groove extends from the edge of the fourth surface to the middle of the fourth surface; the foldable display device also includes: a driving circuit located in the groove, and the flexible circuit board is electrically connected to the driving circuit.

[0019] The beneficial effects brought by the technical solution provided by the embodiments of the present disclosure include at least:

[0020] In the disclosed embodiment, since the first sub-area of ​​the first foldable area does not overlap with the orthographic projection of the second foldable area on the first surface, the orthographic projection of the flexible circuit board on the first surface does not overlap with the second foldable area. In other words, the second foldable area of ​​the flexible cover is retracted so that the second foldable area of ​​the flexible cover is bonded to the first foldable area. When the flexible cover is bent, the folding area of ​​the flexible cover is subjected to the adhesive force and will not be wrinkled due to the bending, thereby improving the problem of wrinkles when the flexible cover is bent. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 is a top view of a foldable display device provided by an embodiment of the present disclosure in a flat state;

[0023] Figure 2 is a side view of a foldable display device in a folded state provided by an embodiment of the present disclosure;

[0024] Figure 3 yes Figure 1 Schematic diagram of the cross section of the AA surface;

[0025] Figure 4 is a top view of a flexible display panel provided by an embodiment of the present disclosure;

[0026] Figure 5 is a top view of a flexible cover provided by an embodiment of the present disclosure;

[0027] Figure 6 is a top view of an assembly of a flexible display panel, a flexible cover plate, and a flexible circuit board provided by an embodiment of the present disclosure;

[0028] Figure 7 is a top view of another flexible cover provided by an embodiment of the present disclosure;

[0029] Figure 8 is a top view of another assembly of a flexible display panel, a flexible cover plate, and a flexible circuit board provided by an embodiment of the present disclosure;

[0030] Fig. 9 is a top view of another flexible cover provided by an embodiment of the present disclosure;

[0031] Fig.10is a top view of another assembly of a flexible display panel, a flexible cover plate, and a flexible circuit board provided by an embodiment of the present disclosure;

[0032] Fig.11 It is a structural diagram of a foldable display device provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0034] In the related art, the flexible circuit board is bound to the first side of the flexible display panel, and the area in the flexible display panel for binding the flexible circuit board is not bonded to the flexible cover plate, that is, the folding area of ​​the flexible cover plate has a portion that is not bonded to the flexible display panel. For an inward-folding foldable display device (the flexible cover plate is on the inside after folding), when the foldable display device is bent, the portion of the flexible cover plate that is not bonded to the flexible display panel will also bend, and the flexible cover plate will be squeezed after bending, resulting in wrinkles in the portion of the flexible cover plate that is not bonded to the flexible display panel and is bent.

[0035] Figure 1 is a top view of a foldable display device provided by an embodiment of the present disclosure in a flat state. Figure 1 The foldable display device has a first planar display area 11, a bendable display area 12, and a second planar display area 13 connected in sequence along a first direction a. When the foldable display device is in a planar state, the surface of the first planar display area 11, the surface of the bendable display area 12, and the surface of the second planar display area 13 are all in the same plane. When the bendable display area 12 is bent, the display device can be changed from a planar state to a bend state, and at this time, the first planar display area 11 and the second planar display area 13 are opposite to each other.

[0036] The foldable display device provided in the embodiment of the present disclosure may be an inward-folding foldable display device. Figure 2 is a side view of a foldable display device provided by an embodiment of the present disclosure in a folded state. Figure 2 The foldable display device includes a stacked flexible display panel 10 and a flexible cover 20. When the inward-folding foldable display device is in a folded state, the flexible cover 20 is located on the inner side of the fold, so that the flexible cover 20 is subjected to bending pressure. The material of the flexible cover 20 is relatively soft and wrinkles are easily generated when subjected to pressure.

[0037] In other implementations, the foldable display device may be an outward-folding foldable display device. When the outward-folding foldable display device is in a folded state, the flexible cover plate is on the outer side of the bend.

[0038] Figure 3 yes Figure 1 Schematic diagram of the cross section of the AA surface. Figure 3 The foldable display device includes: a flexible display panel 10, a flexible cover plate 20 and a flexible circuit board 30. The flexible display panel 10 has a first foldable area 101 and a first side 104, the first foldable area 101 includes a first sub-area 103, and a part of the first side 104 is the boundary of the first sub-area 103. The flexible cover plate 20 is bonded to the first surface 102 of the flexible display panel 10, and the flexible cover plate 20 has a second foldable area 201, the orthographic projection of the second foldable area 201 on the first surface 102 is located inside the first foldable area 101, the second foldable area 201 is bonded to the first foldable area 101, and the orthographic projection of the second foldable area 201 on the first surface 102 does not overlap with the first sub-area 103. The flexible circuit board 30 is bound to the first side 104 of the flexible display panel 10, and the orthographic projection of the flexible circuit board 30 on the first surface 102 does not overlap with the second foldable area 201.

[0039] In the disclosed embodiment, since the first sub-area of ​​the first foldable area does not overlap with the orthographic projection of the second foldable area on the first surface, the orthographic projection of the flexible circuit board on the first surface does not overlap with the second foldable area. In other words, the second foldable area of ​​the flexible cover is retracted so that the second foldable area of ​​the flexible cover is bonded to the first foldable area. When the flexible cover is bent, the folding area of ​​the flexible cover is subjected to the adhesive force and will not be wrinkled due to the bending, thereby improving the problem of wrinkles when the flexible cover is bent.

[0040] In the embodiment of the present disclosure, the orthographic projection of the flexible circuit board 30 on the first surface 102 does not overlap with the first foldable area 101, that is, the flexible circuit board 30 is not bound to the bent part of the flexible display panel 10, thereby preventing the flexible circuit board 30 from being damaged during the bending process.

[0041] In the related art, since the flexible cover plate 20 generates wrinkles when being bent, the flexible cover plate 20 may be separated from the flexible display panel 10. The foldable display panel provided in the embodiment of the present disclosure improves the problem of wrinkles generated when the flexible cover plate 20 is bent, and can also effectively improve the problem of separation of the flexible cover plate 20 from the flexible display panel 10.

[0042] Figure 4 is a top view of a flexible display panel provided by an embodiment of the present disclosure. Figure 4, the first foldable area 101 is rectangular, and the boundary of the first sub-area 103 is a part of the first side 104. The flexible display panel 10 also has a first plane area 106 and a second plane area 107. Along the first direction a, the first plane area 106 and the second plane area 107 are respectively located on both sides of the first foldable area 101. Among them, the first foldable area 101 is opposite to the bendable display area 12. The first plane area 106 is opposite to the first plane display area 11, and the second plane area 107 is opposite to the second plane display area 13.

[0043] like Figure 4 As shown, the first foldable region 101 further includes a third sub-region 108. The third sub-region 108 and the first sub-region 103 form the first foldable region 101. And on the first surface 102, the orthographic projection of the second foldable region 201 coincides with the third sub-region 108.

[0044] In the embodiment of the present disclosure, the flexible display panel 10 may be a flexible OLED display panel.

[0045] Figure 5 is a top view of a flexible cover provided by an embodiment of the present disclosure. Figure 5 The flexible cover 20 further has a third plane area 204 and a fourth plane area 205. Along the first direction a, the third plane area 204 and the fourth plane area 205 are respectively located on both sides of the second foldable area 201. The second foldable area 201 is opposite to the bendable display area 12, the third plane area 204 is opposite to the first plane display area 11, and the fourth plane area 205 is opposite to the second plane display area 13.

[0046] In the disclosed embodiment, the flexible cover plate 20 may be a polyimide (PI) cover plate or a colorless polyimide (CPI) cover plate, so as to ensure the flexibility and transparency of the flexible cover plate 20 .

[0047] See again Figure 5 The edge of the flexible cover plate 20 has a notch 202, and the notch 202 is located in the extension direction b of the second foldable area 201, so that the flexible cover plate 20 is in a "concave" shape. Figure 5 In the embodiment, the second foldable region 201 is in a rectangular shape, the notch 202 is in a rounded rectangular shape, and one side of the second foldable region 201 is a part of one side of the notch 202. Arranging the notch 202 in a rounded rectangular shape can reduce the stress concentration phenomenon at the edge of the notch 202.

[0048] Figure 6: is a top view of a flexible display panel, a flexible cover plate and a flexible circuit board provided by an embodiment of the present disclosure. Figure 6 The flexible display panel 10 shown is Figure 4 The flexible display panel 10 shown, Figure 6 The flexible cover 20 shown is Figure 5 The flexible cover 20 shown. Figure 6 The flexible circuit board 30 includes two first parts 301. In the first direction a, the two first parts 301 are respectively located on both sides of the first foldable area 101. On the first surface 102, the orthographic projections of the two first parts 301 at least partially overlap with the orthographic projections of the parts of the flexible cover plate 20 located on both sides of the notch 202.

[0049] When the flexible cover plate 20 is bent, the flexible cover plate 20 is subjected to a large bending pressure in the second foldable area 201. Therefore, the flexible cover plate 20 needs to be bonded to the flexible display panel 10, so that the flexible cover plate 20 is wrinkled due to the bending pressure. However, the bending pressure on the flexible cover plate 20 in the third plane area 204 and the fourth plane area 205 is very small and can be ignored. Therefore, the flexible cover plate 20 generally does not generate wrinkles in the third plane area 204 and the fourth plane area 205.

[0050] In the embodiment of the present disclosure, the flexible cover plate 20 is partially retracted in the second foldable area 201, so that the second foldable area 201 of the flexible cover plate 20 is completely bonded to the flexible display panel 10, which not only ensures that no wrinkles are generated when the flexible cover plate 20 is bent, but also ensures that the area of ​​the flexible cover plate 20 is larger than that of the entire side of the flexible cover plate 20, and can protect the surface of the flexible display panel 10. At the same time, the orthographic projection of the flexible circuit board 30 partially overlaps with the orthographic projection of the flexible cover plate 20, so the third plane area 204 and the fourth plane area 205 of the flexible cover plate 20 can block the flexible circuit board 30, and protect the flexible circuit board 30 and the flexible display panel 10.

[0051] In a possible implementation, the flexible circuit board 30 includes at least two circuit boards. In the first direction a, the at least two circuit boards are respectively located on both sides of the first foldable region 101. All circuit boards located on one side of the first foldable region 101 are a first part 301, and all circuit boards located on the other side of the first foldable region 101 are another first part 301. In another possible implementation, the flexible circuit board 30 includes a circuit board. For example, the circuit board is in a "Y" shape. The Y-shaped circuit board has two branches. One end of the two branches is respectively bound to the flexible display panel 10, and the other ends of the two branches are connected. The two branches of the flexible circuit board 30 are two first parts 301.

[0052] See again Figure 5 and Figure 6 , the width L1 of the notch 202 is greater than the width L2 of the second foldable area 201, and the width L1 of the notch 202 and the width L2 of the second foldable area 201 are both dimensions in the extension direction of the first side 104. The extension direction of the first side 104 is consistent with the first direction a. At this time, a part of the two first portions 301 may be located in the notch 202.

[0053] In the disclosed embodiment, the width L1 of the notch 202 may be greater than the width L2 of the second foldable region 201 , so as to prevent the flexible cover 20 from wrinkling or warping at the junction of the notch 202 and the second foldable region 201 .

[0054] In other implementations, the width L1 of the notch 202 may be equal to the width L2 of the second foldable area 201, so that the width L1 of the notch 202 is minimized, and the area of ​​the flexible cover 20 is maximized, further improving the protective effect of the flexible cover 20 on the surface of the flexible display panel 10. At this time, on the first surface 102, the orthographic projections of the two first portions 301 are located inside the orthographic projections of the portions of the flexible cover 20 located on both sides of the notch 202.

[0055] Exemplarily, the difference between the width of the notch 202 and the width of the second foldable region 201 ranges from 0 mm to 5 mm.

[0056] In the embodiment of the present disclosure, the notch 202 may be a right-angled rectangle or a trapezoid.

[0057] Figure 5 and Figure 6 The flexible cover 20 shown has a notch 202. Figure 6 A flexible circuit board 30 is bound to one side of the flexible display panel 10. In other implementations, the flexible circuit board 30 can be bound to two or more sides of the flexible display panel 10.

[0058] Figure 7 FIG. 1 is a top view of another flexible cover provided by an embodiment of the present disclosure. Figure 7 The edge of the flexible cover plate 20 has two notches 202 , and in the extension direction b of the second foldable area 201 , the two notches 202 are respectively located on both sides of the second foldable area 201 .

[0059] Figure 8 : is a top view of another flexible display panel, a flexible cover plate and a flexible circuit board provided by an embodiment of the present disclosure. Figure 8 The flexible display panel 10 shown is Figure 4 The flexible display panel 10 shown, Figure 8 The flexible cover 20 shown is Figure 7The flexible cover 20 shown. Figure 8 The flexible display panel 10 has two first side edges 104 , and the two first side edges 104 are both bound with a flexible circuit board 30 .

[0060] Figure 5 and Figure 8 The flexible cover 20 shown has a notch 202, and the orthographic projection of the flexible circuit board 30 partially overlaps with the orthographic projection of the flexible cover 20. In other implementations, the flexible cover 20 may not have a notch, and the orthographic projection of the flexible circuit board 30 does not overlap with the orthographic projection of the flexible cover 20.

[0061] Fig. 9 FIG. 1 is a top view of another flexible cover provided by an embodiment of the present disclosure. Fig. 9 , the flexible cover plate 20 has no gap. And Fig. 9 The size of the second foldable area 201 in the flexible cover 20 is shown as Figure 5 The second foldable area 201 in the flexible cover 20 shown has the same size, and the edges of the third planar area 204 and the fourth planar area 205 are retracted so that the edges of the third planar area 204 and the fourth planar area 205 are flush with the edge of the second foldable area 201.

[0062] Fig.10 FIG. 1 is a top view of another flexible display panel, a flexible cover plate, and a flexible circuit board provided by an embodiment of the present disclosure. Fig.10 , the orthographic projection of the flexible circuit board 30 on the first surface 102 does not overlap with the orthographic projection of the flexible cover plate 20 on the first surface 102. Fig.10 The flexible display panel 10 shown is Figure 4 The flexible display panel 10 shown, Fig.10 The flexible cover 20 shown is Fig. 9 The flexible cover 20 is shown.

[0063] In the disclosed embodiment, the entire side of the flexible cover plate 20 is retracted so that the entire surface of the flexible cover plate 20 is bonded to the flexible display panel 10. When the flexible cover plate 20 is bent, the flexible cover plate 20 is affected by the adhesive force and will not produce wrinkles due to bending.

[0064] See again Figure 3The foldable display device further includes: a housing 40. The housing 40 includes an annular baffle 401, which surrounds the edge of the flexible display panel 10, and the annular baffle 401 and the flexible cover plate 20 are located on the same side of the flexible display panel 10, and there is a gap 402 between the annular baffle 401 and the flexible display panel 10, and the flexible circuit board 30 is located in the gap 402. On the first surface 102, the orthographic projection of the flexible circuit board 30 is located in the orthographic projection of the annular baffle 401. The housing 40 can be a middle frame or a shell of the foldable display device. Among them, the part where the flexible circuit board 30 is bound to the flexible display panel 10 is located in the gap 402.

[0065] Since the flexible cover plate 20 may not be able to completely cover the flexible circuit board 30 after being retracted, a part of the flexible circuit board 30 may be exposed, affecting the appearance of the display device. At the same time, the exposed flexible circuit board 30 is not blocked and is more susceptible to damage than the blocked part. In the embodiment of the present disclosure, the housing 40 is arranged, and the gap 402 between the annular baffle 401 and the flexible display panel 10 is used to arrange the flexible circuit board 30, and the orthographic projection of the flexible circuit board 30 is located within the orthographic projection of the annular baffle 401. The annular baffle 401 can block the flexible circuit board 30 to avoid affecting the appearance of the display device, and at the same time protect the flexible circuit board 30 to reduce the possibility of damage to the flexible circuit board 30. Since the annular baffle 401 belongs to the housing 40, the material strength is relatively high, and wrinkles are not easily generated when bent.

[0066] In the disclosed embodiment, the housing 40 is a metal housing to ensure the strength of the housing 40. When the foldable display device is bent, the housing 40 will also bend. Metal has certain bending properties and high material strength, and is not easy to wrinkle when bent.

[0067] Optionally, in other implementations, the housing 40 is a plastic housing. The density of plastic is low, which can reduce the weight of the foldable display device.

[0068] See again Figure 3 The housing 40 further includes: a bottom plate 404 and a side plate 405. The bottom plate 404 is opposite to the annular baffle 401. The side plate 405 is connected between the outer edge of the bottom plate 404 and the outer edge of the annular baffle 401, and the bottom plate 404 and the side plate 405 form an accommodating space 406, and the flexible display panel 10 is located in the accommodating space 406. Usually, the housing 40 includes a plurality of side plates 405, and the plurality of side plates 405 are respectively connected to the bottom plate 404 and the side plates 405.

[0069] In the embodiment of the present disclosure, the annular baffle 401, the bottom plate 404 and the side plate 405 form an accommodating space 406. The flexible display panel 10 is placed in the accommodating space 406 to protect the side of the flexible display panel 10 and prevent the side of the flexible display panel 10 from being bumped and damaged.

[0070] See again Figure 3 , a surface 206 of the flexible cover plate 20 away from the flexible display panel 10 is flush with a surface 411 of the annular baffle 401 away from the flexible display panel 10 .

[0071] In the embodiment of the present disclosure, the surface 411 of the annular baffle 401 is flush with the surface 206 of the flexible cover plate 20, ensuring the flatness of the surface of the foldable display device. At the same time, compared with the related art, in which the annular baffle 401 is arranged on the flexible cover plate 20, the structure of the foldable display device provided by the embodiment of the present disclosure can reduce the thickness of the housing 40, and also reduce the thickness of the foldable display device, which is conducive to the thinness of the foldable display device.

[0072] See again Figure 3 The inner edge of the annular baffle 401 is in contact with the edge of the flexible cover plate 20 .

[0073] In the embodiment of the present disclosure, the inner edge of the annular baffle 401 fits with the edge of the flexible cover plate 20, so that the annular baffle 401 and the flexible cover plate 20 can completely cover the surface of the flexible display panel 10, thereby improving the surface protection effect of the flexible display panel 10.

[0074] See again Figure 3 The foldable display device further includes: a first adhesive layer 50. The first adhesive layer 50 is located between the flexible display panel 10 and the flexible cover plate 20. The first adhesive layer 50 bonds the flexible display panel 10 and the flexible cover plate 20 together.

[0075] Exemplarily, the first adhesive layer 50 may be an optically clear adhesive (OCA) layer or a foam adhesive layer.

[0076] In the disclosed embodiment, the orthographic projection of the first adhesive layer 50 on the first surface 102 does not overlap with the orthographic projection of the flexible circuit board 30 on the first surface 102 , so as to prevent the first adhesive layer 50 from covering the flexible circuit board 30 and affecting the performance of the flexible circuit board 30 .

[0077] See again Figure 3 On the side where the first side edge 104 is located, the edge of the first adhesive layer 50 protrudes from the edge of the flexible cover plate 20 , the first adhesive layer 50 and the flexible cover plate 20 form a first step 203 , and the annular baffle 401 has a second step 403 matching the first step 203 .

[0078] In the embodiment of the present disclosure, the first adhesive layer 50 and the flexible cover plate 20 form a first step 203, so the step surface 231 of the first step 203 is a part of the surface of the first adhesive layer 50 and is also sticky. The step surface 431 of the second step 403 fits with the step surface 231 of the first step 203, thereby bonding the annular baffle 401 to the flexible display panel 10, thereby increasing the stability of the shell 40.

[0079] In the embodiment of the present disclosure, for Figure 5 and Figure 6 The flexible cover plate 20 shown in the figure and the second foldable area 201 of the flexible cover plate 20 are both bonded to the flexible cover plate 20 through the first adhesive layer 50, and the portion of the flexible cover plate 20 opposite to the flexible circuit board 30 is not bonded to the flexible cover plate 20 through the first adhesive layer 50. That is, only at the notch 202, the edge of the first adhesive layer 50 protrudes from the edge of the flexible cover plate 20.

[0080] for Fig. 9 and Fig.10 The flexible cover plate 20 shown is bonded to the flexible cover plate 20 by the first adhesive layer 50. On the side where the first side edge 104 is located, the edge of the entire side edge of the first adhesive layer 50 protrudes from the edge of the flexible cover plate 20.

[0081] In the embodiment of the present disclosure, the width of the step surface 231 of the first step 203 ranges from 0.2 mm to 0.5 mm, and the width of the step surface 231 is the dimension in a direction perpendicular to the extension direction of the first side 104 and parallel to the first surface 102 .

[0082] The width of the step surface 231 of the first step 203 is limited to 0.2 mm to 0.5 mm, which can ensure that the step surface 231 of the first step 203 is bonded to the annular baffle 401 and leave enough area on the first side 104 of the flexible display panel 10 to be bound to the flexible circuit board 30.

[0083] See again Figure 3, the foldable display device further includes: a touch panel (Touch Panel, TP) 60 and a touch flexible printed circuit (Touch Flexible Printed Circuit, TFPC) 70. The touch panel 60 is located between the flexible display panel 10 and the flexible cover 20, and the touch panel 60 has a third foldable area 601 and a second side 603, the third foldable area 601 includes a second sub-area 602, and a part of the second side 603 is the boundary of the second sub-area 602. The orthographic projection of the second foldable area 201 on the first surface 102 is located inside the orthographic projection of the third foldable area 601 on the first surface 102, and the orthographic projection of the second foldable area 201 on the first surface 102 does not overlap with the orthographic projection of the second sub-area 602 on the first surface 102. The touch flexible printed circuit 70 is bound to the second side 603 of the touch panel 60, and the orthographic projection of the touch flexible printed circuit 70 on the first surface 102 does not overlap with the orthographic projection of the third foldable area 601 on the first surface 102.

[0084] It should be noted that in Figure 3 In the cross-sectional view of FIG. 1 , the third foldable region 601 overlaps with the first foldable region 101, and the second sub-region 602 overlaps with the first sub-region 103. However, the first foldable region 101 and the first sub-region 103 belong to the flexible display panel 10. The third foldable region 601 and the second sub-region 602 belong to the touch panel 60.

[0085] The touch panel 60 and the touch flexible circuit board 70 are arranged in the foldable display device, so that the foldable display device can realize the touch function.

[0086] At the same time, the orthographic projection of the second sub-area 602 of the third foldable area 601 on the first surface 102 does not overlap with the orthographic projection of the second foldable area 201 on the first surface 102, and the orthographic projection of the touch flexible circuit board 70 on the first surface 102 does not overlap with the orthographic projection of the third foldable area 601 on the first surface 102, that is, the folding area of ​​the flexible cover 20 is bonded to the touch panel 60, and the folding area of ​​the flexible cover 20 does not extend to the area where the touch panel 60 is bound to the touch flexible circuit board 70, and the area where the touch panel 60 is bound to the touch flexible circuit board 70 cannot be bonded to the flexible cover 20. When the flexible cover 20 is bent, the folded area of ​​the flexible cover 20 will be affected by the adhesive force, and wrinkles will not be generated due to the bending, thereby improving the problem of wrinkles generated by the flexible cover 20 when bending.

[0087] In the embodiment of the present disclosure, the orthographic projection of the touch flexible circuit board 70 on the first surface 102 does not overlap with the orthographic projection of the third foldable area 601 on the first surface 102, that is, the touch flexible circuit board 70 is not bound to the folded part of the touch panel 60, thereby preventing the touch flexible circuit board 70 from being damaged during the bending process.

[0088] See again Figure 3 , two opposite surfaces of the touch panel 60 are bound to the touch flexible circuit board 70 , thereby increasing the binding area between the touch panel 60 and the touch flexible circuit board 70 .

[0089] See again Figure 3 The foldable display device further includes: a second adhesive layer 80. The second adhesive layer 80 is located between the touch panel 60 and the flexible display panel 10, and the second adhesive layer 80 bonds the flexible display panel 10 and the touch panel 60 together, and at this time, the first adhesive layer 50 bonds the touch panel 60 and the flexible cover plate 20 together.

[0090] Exemplarily, the second adhesive layer 80 may be an optical adhesive layer or a foam adhesive layer.

[0091] In the disclosed embodiment, the orthographic projection of the second adhesive layer 80 on the first surface 102 does not overlap with the orthographic projection of the touch flexible circuit board 70 on the first surface 102 , so as to prevent the second adhesive layer 80 from covering the touch flexible circuit board 70 and affecting the performance of the touch flexible circuit board 70 .

[0092] See again Figure 3 At the second side 603 , the edge of the touch panel 60 protrudes out of the edge of the second glue layer 80 .

[0093] In the embodiment of the present disclosure, two opposite sides of the touch panel 60 are bound to the touch flexible circuit board 70, and the second adhesive layer 80 is located between the touch panel 60 and the flexible display panel 10. On the side where the second side edge 603 is located, the size of the second adhesive layer 80 is reduced, leaving enough area in the touch panel 60 for binding with the touch flexible circuit board 70, thereby facilitating the binding of the touch panel 60 and the touch flexible circuit board 70.

[0094] See again Figure 3 The foldable display device further includes a polarizer (POL) 100. The polarizer 100 is located between the flexible display panel 10 and the second adhesive layer 80. The polarizer 100 is used to change the polarization direction of polarized light to ensure that the foldable display device can display images.

[0095] like Figure 3 As shown, due to the inward contraction of the second adhesive layer 80 , the edge of the polarizer 100 on the side where the second side edge 603 is located protrudes from the edge of the second adhesive layer 80 , that is, the edge of the second adhesive layer 80 is contracted.

[0096] In the embodiment of the present disclosure, in the extension direction b of the second foldable area 201, the length of the edge of the polarizer 100 protruding from the edge of the second adhesive layer 80 is in the range of 0.2 mm to 0.5 mm, which is convenient for binding the touch panel 60 and the touch flexible circuit board 70, and prevents the edge of the second adhesive layer 80 from shrinking too much, resulting in the area of ​​the second adhesive layer 80 being too small, affecting the bonding of the touch panel 60 and the flexible display panel 10.

[0097] See again Figure 3 In the extension direction b of the second foldable area 201 , there is a gap between the flexible circuit board 30 and the polarizer 100 , which is a manufacturing tolerance.

[0098] Figure 3 In the film layer diagram shown, the edge of the first adhesive layer 50 is not flush with the edge of the flexible cover plate 20 , and the edge of the polarizer 100 is not flush with the edge of the second adhesive layer 80 .

[0099] Fig.11 is a schematic diagram of the structure of a foldable display device provided by an embodiment of the present disclosure. Fig.11 , Fig.11 The structure shown in Figure 3 The difference is that the edge of the first adhesive layer 50 is flush with the edge of the flexible cover plate 20 , and the edge of the polarizer 100 is flush with the edge of the second adhesive layer 80 .

[0100] In the embodiment of the present disclosure, after the flexible display panel 10, the polarizer 100, the second adhesive layer 80, the touch panel 60, the first adhesive layer 50 and the flexible cover plate 20 are bonded together, on the side where the flexible circuit board 30 and the touch flexible circuit board 70 are not arranged, the flexible display panel 10, the polarizer 100, the second adhesive layer 80, the touch panel 60, the first adhesive layer 50 and the flexible cover plate 20 can be cut by die cutting, so that on the side of the foldable display device where the flexible circuit board 30 and the touch flexible circuit board 70 are not arranged, the edge of the flexible display panel 10, the edge of the polarizer 100, the edge of the second adhesive layer 80, the edge of the touch panel 60, the edge of the first adhesive layer 50 and the edge of the flexible cover plate 20 are flush.

[0101] See again Figure 3 and Fig.11 The flexible display panel 10 also has a second surface 105, and the second surface 105 and the first surface 102 are two opposite surfaces of the flexible display panel 10. The foldable display device also includes: a support plate 90. The support plate 90 has a third surface 901 and a fourth surface 902 opposite to each other, the third surface 901 is attached to the second surface 105, and the flexible circuit board 30 is bent to the fourth surface 902 of the support plate 90.

[0102] In the embodiment of the present disclosure, a support plate 90 is arranged to support the flexible display panel 10 to ensure the shape of the foldable display device in a flat state.

[0103] See again Figure 3 and Fig.11 The support plate 90 has a groove 903, and the groove 903 extends from the edge of the fourth surface 902 to the middle of the fourth surface 902. The foldable display device also includes a driving circuit located on the groove 903, and the flexible circuit board 30 is electrically connected to the driving circuit.

[0104] In the embodiment of the present disclosure, the groove 903 extends from the edge of the fourth surface 902 to the middle of the fourth surface 902 to form a third step 904, and the driving circuit is arranged in the groove 903. The parts of the flexible circuit board 30 and the touch flexible circuit board 70 electrically connected to the driving circuit are also located in the groove 903, thereby reducing the thickness of the foldable display device.

[0105] Exemplarily, the support plate 90 is a metal support plate to ensure the support performance and bending performance of the support plate 90 .

[0106] The above description is only an optional embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A foldable display device, characterized in that: The foldable display device comprises: A flexible display panel (10) comprising a first foldable area (101) and a first side edge (104), wherein the first foldable area (101) comprises a first sub-area (103), and a portion of the first side edge (104) is a boundary of the first sub-area (103); A flexible cover plate (20) bonded to a first surface (102) of the flexible display panel (10), the flexible cover plate (20) having a second foldable region (201), an orthographic projection of the second foldable region (201) on the first surface (102) being located inside the first foldable region (101), the second foldable region (201) being bonded to the first foldable region (101), and an orthographic projection of the second foldable region (201) on the first surface (102) not overlapping with the first sub-region (103); a flexible circuit board (30) bound to the first side edge (104), wherein an orthographic projection of the flexible circuit board (30) on the first surface (102) does not overlap with the second foldable area (201); The foldable display device further includes: A housing (40) comprising an annular baffle (401), wherein the annular baffle (401) surrounds an edge of the flexible display panel (10), and the annular baffle (401) and the flexible cover plate (20) are located on the same side of the flexible display panel (10); There is a gap (402) between the annular baffle (401) and the flexible display panel (10), the flexible circuit board (30) is located in the gap (402), and on the first surface (102), the orthographic projection of the flexible circuit board (30) is located within the orthographic projection of the annular baffle (401); The flexible display panel (10) is a flexible OLED display panel.

2. The foldable display device according to claim 1, characterized in that: The edge of the flexible cover plate (20) has a notch (202), and the notch (202) is located in the extension direction of the second foldable area (201); The flexible circuit board (30) comprises two first parts (301), and in the extension direction of the first side edge (104), the two first parts (301) are respectively located on two sides of the first foldable area (101); On the first surface (102), the orthographic projections of the two first portions (301) at least partially overlap with the orthographic projections of portions of the flexible cover plate (20) located on both sides of the notch (202).

3. The foldable display device according to claim 2, characterized in that: The width of the notch (202) is greater than or equal to the width of the second foldable area (201), and the width of the notch (202) and the width of the second foldable area (201) are both dimensions in the extension direction of the first side edge (104).

4. The foldable display device according to claim 1, characterized in that: The orthographic projection of the flexible circuit board (30) on the first surface (102) does not overlap with the orthographic projection of the flexible cover plate (20) on the first surface (102).

5. The foldable display device according to any one of claims 1 to 4, characterized in that: A surface (206) of the flexible cover plate (20) away from the flexible display panel (10) is flush with a surface (411) of the annular baffle plate (401) away from the flexible display panel (10).

6. The foldable display device according to any one of claims 1 to 4, characterized in that: The inner edge of the annular baffle (401) is in contact with the edge of the flexible cover plate (20).

7. The foldable display device according to any one of claims 1 to 4, characterized in that: The foldable display device further includes: A first adhesive layer (50) is located between the flexible display panel (10) and the flexible cover plate (20); an orthographic projection of the first adhesive layer (50) on the first surface (102) does not overlap with an orthographic projection of the flexible circuit board (30) on the first surface (102); an edge of the first adhesive layer (50) protrudes from an edge of the flexible cover plate (20) on the side where the first side edge (104) is located; the first adhesive layer (50) and the flexible cover plate (20) form a first step (203); and the annular baffle (401) has a second step (403) that matches the first step (203).

8. The foldable display device according to claim 7, characterized in that: The width of the step surface (231) of the first step (203) ranges from 0.2 millimeters to 0.5 millimeters, and the width of the step surface (231) is the dimension in a direction perpendicular to the extension direction of the first side edge (104) and parallel to the first surface (102).

9. The foldable display device according to any one of claims 1 to 4, characterized in that: The housing (40) further comprises: A bottom plate (404) opposite to the annular baffle (401); The side plate (405) is connected between the outer edge of the bottom plate (404) and the outer edge of the annular baffle (401); the annular baffle (401), the bottom plate (404) and the side plate (405) form a containing space (406); and the flexible display panel (10) is located in the containing space (406).

10. The foldable display device according to any one of claims 1 to 4, characterized in that: The foldable display device further includes: A touch panel (60) located between the flexible display panel (10) and the flexible cover plate (20), the touch panel (60) having a third foldable area (601) and a second side edge (603), the third foldable area (601) including a second sub-area (602), a portion of the second side edge (603) being a boundary of the second sub-area (602); an orthographic projection of the second foldable area (201) on the first surface (102) is located inside an orthographic projection of the third foldable area (601) on the first surface (102), and an orthographic projection of the second foldable area (201) on the first surface (102) does not overlap with an orthographic projection of the second sub-area (602) on the first surface (102); The touch-sensitive flexible circuit board (70) is bound to the second side edge (603), and the orthographic projection of the touch-sensitive flexible circuit board (70) on the first surface (102) does not overlap with the orthographic projection of the third foldable area (601) on the first surface (102).

11. The foldable display device according to claim 10, characterized in that: Two opposite surfaces of the touch panel (60) are bound to the touch flexible circuit board (70).

12. The foldable display device according to claim 11, characterized in that: The foldable display device further includes: The second adhesive layer (80) is located between the touch panel (60) and the flexible display panel (10); the orthographic projection of the second adhesive layer (80) on the first surface (102) does not overlap with the orthographic projection of the touch flexible circuit board (70) on the first surface (102); and on the side where the second side edge (603) is located, the edge of the touch panel (60) protrudes beyond the edge of the second adhesive layer (80).

13. The foldable display device according to any one of claims 1 to 4, characterized in that: The flexible display panel (10) further comprises a second surface (105), the second surface (105) and the first surface (102) being two opposite surfaces of the flexible display panel (10), and the foldable display device further comprises: The support plate (90) has a third surface (901) and a fourth surface (902) opposite to each other, the third surface (901) being in contact with the second surface (105), and the flexible circuit board (30) being bent to the fourth surface (902) of the support plate (90).

14. The foldable display device according to claim 13, characterized in that: The support plate (90) has a groove (903), and the groove (903) extends from the edge of the fourth surface (902) to the middle of the fourth surface (902); The foldable display device further includes: A driving circuit is located in the groove (903), and the flexible circuit board (30) is electrically connected to the driving circuit.

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