Foldable display module and foldable display device

Abstract

An embodiment of the present invention discloses a foldable display module and a foldable display device, the foldable display module including a display panel and a support plate, the support plate including a first group of perforations and a second group of perforations arranged alternately in a second direction, the first group of perforations having a plurality of first vias, the second group of perforations having a plurality of second vias, in the first direction, a length of the first vias is greater than a length of the second vias, and the second vias are arranged to align with first gap portions between adjacent first vias.

Description

Technical Field

[0001] This application relates to the field of displays, and more particularly to a foldable display module and a foldable display device.

Background Art

[0002] In recent years, foldable display modules have become popular among consumers. However, when a foldable screen display module is used for a long time, obvious creases are likely to form in the folding area, resulting in obvious unevenness in the screen-off or display state. Due to the crease problem, it has affected the market expansion of foldable screen display modules.

[0003] Therefore, there is an urgent need for a foldable display module and a foldable display device to solve the above technical problems.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present invention provides a foldable display module and a foldable display device that can alleviate the technical problem of creases in the folding area of the current foldable screen display module.

Means for Solving the Problems

[0005] To solve the above problems, this application provides the following technical solutions.

[0006] The present invention provides a foldable display module, including at least one folding area and a non-folding area adjacent to the folding area. The folding area is adjacent between two non-folding areas and includes a first folding center line. The first folding center line is parallel to a first direction. The foldable display module a display panel, and a support plate provided on one side of the display panel. Here, the support plate includes a plurality of first perforation groups and a plurality of second perforation groups, the extending direction of each first perforation group and each second perforation group is all parallel to the first direction, one first perforation group and one second perforation group are alternately provided in the second direction, the second direction is set to form a predetermined angle with respect to the first direction, the first perforation group has a plurality of first vias provided at intervals along the first direction, the second perforation group has a plurality of second vias provided at intervals along the first direction, the length of the first via in the first direction is greater than the length of the second via in the first direction. The first group of perforations further includes a first gap between two adjacent first vias, and in the second direction, the second via is provided in alignment with the first gap.

[0007] In some embodiments, a plurality of first vias within the first perforation group include two first class vias located at both ends of the first perforation group, and at least one second class via located between the two first class vias, wherein the first class vias include a first portion adjacent to the corresponding end of the first perforation group and a second portion located away from the corresponding end of the first perforation group, and the second class vias include two third portions and a fourth portion located between the two third portions, wherein the third and fourth portions are located along the first direction, where in the second direction, the maximum width of the first portion is less than the minimum width of the second portion, and the minimum width of the third portion is greater than the maximum width of the fourth portion.

[0008] In some embodiments, in the same first type of hole, the ratio of the maximum width of the second portion to the minimum width of the first portion in the second direction is 1.5 to 2. In the same second type of hole, the ratio of the maximum width of the third portion to the minimum width of the fourth portion in the second direction is between 1.5 and 2.

[0009] In some embodiments, the second via includes a fifth portion corresponding to the first gap and a sixth portion located at both ends of the fifth portion, wherein the fifth and sixth portions are provided along the first direction, and in the second direction, the minimum width of the fifth portion is greater than the maximum width of the sixth portion.

[0010] In some embodiments, in the first direction, the length of the sixth portion is less than the length of the corresponding second portion and less than the length of the corresponding third portion.

[0011] In some embodiments, the ends of the second portion, the ends of the third portion, and the ends of the sixth portion have an arc-shaped outer contour; the joint between the first portion and the second portion has an arc-shaped outer contour; the joint between the third portion and the fourth portion has an arc-shaped outer contour; and the joint between the fifth portion and the sixth portion has an arc-shaped outer contour.

[0012] In some embodiments, in at least one of the second perforation groups, the width in the second direction of the fifth portion of the second via that is close to the center of the second perforation group is greater than the width in the second direction of the fifth portion of the second via that is farther from the center of the second perforation group, and in at least one of the second perforation groups, the length in the first direction of the sixth portion of the second via that is close to the center of the second perforation group is greater than the length in the first direction of the sixth portion of the second via that is farther from the center of the second perforation group.

[0013] In some embodiments, in the same second via, the ratio of the length of the second via to the length of the fifth portion in the first direction is 12 to 15.

[0014] In some embodiments, in the same second via, the ratio of the maximum width of the fifth portion to the minimum width of the sixth portion in the second direction is 1.5 to 2.

[0015] In some embodiments, in at least one of the first groups of holes, the length in the first direction of the third portion of the second type of hole that is close to the center of the first group of holes is greater than the length in the first direction of the third portion of the second type of hole that is further away from the center of the first group of holes.

[0016] In some embodiments, in the same second type of hole, the ratio of the length of the second type of hole to the length of the fourth part in the first direction is 1.5 to 2.5.

[0017] In some embodiments, the bending region includes a first sub-bending region, a first sub-planar region on the outer periphery of the first sub-bending region, and a second sub-bending region on the outer periphery of the first sub-planar region, wherein the second sub-bending region is tangent to the non-bending region, the first bending centerline is located within the first sub-bending region, and each of the first and second perforation groups is located within the first sub-bending region, wherein the support plate further includes a plurality of third perforation groups provided within the second sub-bending region, the extending direction of each of the third perforation groups is all parallel to the first direction, and the perforation depth of the third perforation group is less than the thickness of the support plate.

[0018] In some embodiments, the bending region further includes a second bending centerline, the second bending centerline being parallel to the first direction and located within the second sub-bending region, where the depth of the third group of perforations in the direction adjacent to the second bending centerline is greater than the depth of the third group of perforations in the direction away from the second bending centerline.

[0019] In some embodiments, the distance between two adjacent groups of the third perforation groups gradually decreases in the direction approaching the second bending center line.

[0020] In some embodiments, the display panel includes a panel body, a polarizing layer located close to the light-emitting side of the panel body, a window cover on the side of the polarizing layer away from the panel body, and a back plate located away from the light-emitting side of the panel body. Here, the support plate is positioned away from the Idemitsu side of the panel body.

[0021] The present invention further provides a foldable display device, comprising a foldable display module, the foldable display module comprising at least one foldable region and a non-foldable region adjacent to the foldable region, the foldable region adjacent to the two non-foldable regions and comprising a first fold center line, the first fold center line being parallel to a first direction, and the foldable display module, Display panel and, The display panel includes a support plate provided on one side of the display panel, Here, the support plate includes a plurality of first perforation groups and a plurality of second perforation groups, the extending direction of each first perforation group and each second perforation group is all parallel to the first direction, one first perforation group and one second perforation group are alternately provided in the second direction, the second direction is set to form a predetermined angle with respect to the first direction, the first perforation group has a plurality of first vias provided at intervals along the first direction, the second perforation group has a plurality of second vias provided at intervals along the first direction, the length of the first via in the first direction is greater than the length of the second via in the first direction. The first group of perforations further includes a first gap between two adjacent first vias, and in the second direction, the second via is provided in alignment with the first gap.

[0022] In some embodiments, the plurality of first vias within the first perforation group include two first type holes provided at both ends of the first perforation group, and at least one second type hole provided between the two first type holes. The first type of holes includes a first portion close to the corresponding end of the first perforation group and a second portion away from the corresponding end of the first perforation group. The second type of holes includes two third portions and a fourth portion provided between the two third portions. The third portion and the fourth portion are provided along the first direction. Here, in the second direction, the maximum width of the first portion is smaller than the minimum width of the second portion, and the minimum width of the third portion is larger than the maximum width of the fourth portion.

[0023] In some embodiments, the second via includes a fifth portion corresponding to the first gap portion and a sixth portion located at both ends of the fifth portion. Here, the fifth portion and the sixth portion are provided along the first direction. In the second direction, the minimum width of the fifth portion is larger than the maximum width of the sixth portion.

[0024] In some embodiments, in at least one of the first perforation groups, the length in the first direction of the third portion of the second type of holes close to the center of the first perforation group is larger than the length in the first direction of the third portion of the second type of holes away from the center of the first perforation group.

[0025] In some embodiments, the bending region includes a first sub-bending region, a first sub-planar region on the outer periphery of the first sub-bending region, and a second sub-bending region on the outer periphery of the first sub-planar region. The second sub-bending region is in contact with the non-bending region. The first bending center line is located within the first sub-bending region, and each of the first perforation groups and each of the second perforation groups are located within the first sub-bending region. Here, the support plate further includes a plurality of third perforation groups provided within the second sub-bending region. The extending directions of all the third perforation groups are parallel to the first direction, and the opening depth of the third perforation groups is smaller than the thickness of the support plate.

Advantages of the Invention

[0026] The present invention has the following beneficial effects. Specifically, in the present invention, vias of different lengths are provided in the bending region, with long via groups and short via groups alternately provided, and a second via is provided aligned with the first gap. This further reduces the bending stress in the first gap with the short vias, releasing the bending stress more uniformly. Furthermore, the short vias reduce the amount of support plate material removed, improving the support performance of the support plate. The alternating long / short vias increase the complexity of the via arrangement, diversifying the stress release paths. As a result, the torsional stress and support rigidity of the support plate are balanced, the bending stress is released more uniformly, and in the folded state, the bending arc shape portion having a teardrop-shaped fold of the foldable display module is closer to a circular shape, further reducing and making the applied force more uniform, thereby mitigating the folds of the foldable display module. [Brief explanation of the drawing]

[0027] [Figure 1] This is a schematic diagram of one structure of a foldable display module provided in an embodiment of the present invention. [Figure 2] This is a schematic diagram of one structural support plate for a foldable display module provided in an embodiment of the present invention. [Figure 3] This is a magnified view of area A in Figure 2. [Figure 4] This is a magnified view of area B in Figure 3. [Figure 5] This is a partially enlarged view of a second type of hole in a foldable display module provided in an embodiment of the present invention. [Figure 6] This is a partial enlarged view of the second via of a foldable display module provided in an embodiment of the present invention. [Figure 7] This is another schematic diagram of the support plate for a foldable display module provided in an embodiment of the present invention. [Figure 8] Figure 7 is a schematic diagram of the structure along the C1-C2 section. [Figure 9] This is another schematic diagram of the structure of a foldable display module provided in an embodiment of the present invention. [Figure 10]This is a schematic simulation of a foldable display module provided in an embodiment of the present invention. [Figure 11] This is a comparative schematic diagram of the folding simulation of a foldable display module provided in an embodiment of the present invention. [Figure 12] This is a comparative experimental characterization diagram of a foldable display module provided in an embodiment of the present invention. [Figure 13] This is a schematic diagram of the structure of a foldable display device provided in an embodiment of the present invention. [Figure 14] This is a schematic diagram of the exploded structure of a foldable display device provided in an embodiment of the present invention. [Modes for carrying out the invention]

[0028] This application provides a foldable display module and a foldable display device. To make the purpose, technical solution, and effects of this application clearer and more evident, the application will be described in more detail below with reference to the drawings, including examples. It should be understood that the specific examples described herein are for interpretation purposes only and are not intended to limit the application.

[0029] Embodiments of the present application provide a foldable display module and a foldable display device. Each will be described in detail below. It should be noted that the order of description of the embodiments below is not limited to a preferred order.

[0030] In recent years, foldable display modules have become popular with consumers. However, with prolonged use, foldable screen display modules tend to develop noticeable creases within the folded area. As a result, a noticeable unevenness occurs when the screen is off or when it is displayed. This crease problem is affecting the market development of foldable screen display modules.

[0031] Referring to Figures 1 to 12, an embodiment of the present invention provides a foldable display module 100 comprising at least one foldable region 110 and a non-foldable region 120 adjacent to the foldable region 110, wherein the foldable region 110 is adjacent to two of the non-foldable regions 120, the foldable region 110 includes a first fold center line 101, the first fold center line 101 is parallel to a first direction, and the foldable display module 100 is, Display panel 200 and, The display panel 200 includes a support plate 300 provided on one side, Here, the support plate 300 includes a plurality of first perforation groups 400 and a plurality of second perforation groups 500, the extending direction of each first perforation group 400 and each second perforation group 500 is all parallel to the first direction, one first perforation group 400 and one second perforation group 500 are alternately provided in the second direction, the second direction is set to form a predetermined angle with respect to the first direction, the first perforation group 400 has a plurality of first vias 410 provided at intervals along the first direction, the second perforation group 500 has a plurality of second vias 510 provided at intervals along the first direction, the length of the first vias 410 in the first direction is greater than the length of the second vias 510 in the first direction. The first group of perforations 400 further includes a first gap 420 between two adjacent first vias 410, and in the second direction, the second via 510 is provided in alignment with the first gap 420.

[0032] In this invention, vias of different lengths are provided in the bending region, with long via groups and short via groups arranged alternately, and a second via is provided aligned with the first gap. This further reduces the bending stress in the first gap with the short vias, resulting in a more uniform release of the bending stress. Additionally, the short vias reduce the amount of support plate material removed, improving the support performance of the support plate. The alternating long and short vias increase the complexity of the via arrangement, diversifying the stress release paths. As a result, the torsional stress and support rigidity of the support plate are balanced, the bending stress is released more uniformly, and in the folded state, the bending arc shape of the teardrop-shaped folded form of the foldable display module becomes closer to a circular shape, further reducing and making the applied force more uniform, thereby mitigating the folds of the foldable display module.

[0033] Now, we will explain the technical solutions of the present invention in combination with specific examples.

[0034] In this embodiment, referring to Figures 1 to 4 and 9, the foldable display module 100 includes at least one foldable region 110 and a non-foldable region 120 adjacent to the foldable region 110, the foldable region 110 adjacent to two of the non-foldable regions 120, the foldable region 110 includes a first fold centerline 101, the first fold centerline 101 is parallel to a first direction.

[0035] The foldable display module 100 includes a display panel 200 and a support plate 300 provided on one side of the display panel 200, the support plate 300 including a plurality of first perforation groups 400 and a plurality of second perforation groups 500, the extending directions of each of the first perforation groups 400 and each of the second perforation groups 500 are all parallel to the first direction, one of the first perforation groups 400 and one of the second perforation groups 500 are alternately provided in the second direction, the second direction is set to form a preset angle with the first direction, the first perforation group 400 has a plurality of first vias 410 provided at intervals along the first direction, and the second perforation group 500 has a plurality of second vias 510 provided at intervals along the first direction, the length of the first vias 410 in the first direction is greater than the length of the second vias 510 in the first direction. The first group of perforations 400 further includes a first gap 420 between two adjacent first vias 410, and in the second direction, the second via 510 is provided in alignment with the first gap 420.

[0036] Let us explain using the example of the first direction being the X-axis and the second direction being the Y-axis. The first perforation group 400 includes a plurality of first vias 410 provided and extending in the X-axis direction, and in the first perforation group 400, there is a first gap 420 between two adjacent first vias, and the first gap 420 is the solid material of the support plate 300, i.e., a non-perforated portion, and during folding, the torsional stress for folding is mainly concentrated in the first gap 420, and the torsional stress still cannot be effectively released, so a second perforation group 500 is provided between two adjacent first perforation groups 400 in the second direction, and the second perforation group 500 includes a plurality of second vias 510 provided and extending in the X-axis direction, and in the Y-axis direction, the second vias 510 are provided in alignment with the first gap 420.

[0037] If vias within the first group of perforations 400 are provided only within the first gap 420, the arrangement of holes becomes excessively simple, the stress release path becomes simple, and it becomes impossible to release complex torsional stresses from each direction. By providing the second via 510 in the vicinity of the first via 410 and corresponding to the first gap, the complexity of the via arrangement is increased, the stress release path is more diverse, which helps to release complex torsional stresses during folding, the bending stress is released more uniformly, and in the folded state, the bending arc shape portion having a teardrop-shaped folding form of the foldable display module 100 becomes closer to a circular shape, further reducing and making the applied force more uniform, thereby easing the folds of the foldable display module 100.

[0038] In some embodiments, referring to Figures 3 to 6, the plurality of first vias 410 within the first perforation group 400 include two first type holes 431 provided at both ends of the first perforation group 400, and at least one second type hole 432 provided between the two first type holes 431, wherein the first type hole 431 includes a first portion 610 adjacent to the corresponding end of the first perforation group 400, and a second portion 620 away from the corresponding end of the first perforation group 400, and the second type hole 432 includes two third portions 630, and a fourth portion 640 provided between the two third portions 630, wherein the third portions 630 and the fourth portion 640 are provided along the first direction, where in the second direction, the maximum width of the first portion 610 is less than the minimum width of the second portion 620, and the minimum width of the third portion 630 is greater than the maximum width of the fourth portion 640.

[0039] The first portion 610 and the fourth portion 640 have reduced width to improve the support molding performance of the support material around the first portion 610 and the fourth portion 640, ensuring that the support plate 300 does not easily deform and collapse during folding, while the third portion 630 and the second portion 620 have increased width to reduce torsional stress during folding, thus balancing uniform torsional stress and support rigidity, further improving the complexity of the vias, allowing the perforated contour of the material of the support plate 300 to cover more stress release directions, allowing bending stress to be released in more directions, increasing the release paths for bending stress, which helps in the uniform release of bending stress, and in the folded state, the bending arc-shaped portion having a teardrop-shaped fold of the foldable display module 100 is closer to a circular shape, further reducing and making the forces received more uniform, thereby easing the folds of the foldable display module 100.

[0040] In some embodiments, referring to Figures 3 to 6, the second via 510 includes a fifth portion 650 corresponding to the first gap 420, and a sixth portion 660 located at both ends of the fifth portion 650, wherein the fifth portion 650 and the sixth portion 660 are provided along the first direction, and in the second direction, the minimum width of the fifth portion 650 is greater than the maximum width of the sixth portion 660.

[0041] By increasing the width of the fifth portion 650 corresponding to the first gap 420, the amount of support material around the first gap 420 is reduced, reducing torsional stress during folding, the path of the support material acts as a carrier for stress release, the complexity of the contour of the support material between the fifth portion 650 and the second portion 620 and the third portion 630 is improved, the perforated contour of the material of the support plate 300 can cover more stress release directions, bending stress can be released in more directions, the diversity of stress release paths is improved, bending stress is released more uniformly, and in the folded state, the folded arc shape portion having a teardrop-shaped folded form of the foldable display module 100 is closer to a circular form, further reducing and making the applied force more uniform, thereby easing the fold of the foldable display module 100.

[0042] In some examples, an experimental group and a comparison group were established, and folding experiments were conducted under different experimental conditions for the support plate 300, with the thickness of the support plate 300 in both the comparison group and the experimental group set to 0.2 mm.

[0043] In the comparison group, the condition is that the support plate 300 is an array type with uniformly opened holes, while in the experimental group, the condition is that in the second direction, the maximum width of the first portion 610 is smaller than the minimum width of the second portion 620, the minimum width of the third portion 630 is larger than the maximum width of the fourth portion 640, and in the second direction, the minimum width of the fifth portion 650 is larger than the maximum width of the sixth portion 660.

[0044] Referring to Figures 9 to 12, a simulation diagram of the final folded form of the foldable display module 100 is created, and stress measurements are performed. In the stress comparison diagram 12, the horizontal coordinate represents the path distance from the measurement point to the first bending center line 101, in millimeters, and the vertical coordinate represents the magnitude of the stress, in megapascals.

[0045] As can be seen from the comparison, the morphological design of the perforation structure of the present invention allows for the optimization of the droplet shape. That is, after folding the module, the first sub-folding region 111 of the droplet-shaped folding arc region can be brought closer to a circular shape from an elliptical shape, thereby reducing the intermediate curvature of the droplet, increasing the radius, and improving the force acting on the module.

[0046] In the comparison group, the curvature of the central bending region 110 is small, resulting in a large overall force, and it is not possible to adjust the teardrop-shaped bending form of the screen body. In the experimental group, the teardrop shape can be adjusted to increase the curvature of the central bending region 110. As a result, the first sub-bending region 111 of the teardrop-shaped bending arc region is closer to a circular arc shape and can play a role in distributing stress. Therefore, the force received by the window cover 230, which is a film layer in the module, is clearly reduced, which helps to reduce the number of folds.

[0047] In some embodiments, referring to Figures 4 and 6, in the first direction, the length of the sixth portion 660 is less than the length of the corresponding second portion 620 and less than the length of the corresponding third portion 630.

[0048] The main roles of the first portion 610 and the fourth portion 640 are to provide the support plate 300 with high rigidity and to ensure that the support plate 300 does not easily deform and collapse during folding, and the main roles of the second portion 620 and the third portion 630 are to reduce torsional stress and improve stress release uniformity. Therefore, the sixth portion 660 does not extend into the first portion 610 or the fourth portion 640, that is, in the second direction, the second via 510 is not provided between two adjacent first portions 610 and between two adjacent fourth portions 640. This reduces the through-hole ratio of the folding region 110, provides the folding region 110 with higher support, ensures the rigidity of the support plate 300, prevents the support plate 300 from deforming and collapsing during folding, and mitigates the folds of the foldable display module 100.

[0049] In some embodiments, referring to Figures 4 to 6, the ends of the second portion 620, the end of the third portion 630, and the end of the sixth portion 660 have an arc-shaped outer contour; the joint between the first portion 610 and the second portion 620 has an arc-shaped outer contour; the joint between the third portion 630 and the fourth portion 640 has an arc-shaped outer contour; and the joint between the fifth portion 650 and the sixth portion 660 has an arc-shaped outer contour.

[0050] The arc shape helps in the uniform release of stress, and, under the condition that the perimeter is the same, the area of ​​the arc shape is larger than the area of ​​the linear pattern, thereby increasing the drilling area, further reducing torsional stress, lowering the risk of stress concentration, and improving the uniformity of stress release. The arc shape may be circular or elliptical, and this is merely an example and not a specific limitation.

[0051] In some embodiments, referring to Figures 4 to 6, the joint between the first part 610 and the second part 620 has an arc-shaped outer contour, the joint between the third part 630 and the fourth part 640 has an arc-shaped outer contour, and the joint between the fifth part 650 and the sixth part 660 has an arc-shaped outer contour. The area of ​​the arc shape is larger than the area of ​​the linear pattern, thereby increasing the area of ​​the drilling, further reducing torsional stress, reducing the risk of stress concentration, and improving the uniformity of stress release. The arc shape may be one, two or more combinations of circles, ellipses, quadratic curves, and parabolas, and is not specifically limited here. For example, the arc shape may consist of two elliptical arcs r1 and r2.

[0052] In some embodiments, in the same first type of hole 431, the ratio of the maximum width of the second portion 620 to the minimum width of the first portion 610 in the second direction is 1.5 to 2. If the value of this ratio is too large or too small, the balance between stress relief performance and support stiffness is not maintained, affecting the performance parameters of the support plate 300 and causing noticeable creases.

[0053] In some embodiments, in the same second type of hole 432, the ratio of the maximum width of the third portion 630 to the minimum width of the fourth portion 640 in the second direction is 1.5 to 2. If the ratio is too large or too small, the balance between stress relief performance and support stiffness is not maintained, affecting the performance parameters of the support plate 300 and causing noticeable creases.

[0054] In some embodiments, in the same second via 510, the ratio of the maximum width of the fifth portion 650 to the minimum width of the sixth portion 660 in the second direction is 1.5 to 2. If the ratio is too large or too small, the balance between stress relief performance and support stiffness is not maintained, affecting the performance parameters of the support plate 300 and causing noticeable creases.

[0055] In some embodiments, referring to Figure 5, in the second direction, the width of the first portion 610 is 0.1 mm to 0.15 mm, and the width a3 of the fourth portion 640 is 0.1 mm to 0.15 mm. Being within this numerical range allows for effective stress relief and also provides high support rigidity. The width of the first portion 610 is similar to that of the fourth portion 640, thus avoiding the need for repeated diagrams.

[0056] In some embodiments, the ratio of the length of the second via 432 to the length of the second via 510 in the first direction is between 2 and 5. If the ratio is too large or too small, the balance between stress relief performance and support stiffness is not maintained, affecting the performance parameters of the support plate 300 and causing noticeable creases.

[0057] In some embodiments, referring to Figures 5 and 6, the ends of the second portion 620, the third portion 630, and the sixth portion 660 have a semi-elliptical outer contour, where the ratio of the major axis a2 to the minor axis a1 of the semi-ellipse is 2 to 3. If the ratio is too large or too small, the balance between stress relief performance and support stiffness will be disrupted, affecting the performance parameters of the support plate 300 and causing noticeable creases.

[0058] In some embodiments, referring to Figure 5, in the same second type hole 432, the ratio of the length L1 of the second type hole 432 to the length L2 of the fourth part 640 in the first direction is 1.5 to 2.5.

[0059] The ratio of the lengths of the two parts of the second type hole 432 must be limited to some extent according to the following limiting rules.

[0060] The relationship between the length of the holes and the stress is a design parameter related to the material of the support plate 300. Generally, the material of the support plate 300 is SUS stainless steel, which has a yield strength of about 1600 MPa and a fatigue strength of about 0.5 times the yield strength of the material. Therefore, during design, a fatigue strength of 800 MPa is used as the design standard stress, and the ratio of the lengths is determined by simulation. The relationship between the ratio of L1 to L2 and the stress is shown in Table 1, which is a simulation comparison table.

[0061] [Table 1]

[0062] The relationship between hole length and support capacity is addressed by checking the ratio of hole lengths and the simulated repulsive force after bending. The repulsive force can reflect support capacity to some extent and is determined by considering two factors: fatigue stress strength and the elastic force of the closed module. Theoretically, the greater the repulsive force, the higher the support capacity, the more difficult it is to bend, and the greater the stress. However, if the repulsive force is too great, it becomes difficult to close the screen after folding. For this reason, it is necessary to add magnets to the intermediate frame of the foldable display device for adhesion. The size of the magnetic material is directly related to the repulsive force, and generally, the limiting force of the magnetic material is about 4N. Therefore, 4N is used as the design standard repulsive force during the design phase, and the ratio of lengths is determined by simulation, as shown in Table 2, which is a simulation comparison table between the ratio of L1 and L2 and the repulsive force.

[0063] [Table 2]

[0064] If the L1 / L2 ratio is too large or too small, the balance between stress release performance and support stiffness will be disrupted, affecting the performance parameters of the support plate 300 and causing noticeable creases. Therefore, to balance the support stiffness and bendability of the support plate 300 and to meet the product shipping standards, the L1 / L2 ratio is set to 1.5 to 2.5.

[0065] In some embodiments, referring to Figure 6, in the same second via 510, the ratio of the length L4 of the second via 510 to the length L3 of the fifth portion 650 in the first direction is 12 to 15.

[0066] Similarly, the ratio of the lengths of the two parts of the second via 510 must also be restricted to some extent; refer to the limiting rules for the L1 / L2 ratio for the restriction rules. See Table 3 for the simulation results between the L4 / L3 ratio and stress, and Table 4 for the simulation results between the L4 / L3 ratio and repulsive force.

[0067] [Table 3]

[0068] [Table 4]

[0069] If the L4 / L3 ratio is too large or too small, the balance between stress release performance and support stiffness will be disrupted, affecting the performance parameters of the support plate 300 and causing obvious creases. Therefore, to balance the support stiffness and bendability of the support plate 300 and to meet the product shipping standards, the L4 / L3 ratio should be set to 12 to 15 depending on the trend.

[0070] The percentages shown in the diagram are approximate; please refer to the specific data above for detailed percentages.

[0071] In some embodiments, in the first direction, the ratio of the length of the first type hole 431 to the length of the second type hole 432 is between 1 / 2 and 2 / 3.

[0072] In some embodiments, referring to Figures 9 and 11, experiments are conducted using the average values ​​of the above ratio parameters as experimental values. By optimizing the combination relationships of the above structural features and dimensions, and by combining this with a mechanical simulation mode, the above dimensional parameters are adjusted, and each dimension is brought within the range described above, thereby controlling the teardrop-shaped folding form of the folding screen under the folded state, making the intermediate folding arc portion R1 of the first sub-folding region 111 of the folding region 110 circular, thereby reducing or making the applied force more uniform, reducing the magnitude of the force and strain applied to the folded part of the module overall, and easing the crease.

[0073] In some embodiments, in at least one of the second perforation groups 500, the width in the second direction of the fifth portion 650 of the second via 510 that is close to the center of the second perforation group 500 is greater than the width in the second direction of the fifth portion 650 of the second via 510 that is farther from the center of the second perforation group 500, and in at least one of the second perforation groups 500, the length in the first direction of the sixth portion 660 of the second via 510 that is close to the center of the second perforation group 500 is greater than the length in the first direction of the sixth portion 660 of the second via 510 that is farther from the center of the second perforation group 500.

[0074] In the direction from the end of the second perforation group 500 to the center of the second perforation group 500, the cross-change of bending stress becomes more complex the further away from the end of the second perforation group 500, thus improving the perforation rate of the second perforation group 500, reducing the material of the support plate 300 between the fifth portion 650 and the third portion 630, improving the bending performance of the support plate 300, and increasing the complexity of the contour of the support plate between the fifth portion 650 and the third portion 630, allowing the perforation contour of the material of the support plate 300 to cover more stress release directions, allowing bending stress to be released in more directions, improving the diversity of stress release paths, and releasing bending stress more uniformly. In the folded state, the bending arc shape portion having a teardrop-shaped fold of the foldable display module 100 is closer to a circular shape, further reducing and making the applied force more uniform, thereby easing the fold of the foldable display module 100.

[0075] In some embodiments, in at least one of the first group of holes 400, the length in the first direction of the third portion 630 of the second type of hole 432 that is close to the center of the first group of holes 400 is greater than the length in the first direction of the third portion 630 of the second type of hole 432 that is further away from the center of the first group of holes 400.

[0076] In the direction from the end of the first perforation group 400 to the center of the first perforation group 400, the third portion 630 becomes longer and the fourth portion 640 becomes shorter as it approaches the center of the first perforation group 400, the perforation rate of the first perforation group 400 increases, the bending performance of the support plate 300 increases, more bending stress is released and the folds of the foldable display module 100 can be eased.

[0077] In some embodiments, referring to Figures 2, 8, and 9, the bent region 110 includes a first sub-bent region 111, a first sub-planar region 112 on the outer periphery of the first sub-bent region 111, and a second sub-bent region 113 on the outer periphery of the first sub-planar region 112, wherein the second sub-bent region 113 is in contact with the non-bent region 120, the first bend centerline 101 is located within the first sub-bent region 111, and the first perforation group 400 and each of the second perforation groups 500 are located within the first sub-bent region 111. Here, the support plate 300 further includes a plurality of third perforation groups 700 provided within the second sub-bent region 113, the extending direction of each of the third perforation groups 700 is all parallel to the first direction, and the perforation depth of the third perforation group 700 is less than the thickness of the support plate 300.

[0078] When the foldable display module 100 is in the folded state, the bending region 110 takes on a teardrop shape and, in order to assist in folding and release folding stress, has an arc-shaped portion R1 at the bottom of the teardrop shape corresponding to the first sub-bending region 111, as well as an arc-shaped portion R2 at the top of the teardrop shape corresponding to the second sub-bending region 113. However, since the bending arc within the second sub-bending region 113 is small and there is no need to provide vias, the third group of perforations 700 becomes a semi-etched hole in order to provide enhanced bending performance and to maintain more rigid support performance.

[0079] In some embodiments, referring to Figure 9, the bending region 110 further includes a second bending center line 102, which is parallel to the first direction and located within the second sub-bending region 113, where the depth of the third perforation group 700 gradually increases in the direction approaching the second bending center line 102.

[0080] The closer to the second bending center line 102, the larger the bending radius and the greater the depth of the third perforation group 700. This allows for higher bending performance, releases more bending stress, and reduces the creases in the foldable display module 100.

[0081] In some embodiments, the distance between two adjacent groups of the third perforation groups 700 gradually decreases in the direction approaching the second bending center line 102.

[0082] The closer to the second bending center line 102, the larger the bending radius becomes, the higher the installation density of the third perforation group 700, and the higher the perforation rate. Therefore, higher bending performance can be provided, more bending stress can be released, and the folds of the foldable display module 100 can be alleviated.

[0083] In some embodiments, the ratio of the drilling depth of the third group of holes 700 to the thickness of the support plate 300 is between 1 / 2 and 2 / 3. If this ratio is too large or too small, it will affect the balance between bending performance and support performance, affecting the performance parameters of the support plate 300 and resulting in noticeable creases.

[0084] In some embodiments, the ratio of the perforation width of the third perforation group 700 to the distance between two adjacent perforation groups is between 1 and 5. If this ratio is too large or too small, it will affect the balance between bending performance and support performance, affecting the performance parameters of the support plate 300 and resulting in noticeable creases.

[0085] In some embodiments, the drilling width of the third drilling group 700 is 0.25 mm to 0.5 mm. Within this range, stress can be effectively released and high support rigidity can also be provided.

[0086] In some embodiments, referring to Figures 8 and 9, the display panel 200 includes a panel body 210, a polarizing layer 220 located close to the light-emitting side of the panel body 210, a window cover 230 on the side of the polarizing layer 220 away from the panel body 210, and a back plate 240 located away from the light-emitting side of the panel body 210. Here, for ease of diagram production, in Figure 9, the polarizing layer 220 and the window cover 230 are represented as a composite layer 250.

[0087] In some embodiments, referring to Figures 8 and 9, the support plate 300 is positioned away from the light-emitting side of the panel body 210.

[0088] In some embodiments, the material of the support plate 300 is one of steel plate, titanium alloy, carbon fiber, or polymer composite material, and this is merely an example and not specifically limited thereto.

[0089] In some embodiments, the thickness of the support plate 300 is 0.1 mm to 0.2 mm to balance the drilling rate and support performance.

[0090] In this invention, vias of different lengths are provided in the bending region, with long via groups and short via groups alternating, and a second via is provided aligned with the first gap. This further reduces the bending stress in the first gap with the short vias, releasing the bending stress more uniformly. Additionally, the short vias reduce the amount of support plate material removed, improving the support performance of the support plate. As a result, the torsional stress and support rigidity of the support plate are balanced, the bending stress is released more uniformly, and in the folded state, the bending arc shape of the teardrop-shaped folded form of the foldable display module becomes closer to a circular shape, further reducing and making the applied force more uniform, thereby mitigating the crease of the foldable display module.

[0091] Referring to Figures 13 and 14, embodiments of the present invention further provide a foldable display device 10, which includes any one of the above-described foldable display modules 100.

[0092] In some embodiments, the foldable display device 10 further includes a device body 20, and the foldable display module 100 is integrated with the device body 20.

[0093] The specific structure of the aforementioned foldable display module 100 is described by referring to the embodiment and drawings of one of the above-described foldable display module 100s, and is omitted here.

[0094] In this embodiment, the main body of the device 20 may include an intermediate frame, frame adhesive, external mounting elements, hinges, etc., and the foldable display device 10 may be a display terminal such as a mobile phone, tablet, or television, and is not limited thereto.

[0095] In some embodiments, the support plate 300 corresponding to the first subplanar region 112 can be used to connect to the hinge's float structure with an adhesive.

[0096] In some embodiments, the foldable display device 10 further includes a corresponding adhesive layer 30.

[0097] Embodiments of the present invention disclose a foldable display module and a foldable display device. The foldable display module includes a display panel and a support plate, the support plate including a plurality of first perforation groups and a plurality of second perforation groups, one first perforation group and one second perforation group arranged alternately in a second direction, the first perforation group having a plurality of first vias, and the second perforation group having a plurality of second vias, the length of the first vias in the first direction being greater than the length of the second vias in the first direction, and the second vias being provided to fit into a first gap between two adjacent first vias. In the present invention, by providing long / short vias of different lengths arranged alternately in the bending region, the bending stress in the first gap is reduced by the short vias, the removal of support plate material by the short vias is reduced, the support performance of the support plate is improved, the complexity of via arrangement is increased, the stress release paths are more diverse, and thus the torsional stress and support stiffness of the support plate are balanced, and the folded arc shape when folded is closer to a circular shape.

[0098] Those skilled in the art will understand that equivalent substitutions and modifications based on the technical solution and concept of the invention of this application are possible, and that all such modifications and substitutions are included within the scope of protection of the claims attached to this application.

Claims

1. A foldable display module comprising at least one foldable region and a non-foldable region adjacent to the foldable region, wherein the foldable region is adjacent to the two non-foldable regions and includes a first fold center line, the first fold center line is parallel to a first direction, and the foldable display module is, Display panel and, The display panel includes a support plate provided on one side of the display panel, Here, the support plate includes a plurality of first perforation groups and a plurality of second perforation groups, the extending direction of each first perforation group and each second perforation group is all parallel to the first direction, one first perforation group and one second perforation group are alternately provided in the second direction, the second direction is set to form a predetermined angle with respect to the first direction, the first perforation group has a plurality of first vias provided at intervals along the first direction, the second perforation group has a plurality of second vias provided at intervals along the first direction, the length of the first via in the first direction is greater than the length of the second via in the first direction. The first group of perforations further includes a first gap between two adjacent first vias, and in the second direction, the second via is arranged to align adjacent to the two first gaps located on either side of the second via. The folding region includes a first sub-folding region, a first sub-planar region on the outer periphery of the first sub-folding region, and a second sub-folding region on the outer periphery of the first sub-planar region, the second sub-folding region being in contact with the non-folding region, The first folding center line is located within the first sub-folding region, and each of the first perforation groups and each of the second perforation groups are located within the first sub-folding region. Herein, the support plate further includes a plurality of third perforation groups provided within the second sub-bending region, the extending direction of each third perforation group is all parallel to the first direction, and the perforation depth of the third perforation group is less than the thickness of the support plate, a foldable display module.

2. The plurality of first vias within the first perforation group include two first type holes provided at both ends of the first perforation group, and at least one second type hole provided between the two first type holes. The first type of hole includes a first portion adjacent to the corresponding end of the first group of perforations, and a second portion away from the corresponding end of the first group of perforations. The second type of hole includes two third portions and a fourth portion provided between the two third portions, and the third and fourth portions are provided along the first direction. The foldable display module according to claim 1, wherein, in the second direction, the maximum width of the first portion is smaller than the minimum width of the second portion, and the minimum width of the third portion is larger than the maximum width of the fourth portion.

3. In the same first type of hole, the ratio of the maximum width of the second portion to the minimum width of the first portion in the second direction is 1.5 to 2. The foldable display module according to claim 2, wherein in the same second type of hole, the ratio of the maximum width of the third portion to the minimum width of the fourth portion in the second direction is 1.5 to 2.

4. The second via includes a fifth portion corresponding to the first gap and a sixth portion located at both ends of the fifth portion. The foldable display module according to claim 2, wherein the fifth and sixth portions are provided along the first direction, and in the second direction, the minimum width of the fifth portion is greater than the maximum width of the sixth portion.

5. The foldable display module according to claim 4, wherein in the first direction, the length of the sixth portion is less than the length of the corresponding second portion and less than the length of the corresponding third portion.

6. The ends of the second portion, the third portion, and the sixth portion have an arc-shaped outer contour. The foldable display module according to claim 4, wherein the joint between the first and second parts has an arc-shaped outer contour, the joint between the third and fourth parts has an arc-shaped outer contour, and the joint between the fifth and sixth parts has an arc-shaped outer contour.

7. In at least one of the second perforation groups, the width in the second direction of the fifth portion of the second via that is close to the center of the second perforation group is greater than the width in the second direction of the fifth portion of the second via that is further away from the center of the second perforation group. The foldable display module according to claim 4, wherein in at least one of the second perforation groups, the length in the first direction of the sixth portion of the second via adjacent to the center of the second perforation group is greater than the length in the first direction of the sixth portion of the second via far from the center of the second perforation group.

8. The collapsible display module according to claim 4, wherein in the same second via, the ratio of the length of the second via to the length of the fifth portion in the first direction is 12 to 15.

9. The collapsible display module according to claim 4, wherein in the same second via, the ratio of the maximum width of the fifth portion to the minimum width of the sixth portion in the second direction is 1.5 to 2.

10. The foldable display module according to claim 2, wherein in at least one of the first groups of holes, the length in the first direction of the third portion of the second type of hole adjacent to the center of the first group of holes is greater than the length in the first direction of the third portion of the second type of hole away from the center of the first group of holes.

11. The foldable display module according to claim 2, wherein in the same second type of hole, the ratio of the length of the second type of hole to the length of the fourth portion in the first direction is 1.5 to 2.

5.

12. The aforementioned folding region further includes a second folding center line, the second folding center line being parallel to the first direction and located within the second sub-folding region. The foldable display module according to claim 1, wherein the depth of the third group of perforations in the direction adjacent to the second center line of fold is greater than the depth of the third group of perforations in the direction away from the second center line of fold.

13. The foldable display module according to claim 12, wherein the distance between two adjacent groups of the third perforation groups gradually decreases in the direction approaching the second folding center line.

14. The display panel includes a panel body, a polarizing layer located close to the light-emitting side of the panel body, a window cover on the side of the polarizing layer away from the panel body, and a back plate located away from the light-emitting side of the panel body. The foldable display module according to claim 1, wherein the support plate is positioned away from the Idemitsu side of the panel body.

15. A foldable display device comprising a foldable display module according to any one of claims 1 to 14.

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