Display module and display device
By combining a black tape inside the polarizer aperture and a light-shielding adhesive layer on the sidewall of the backlight aperture, the problem of polarizer cracking in the reliability temperature shock test was solved, achieving a thinner and lighter polarizer design and normal camera function.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- BEIJING BOE DISPLAY TECH CO LTD
- Filing Date
- 2025-07-01
- Publication Date
- 2026-06-23
Smart Images
Figure CN224399700U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of display technology, and more particularly to a display module and a display device. Background Technology
[0002] With increasing competition in the electronics industry and rapid technological upgrades, the requirements for thinner and lighter product designs are becoming increasingly stringent. For polarizers, in order to meet these thinner and lighter design requirements, some polarizers may crack during reliability temperature shock tests, leading to product certification failure. Utility Model Content
[0003] This application proposes a display module and display device, aiming to improve the problem of polarizer cracking in reliable temperature shock tests and achieve product thinning.
[0004] To achieve the above objectives, embodiments of this application provide the following technical solutions:
[0005] On one hand, a display module is provided, including a display area and a light-transmitting area located within the display area. The display module further includes a display panel, a first polarizer, black adhesive tape, a backlight, and a light-shielding adhesive layer. The display panel includes opposing display surfaces and non-display surfaces. The first polarizer is disposed on the non-display surface and includes a first via located within the light-transmitting area. The black adhesive tape is disposed on the non-display surface, and its orthographic projection on the display panel is annular and located within the range of the orthographic projection of the first via on the display panel. The backlight is disposed on the side of the first polarizer away from the display panel and includes a second via located within the light-transmitting area. The light-shielding adhesive layer is at least partially disposed on the sidewall of the second via and connected to the black adhesive tape.
[0006] In this application, the first via of the first polarizer is located in the light-transmitting area, which can avoid the influence of the polarization effect of the polarizer on the light. The annular black tape is set within the orthographic projection range of the first via. The black tape does not overlap with the first polarizer. The two are two independent entities. In the reliability temperature shock test, the two expand and contract independently, and have almost no influence on each other. There will be no problem of the black tape tearing the first polarizer, thus avoiding cracks in the first polarizer.
[0007] Furthermore, the black tape, positioned within the orthographic projection area of the first via, can also shield the sidewall of the first polarizer at the first via, preventing light leakage from the first polarizer into the light-transmitting area. The light-shielding adhesive layer, at least partially positioned on the sidewall of the second via for the backlight and connected to the black tape, can also prevent light leakage from the backlight into the light-transmitting area. The combined effect of the light-shielding adhesive layer and the black tape effectively shields the first polarizer and the backlight, preventing light leakage from the display module into the light-transmitting area.
[0008] In some embodiments, there is a gap between the black tape and the sidewall of the first through hole, and the two do not contact each other.
[0009] In some embodiments, the coefficient of thermal expansion of the black tape is less than that of the light-shielding adhesive layer.
[0010] In some embodiments, the black tape is made of acrylic adhesive and polyethylene terephthalate. The light-shielding adhesive layer is made of hot melt adhesive.
[0011] In some embodiments, the thickness of the black tape is greater than the thickness of the first polarizer along a direction perpendicular to the non-display surface.
[0012] In some embodiments, along a direction parallel to the non-display surface, the edge of the second via is located inside the edge of the first via, creating a gap between the backlight and the display panel. At least a portion of the black tape fills the gap and is in contact with both the display panel and the backlight.
[0013] In some embodiments, the black tape includes an outer sidewall near the first polarizer and an inner sidewall away from the first polarizer. A light-shielding adhesive layer is attached to the surface of the black tape away from the display panel and to the inner sidewall of the black tape.
[0014] In some embodiments, the first polarizer includes a TAC film, a PVA film, and an APF film stacked sequentially, with the TAC film located on the side of the PVA film closer to the display panel and the APF film located on the side of the PVA film away from the display panel.
[0015] In some embodiments, the display module further includes a second polarizer disposed on the display surface. The display panel includes a length direction and a width direction parallel to the display surface, the length direction being perpendicular to the width direction, and the absorption axis of the second polarizer being parallel to the width direction.
[0016] The absorption axis of the PVA film in the first polarizer is parallel to the length direction, and the reflection axis of the APF film is parallel to the length direction.
[0017] In some embodiments, the display panel includes a first edge and a second edge opposite each other along the length direction, and a light-transmitting area is closer to the first edge than the second edge, the light-transmitting area corresponding to the middle position of the display panel along the width direction. The orthographic projection of the first via on the display panel is a circle, the edge of the circle includes two vertices, the line connecting the two vertices passes through the center of the circle and is parallel to the length direction.
[0018] In some embodiments, the black tape does not contact at least two vertices of the first via.
[0019] On the other hand, a display device is also provided, including a display module and a cover plate of any of the above embodiments, wherein the cover plate is located on the display surface of the display panel.
[0020] The above-described display device has the same structure and beneficial technical effects as the display module provided in some of the above embodiments, and will not be described again here. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in some embodiments of this application will be briefly described below. Obviously, the drawings described below are only drawings of some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams and are not actual dimensions of the products or actual processes of the methods involved in the embodiments of this application.
[0022] Figure 1 This is a schematic diagram of the structure of a display module provided in an embodiment of this application;
[0023] Figure 2 for Figure 1 The image shows a cross-sectional view of the module along section line AA'.
[0024] Figure 3 This is a magnified schematic diagram of a localized crack in a polarizer in a related technology.
[0025] Figure 4 for Figure 1 The diagram shown is a schematic diagram of the structure of the first polarizer in the display module;
[0026] Figure 5 This is a schematic diagram of the structure of a display device provided in an embodiment of this application;
[0027] Figure 6 A flowchart illustrating a method for manufacturing a display module provided in this application embodiment;
[0028] Figure 7 This application provides a schematic diagram of a black tape roll as an embodiment;
[0029] Figure 8 for Figure 7 A magnified view of a portion of the black tape roll shown. Detailed Implementation
[0030] The technical solutions in some embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments provided in this application are within the scope of protection of this application.
[0031] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as open and encompassing, that is, "including, but not limited to".
[0032] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this application, unless otherwise stated, "a plurality of" means two or more.
[0033] In describing some embodiments, the term "connection" and its derivative expressions may be used. The term "connection" should be interpreted broadly; for example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium. For example, in describing some embodiments, the term "connection" may be used to indicate that two or more components have direct physical or electrical contact with each other.
[0034] In addition, the use of “based on” implies openness and inclusivity, because processes, steps, calculations or other actions “based on” one or more of the stated conditions or values may in practice be based on additional conditions or values beyond those stated.
[0035] It should be understood that when a layer or element is referred to as being on another layer or substrate, it can mean that the layer or element is directly on the other layer or substrate, or that there is an intermediate layer between the layer or element and the other layer or substrate.
[0036] This document describes exemplary embodiments with reference to cross-sectional views, which are intended as idealized exemplary drawings. In the drawings, the thickness of the layers and the area of the regions are enlarged for clarity. Therefore, variations in shape relative to the drawings are contemplated due to, for example, manufacturing techniques and / or tolerances. Thus, exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but rather include shape deviations caused, for example, by manufacturing processes. For example, etched areas shown as rectangular would typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to show the actual shapes of the areas of the device, nor are they intended to limit the scope of the exemplary embodiments.
[0037] In recent years, with the trend towards thinner and lighter designs in electronic products, the polarizers of some products have gradually evolved from a double TAC (Tri-cellulose Acetate) structure to a single TAC structure. However, for single TAC polarizers, the single-layer TAC film offers limited protection for the PVA (polyvinyl alcohol) film. Furthermore, most front-facing camera holes are currently located in the middle of the top of the screen, resulting in significant stress concentration at the top and bottom apexes of the hole. Additionally, to accommodate the habit of wearing sunglasses when viewing screens in the European and American markets, some products shipped to these markets require a design with a 90° absorption axis for the upper polarizer and a 0° absorption axis for the lower polarizer. These combined design requirements make the corresponding positions at the top and bottom apexes of the camera hole weak points in the polarizer.
[0038] Extensive verification studies have revealed that, in the reliability temperature shock test, the polarizer of the aforementioned products will develop cracks at its weakest point, leading to product certification failure.
[0039] Based on this, this application provides a display module, such as... Figures 1-2 As shown, Figure 1 This is a schematic diagram of the structure of a display module provided in an embodiment of this application. Figure 2 for Figure 1 The image shows a cross-sectional view of the module along section line AA'.
[0040] like Figure 1 As shown, the display module 100 includes a display area Q1 and a light-transmitting area Q2 located within the display area Q1. For example, the light-transmitting area Q2 corresponds to the front-facing camera of the product, and ambient light can be received by the front-facing camera through the light-transmitting area Q2.
[0041] like Figure 2 As shown, the display module 100 also includes a display panel 10, a first polarizer 11, black tape 12, a backlight 13, and a light-shielding adhesive layer 14. The display panel 10 includes a display surface P1 and a non-display surface P2. The first polarizer 11 is disposed on the non-display surface P2 and includes a first via K1 located within the light-transmitting area Q2. The black tape 12 is disposed on the non-display surface P2. The orthographic projection of the black tape 12 on the display panel 10 is annular, and the orthographic projection of the black tape 12 on the display panel 10 is within the range of the orthographic projection of the first via K1 on the display panel 10, that is, the black tape 12 is disposed inside the first via K1 of the first polarizer 11.
[0042] Furthermore, the backlight 13 is disposed on the side of the first polarizer 11 away from the display panel 10. The backlight 13 includes a second via K2 located within the light-transmitting area Q2. It can be understood that the second via K2 and the first via K1 are both located in the light-transmitting area Q2, and the second via K2 is connected to the first via K1 so that ambient light can be received by the front-facing camera through the first via K1 and the second via K2. The light-shielding adhesive layer 14 is at least partially disposed on the sidewall of the second via K2 and is connected to the black tape 12.
[0043] For example, such as Figure 2 As shown, the backlight 13 includes a back plate 131, a frame 132, a reflective sheet 133, a light guide plate 134, a diffuser 135, a lower prism layer 136, and an upper prism layer 137. The back plate 131 and frame 132 serve to fix and support the backlight 13, providing mechanical strength and protection against dust and moisture intrusion. The light guide plate 134 guides and diffuses light, uniformly directing the light source to the display area Q1. It is understood that the side of the backlight 13 closest to the display panel 10 is its emitting surface; the more light emitted towards the emitting surface, the better the display effect.
[0044] During the transmission of light within the light guide plate 134, the light propagates in various directions. The reflector 133 can reflect the light propagating towards the non-light-emitting surface, causing it to return to the light guide plate 134 and exit towards the light-emitting surface, thereby increasing the amount of light emitted from the light-emitting surface and improving the utilization rate of the light source. Furthermore, the aforementioned reflection effect also helps to improve the uniformity of light distribution within the light guide plate 134.
[0045] The diffuser 135 is used to diffuse light, further homogenizing and scattering it to reduce uneven brightness and spot phenomena, making the light softer and more uniform. The lower prism layer 136 and the upper prism layer 137 are used to adjust the direction and distribution of light, converging the light in a specific direction, which helps to improve display brightness and viewing angle, so that the light emitted after passing through the upper prism layer 137 is compatible with the display panel 10.
[0046] The backplate 131 and the frame 132 are located on the side of the reflector 133, the light guide plate 134, the diffuser 135, the lower prism layer 136 and the upper prism layer 137 near the second opening K2, which can prevent light from leaking out from the second opening K2.
[0047] In related technologies, such as Figure 3 As shown, Figure 3This is a magnified schematic diagram of a crack in a polarizer in the related technology. To prevent light leakage at the vias of the polarizer 11' and the backlight, a ring of hot melt adhesive 1' (also known as "first coat") is usually applied to the sidewall of the via of the polarizer 11' and a ring of hot melt adhesive (also known as "second coat") is applied to the sidewall of the via of the backlight.
[0048] Hot melt adhesive needs to be applied at high temperatures. During the curing process, the hot melt adhesive shrinks in volume, which can stretch the polarizer 11' and cause it to tear. Furthermore, in the reliability temperature shock test, because the hot melt adhesive cycles between -40℃ and 80℃, its large thermal expansion characteristics cause significant thermal expansion and contraction. During this process, the displacement of the first coat of adhesive is much greater than the thermal expansion and contraction of the polarizer 11' itself. Therefore, the hot melt adhesive severely stretches the polarizer 11' along the through-hole sidewalls. Moreover, the polarizer 11' itself has a weaker ability to withstand stress at its weakest points; therefore, the first coat of adhesive will first tear the polarizer 11' at these weakest points, leading to macroscopic cracks.
[0049] In the embodiments of this application, the black tape 12 is an independent finished structure. The orthographic projection of the black tape 12 on the display panel 10 is a ring. Furthermore, the orthographic projection of the black tape 12 on the display panel 10 is located within the range of the orthographic projection of the first via K1 on the display panel 10. That is, the black tape 12 is disposed inside the first via K1 of the first polarizer 11.
[0050] The black tape 12 can be adhered to the display panel 10 at room temperature without significant volume changes that could stretch the first polarizer 11. Furthermore, in the reliability temperature shock test, the black tape 12 does not exhibit significant thermal expansion and contraction, preventing the black tape 12 from tearing the first polarizer 11 and thus avoiding cracks in the first polarizer 11.
[0051] Ambient light can pass through the inner side of the black tape 12 ring and be received by the front-facing camera. Furthermore, the black tape 12 is placed inside the first via K1 of the first polarizer 11, which can shield the sidewall of the first via K1, preventing light leakage from the first polarizer 11 to the light-transmitting area Q2, and also preventing ambient light from propagating into the first polarizer 11 and affecting the display effect.
[0052] The light-shielding adhesive layer 14 is at least partially disposed on the side wall of the second via K2 of the backlight 13 and is connected to the black tape 12. The light-shielding adhesive layer 14 can prevent the backlight 13 from leaking light into the light-transmitting area Q2. Furthermore, the connection between the light-shielding adhesive layer 14 and the black tape 12 can improve the structural stability of the two at the via. The two work together to form a light-shielding structure, shielding the first polarizer 11 and the backlight 13, improving the light leakage prevention capability at the via, and helping to ensure the camera's imaging effect.
[0053] In some embodiments, such as Figure 2 As shown, there is a gap between the black tape 12 and the sidewall of the first through hole K1, and the two do not contact each other.
[0054] That is, the black tape 12 is set within the orthographic projection range of the first through hole K1. The outer wall of the black tape 12 is not adjacent to the side wall of the first through hole K1. The black tape 12 and the first polarizer 11 are two completely independent entities with a gap between them. This gap provides space for the thermal expansion and contraction movement in the reliability temperature shock test. The two move thermally and contract independently without affecting each other, without squeezing or pulling each other, and there will be no problem of the first polarizer 11 being pulled. This can effectively prevent the first polarizer 11 from cracking.
[0055] For example, the display panel 10 includes a color filter substrate 101 and an array substrate 102 disposed opposite to each other. Near the boundary between the light-transmitting area Q2 and the display area Q1, the color filter substrate 101 also includes a black matrix BM. The orthographic projection of the black matrix BM near the light-transmitting area Q2 is annular. The black matrix BM includes an outer boundary near the display area Q1 and an inner boundary away from the display area Q1. Within the light-transmitting area Q2, the inner boundary of the black matrix BM corresponds to the camera aperture. The orthographic projection of the outer wall of the black tape 12 on the display panel 10 is located between the inner and outer boundaries of the black matrix BM. The black tape 12 is located on the side of the first polarizer 11 pointing towards the light-transmitting area Q2, and the black matrix BM is located on the side of the first polarizer 11 pointing towards the light-transmitting area Q2. The two are overlapped and staggered around the first polarizer 11, working together to prevent light leakage from the first polarizer 11 into the light-transmitting area Q2, which helps to ensure the shooting effect of the camera.
[0056] In some embodiments, the coefficient of thermal expansion of the black tape 12 is less than that of the light-shielding adhesive layer 14.
[0057] For example, the black tape 12 is made of acrylic adhesive and polyethylene terephthalate. The light-shielding adhesive layer 14 is made of hot melt adhesive.
[0058] The black tape 12 has a low coefficient of thermal expansion. At the same temperature, its expansion due to thermal contraction is also less than that of hot melt adhesive. Compared to related technologies, in the reliability temperature shock test, the deformation of the black tape 12 is smaller. Even when the outer wall of the black tape 12 is adjacent to the side wall of the first opening K1, the force it exerts on the first polarizer 11 is also smaller, preventing cracks in the first polarizer 11. When there is a gap between the black tape 12 and the side wall of the first through hole K1, in the reliability temperature shock test, due to the small deformation of the black tape 12, the expanded black tape 12 does not contact the first polarizer 11, and there is no interaction force between them. Therefore, the problem of the black tape 12 pulling on the first polarizer 11 is avoided, thus preventing cracks in the first polarizer 11.
[0059] In some embodiments, such as Figure 2 As shown, along the direction perpendicular to the non-display surface P2, the thickness of the black tape 12 is greater than the thickness of the first polarizer 11.
[0060] For example, the thickness of the first polarizer 11 is typically less than 0.1 mm, and the thickness of the black tape 12 can be controlled within the range of 0.1 mm to 0.15 mm, such as 0.1 mm, 0.12 mm, 0.13 mm, 0.14 mm, and 0.15 mm. The thickness of the black tape 12 is slightly greater than the thickness of the first polarizer 11, which can completely shield the light and prevent the first polarizer 11 from leaking light into the light-transmitting area Q2. The thickness of the black tape 12 should not be too large so as to provide a relatively flat surface for the assembly of the backlight 13 and prevent the backlight 13 from warping after assembly.
[0061] It is understandable that, since the light-shielding adhesive layer 14 is connected to the black tape 12, along the direction perpendicular to the display panel 10, when the light-shielding adhesive layer 14 and the black tape 12 are regarded as a combination, its thickness is greater than the thickness of the first polarizer 11. This combination can work together to achieve light shielding of the first polarizer 11. Even if the thickness of the black tape 12 is slightly less than the thickness of the first polarizer 11, the light-shielding adhesive layer 14 and the black tape 12 can still work together to prevent the first polarizer 11 from leaking light into the light-transmitting area Q2.
[0062] In some embodiments, such as Figure 2 As shown, along a direction parallel to the non-display surface P2, the edge of the second via K2 is located inside the edge of the first via K1, creating a gap between the backlight 13 and the display panel 10. At least a portion of the black tape 12 fills the gap and is in contact with the display panel 10 and the backlight 13.
[0063] Typically, the size of the second via K2 is smaller than the size of the first via K1. That is, along the direction perpendicular to the non-display surface P2, the orthogonal projection of the backlight 13 can completely cover the first polarizer 11. Based on this, it can be ensured that within the alignment error accuracy range, after the alignment assembly is completed, the orthogonal projection of the backlight 13 completely covers the first polarizer 11 to ensure the display effect.
[0064] In this embodiment, by setting black tape 12, the misalignment area between the backlight 13 and the first polarizer 11 near the light-transmitting area 12 is filled with black tape 12. The backlight 13 is assembled on the basis of black tape 12 and the first polarizer 11, which can prevent the backlight 13 from being suspended.
[0065] For example, the black tape 12 is a single-sided tape. Its adhesive side is used to attach to the display panel 10, and its non-adhesive side is used to set a release film, which facilitates the attachment process. For example, the black tape 12 and its release film are adsorbed using relevant equipment, and the black tape 12 is attached to the first opening K1. The black tape 12 is bonded to the display panel 10 through its adhesive side. Then the release film is removed. Since the adhesive force between the release film and the black tape 12 on the non-adhesive side is less than the adhesive force between the black tape 12 and the display panel 10 on the adhesive side, the release film can be removed more easily without pulling the black tape 12 and causing deformation of the black tape 12, which helps to ensure the yield rate.
[0066] Furthermore, the side of the backlight 13 closest to the display panel 10 is typically provided with double-sided light-shielding adhesive 130, such as... Figure 2 As shown, the double-sided light-shielding adhesive 130 is located at the edge of the backlight 13 near the second opening K2. The orthographic projection of the double-sided light-shielding adhesive 130 on the backlight 13 covers the adhesive frame 132 and partially covers the upper prism layer 137. On the one hand, the double-sided light-shielding adhesive 130 has a good light-shielding effect, which can prevent the backlight 13 from leaking light into the second opening K2. On the other hand, the double-sided light-shielding adhesive 130 has good adhesion. One side of the double-sided light-shielding adhesive 130 is bonded to the backlight 13, and the other side is bonded to the first polarizer 11 and the black tape 12, which helps to improve the assembly stability of the backlight 13 and the display panel 10.
[0067] Alternatively, the black tape 12 can be double-sided. After the backlight 13 is assembled, the black tape 12 is at least partially located between the backlight 13 and the display panel 10, with one side bonded to the display panel 10 and the other side bonded to the backlight 13. On one hand, the portion of the backlight 13 extending beyond the first polarizer 11, together with the black tape 12, helps improve the light-shielding effect on the first polarizer 11. On the other hand, the adhesive properties of the black tape 12 also help improve the assembly stability of the backlight 13 and the display panel 10. It is understandable that when the black tape 12 is double-sided, the design needs to be optimized so that the adhesive force between the black tape 12 and its corresponding release film is less than the adhesive force between the black tape 12 and the display panel 10, to ensure that the black tape 12 is reliably attached to the display panel 10 within the first opening K1.
[0068] In some embodiments, such as Figure 2 As shown, the black tape 12 includes an outer sidewall near the first polarizer 11 and an inner sidewall away from the first polarizer 11. The light-shielding adhesive layer 14 is connected to the surface of the black tape 12 away from the display panel 10 and is also connected to the inner sidewall of the black tape 12.
[0069] That is, after the backlight 13 is aligned and assembled, the light-shielding adhesive layer 14 applied in the second via K2 is piled up on the black tape 12 and bonded to the side wall of the backlight 13 at the second via K2. Part of the light-shielding adhesive layer 14 also extends from the surface of the black tape 12 to the area inside its inner side wall.
[0070] In the light-transmitting area Q2, the light-shielding adhesive layer 14 and the black tape 12 are completely fused together and adhered to each other. The two can be regarded as a combination and are attached to the side of the first polarizer 11 and the side of the backlight 13 to completely shield the first polarizer 11 and the backlight 13, prevent light leakage, and help ensure the shooting effect of the camera.
[0071] In some embodiments, such as Figure 4 As shown, Figure 4 for Figure 1 The diagram shows the structure of the first polarizer in the display module. The first polarizer 11 includes a TAC film, a PVA film and an APF film stacked in sequence. The TAC film is located on the side of the PVA film closer to the display panel 10, and the APF film is located on the side of the PVA film away from the display panel 10.
[0072] The PVA film includes a polyvinyl alcohol layer, which is the core material for achieving polarization. The TAC film includes cellulose triacetate, serving as a protective layer for the PVA film. It possesses excellent optical and mechanical properties, effectively preventing external damage to the PVA film. The APF film reflects light from the backlight 13 multiple times to improve light utilization, thereby significantly enhancing the display brightness of the display module.
[0073] In this embodiment, the first polarizer 11 adopts a single TAC structure, with the TAC film only disposed on the side of the PVA film close to the display panel 10, and bonded to the display panel 10 via a PSA film (i.e., pressure-sensitive adhesive). On the side of the PVA film close to the backlight 13, the PVA film is bonded to the APF film via a PSA film. Compared to the current dual TAC structure, the single TAC structure can reduce the thickness of the first polarizer 11, thereby reducing the overall thickness of the display module 100.
[0074] However, since the PVA film lacks a TAC film for protection on the side near the backlight 13, the overall structural strength of the first polarizer 11 is reduced, resulting in poor protection and making it prone to cracking. Therefore, in this embodiment, black tape 12 is used instead of the hot melt adhesive applied and cured around the sidewall of the first via K1 in related technologies. This ensures the light-shielding effect and also prevents the black tape 12 from applying force to the first polarizer 11 during the reliability temperature shock test, thereby preventing the PVA film from being stretched and cracking.
[0075] Combination Figure 1 The display panel 10 includes a length direction Y and a width direction X parallel to the display surface P1. The length direction Y is perpendicular to the width direction X. Typically, the length direction Y is 0° and the width direction X is 90°.
[0076] In some embodiments, such as Figure 2 As shown, the display module 100 also includes a second polarizer 15, which is disposed on the display surface P1. It can be understood that the core film layer in the second polarizer 15 that realizes the polarization function is still a PVA film. The second polarizer 15 can be a single TAC structure or a double TAC structure.
[0077] To achieve the display function, the absorption axis of the second polarizer 15 needs to be perpendicular to the absorption axis of the first polarizer 11. The direction of the absorption axis of the polarizer is also the direction of the molecular chains of its PVA film. For example, in some products, the absorption axis of the first polarizer 11 is parallel to the width direction X (i.e., 90°), and the absorption axis of the second polarizer 15 is parallel to the length direction Y (i.e., 0°). Alternatively, in other products, the absorption axis of the first polarizer 11 is parallel to the length direction Y (i.e., 0°), and the absorption axis of the second polarizer 15 is parallel to the width direction X (i.e., 90°).
[0078] However, in order to adapt to the habit of people in the European and American markets wearing sunglasses when looking at display screens, products shipped to the European and American markets must ensure that the absorption axis of the first polarizer 11 is 0° and the absorption axis of the second polarizer 15 is 90°.
[0079] That is, the absorption axis of the PVA film of the first polarizer 11 is parallel to the length direction Y, and the reflection axis of the APF film is parallel to the length direction Y. The absorption axis of the second polarizer 15 is parallel to the width direction X.
[0080] In some embodiments, such as Figure 1 As shown, the display panel 10 includes a first edge and a second edge that are opposite each other along the length direction Y. The first edge corresponds to the top of the display screen in the normal use state of the product and in the user's conventional perception, and the second edge corresponds to the bottom of the display screen in the normal use state of the product and in the user's conventional perception.
[0081] The light-transmitting area Q2 is closer to the first edge than the second edge, and corresponds to the middle position of the display panel 10 along the width direction X. This can be understood as the camera being positioned at the top center of the display screen in the corresponding product.
[0082] like Figure 1 As shown, the orthographic projection of the first via K1 onto the display panel 10 is a circle, and the edge of the circle includes two vertices, which are... Figure 1 The positions of the midpoint M1 and the midpoint M2 are opposite each other, and the line connecting the two vertices passes through the center of the circle and is parallel to the length direction Y.
[0083] Combination Figure 3As shown, when the absorption axis of the PVA film in the first polarizer 11 is parallel to the length direction Y, and the reflection axis of the APF film is also parallel to the length direction Y, the molecular chain direction of the PVA film is along its absorption axis, i.e., parallel to the length direction Y. Correspondingly, in the transmission axis direction (i.e., the width direction X) of the PVA film, there is a bond between molecular chains. The bonding force between molecular chains is relatively weak, resulting in poor resistance to stress and easy tearing. Similarly, the molecular chain direction of the APF film is along its reflection axis, i.e., parallel to the length direction Y. In the transmission axis direction (i.e., the width direction X) of the APF film, there is a bond between molecular chains. The bonding force between molecular chains is relatively weak, resulting in poor resistance to stress and easy tearing.
[0084] In related technologies, hot melt adhesive 1' is applied and cured around the opening of the first polarizer 11'. In a reliability temperature shock test, the force exerted on the first polarizer 11' by the thermal expansion and contraction of the hot melt adhesive 1' is dissipated along the length direction Y (molecular chain direction) by the stretching of the molecular chains. However, the stress along the width direction X is concentrated at the upper and lower vertices of the first opening K1 along the length direction X because the first opening K1 is centrally located on the first polarizer 11'. Since the stress is evenly distributed along the width direction X and is not dissipated by the deformation or displacement of the sidewalls of the first opening K1, the stress along the width direction X is concentrated at the upper and lower vertices of the first opening K1 along the length direction Y (and...). Figure 1 The positions of the midpoint M1 and the vertex M2 are relatively close to each other. Due to the weak bonding force between molecular chains in the width direction X of the first polarizer 11', stress will cause cracks in the first polarizer 11', and the cracks will spread along the length direction Y.
[0085] Based on this, in some embodiments, the black tape 12 does not contact at least the two vertices of the first through hole K1.
[0086] That is, in this embodiment, on the one hand, an independent finished black tape 12 is used instead of the hot melt adhesive applied in related technologies. The black tape 12 and the first polarizer 11 do not overlap and are two independent entities to reduce the impact of the thermal expansion and contraction of the black tape 12 on the first polarizer 11. On the other hand, for the stress concentration and weak resistance of the first polarizer 11, namely the two vertex positions mentioned above, further optimization design is carried out so that there is a gap between the black tape 12 and the first polarizer 11 at at least these two vertex positions (that is, the black tape 12 and the first polarizer 11 are disconnected on the non-display surface P2). For example, the orthographic projection of the first opening K1 is a circle and the orthographic projection of the black tape 12 is an elliptical ring. The major axis of the ellipse is parallel to the width direction X and the minor axis is parallel to the length direction Y. At this weak point, there is a spatial gap between the black tape 12 and the first polarizer 11. This gap provides space for the thermal expansion and contraction movement during the reliability temperature shock test, so that the expansion and contraction movement of the black tape 12 will at least not affect this weak point, thereby preventing the first polarizer 11 from cracking.
[0087] On the other hand, a display device is also provided, such as Figure 5 As shown, Figure 5 This is a schematic diagram of the structure of a display device provided in an embodiment of this application.
[0088] The display device 200 includes a display module 100 and a cover plate 16 according to any of the above embodiments. The cover plate 16 is located on the display surface P1 of the display panel 10. An optical adhesive layer 17 is also provided between the display module 100 and the cover plate 16. The optical adhesive layer 17 is used to bond the cover plate 16 to the side of the second polarizer 15 away from the display panel 10.
[0089] In this display device 200, black tape 12 is disposed within the area of the orthographic projection of the first via K1 of the first polarizer 11 onto the display panel 10. A light-shielding adhesive layer 14 is at least partially disposed on the sidewall of the backlight 13 on the second via K2 and is connected to the black tape 12. The light-shielding adhesive layer 14 and the black tape 12 work together to shield the first polarizer 11 and the backlight 13, effectively preventing light leakage from the display module 100 into the light-transmitting area Q2, which helps ensure the camera's imaging performance.
[0090] Furthermore, the black tape 12 does not overlap with the first polarizer 11. They are two independent entities. In the reliability temperature shock test, they expand and contract independently, and have almost no influence on each other. Therefore, the black tape 12 will not pull the first polarizer 11, thus preventing the first polarizer 11 from cracking.
[0091] Based on this, the display device 200 can be designed as a thin and light product with a single TAC structure polarizer, and can also meet the needs of users in the European and American markets who wear sunglasses to view the display screen.
[0092] The aforementioned display device 200 can be any device that displays either moving (e.g., video) or stationary (e.g., still images) text or images. More specifically, the embodiments described are contemplated to be implemented in or associated with a variety of electronic devices, such as (but not limited to) mobile phones, wireless devices, personal data assistants (PDAs), handheld or portable computers, GPS receivers / navigators, cameras, MP4 video players, camcorders, game consoles, watches, clocks, calculators, television monitors, flat panel displays, computer monitors, automotive displays (e.g., odometer displays, etc.), navigators, cockpit controllers and / or displays, displays of camera views (e.g., displays of rearview cameras in vehicles), electronic photographs, electronic billboards or signs, projectors, architectural structures, packaging and aesthetic structures (e.g., displays of images of a piece of jewelry), etc.
[0093] Furthermore, a method for manufacturing a display module is also provided, such as... Figure 6 As shown, Figure 6 This is a flowchart illustrating a method for manufacturing a display module according to an embodiment of this application.
[0094] Combination Figures 1-2 As shown, the display module 100 includes a display area Q1 and a light-transmitting area Q2 located within the display area Q1. The fabrication method includes the following steps S10 to S40:
[0095] Step S10: Attach a first polarizer 11 to the non-display surface P2 of the display panel 10. The first polarizer 11 includes a first via K1 located in the light-transmitting area Q2.
[0096] Step S20: Apply black tape 12 to the non-display surface P2 of the display panel 10. The orthographic projection of the black tape 12 on the display panel 10 is a ring and is located within the range of the orthographic projection of the first via K1 on the display panel 10.
[0097] For example, attaching black tape 12 to the non-display surface P2 of the display panel 10 includes the following steps S21 to S24:
[0098] Step S21: Provide a roll 120, a carrier film 121 disposed on the roll 120, and a black tape 12 disposed on the carrier film 121 near the roll 120.
[0099] For example, such as Figures 7-8 As shown, Figure 7This application provides a schematic diagram of a black tape roll as an embodiment. Figure 8 for Figure 7 A magnified view of a portion of the black tape roll shown.
[0100] Multiple black adhesive tapes 12 are provided on the roll material 120. The black adhesive tapes 12 are double-sided tapes, with one side bonded to the roll material 120 and the other side bonded to the carrier film 121. The carrier film 121 serves to support and protect the black adhesive tapes 12.
[0101] Step S22: Remove the carrier film 121 and black tape 12 from the roll 120.
[0102] For example, a machine-applied device is used to adsorb the carrier film 121 and the black tape 12 from the roll 120.
[0103] Step S23: Attach the black tape 12 to the non-display surface P2, with the carrier film 121 located on the side of the black tape 12 away from the display panel 10.
[0104] For example, the positioning system of the machine-applied device is used to capture the orthographic projection outline of the first via K1 and the orthographic projection outline of the black tape 12, and to accurately position them so that the black tape 12 is attached to the orthographic projection area of the first via K1.
[0105] Step S24: Remove the carrier membrane 121.
[0106] The carrier film 121 plays a supporting and bearing role in the process of absorbing and attaching the black tape 12. After the attachment is completed, the carrier film 121 is removed, and only the black tape is left to be attached to the non-display surface P2.
[0107] By using the attachment of a separate finished black adhesive tape 12 to replace the application and curing of hot melt adhesive in related technologies, the process can be simplified, modular production can be achieved, and the total preparation time can be reduced.
[0108] Step S30: A backlight 13 is provided on the side of the first polarizer 11 away from the display panel 10. The backlight 13 includes a second via K2 located in the light-transmitting area Q2.
[0109] Step S40: Form a light-shielding adhesive layer 14, which is at least partially located on the sidewall of the second via K2 and connected to the black tape 12.
[0110] For example, in combination Figure 2 The black tape 12 includes an outer sidewall near the first polarizer 11 and an inner sidewall away from the first polarizer 11. Forming the light-shielding adhesive layer 14 includes forming the light-shielding adhesive layer 14 on the sidewall of the second via K2, on the surface of the black tape 12 away from the display panel 10, and on the inner sidewall of the black tape 12.
[0111] For example, after the backlight 13 is aligned and assembled, hot melt adhesive is applied along the sidewall of the second via K2, and the hot melt adhesive is placed on the surface of the black tape 12 away from the display panel 10 and on the inner sidewall of the black tape 12. After curing, the light-shielding adhesive layer 14 formed is bonded to the black tape 12, which helps to ensure a good light-shielding effect.
[0112] The above-described preparation method is simple and easy to implement. Compared with related technologies, it no longer applies cured hot melt adhesive to the sidewall of the first through-hole K1. Instead, it uses a separate finished black adhesive tape 12 to shield the first polarizer 11 and ensure the camera's shooting effect. Based on this, the black adhesive tape 12 and the first polarizer 11 are two independent entities. In the reliability temperature shock test, they expand and contract independently with almost no mutual influence, preventing the black adhesive tape 12 from pulling on the first polarizer 11 and thus avoiding cracks in the first polarizer 11.
[0113] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A display module, characterized in that, Includes a display area and a light-transmitting area located within the display area; The display module includes: Display panel, including opposing display surfaces and non-display surfaces; A first polarizer is disposed on the non-display surface, and the first polarizer includes a first through hole located within the light-transmitting area; Black tape is applied to the non-display surface; the orthographic projection of the black tape on the display panel is annular and located within the range of the orthographic projection of the first via on the display panel. A backlight source is disposed on the side of the first polarizer away from the display panel, and the backlight source includes a second via located within the light-transmitting area; A light-shielding adhesive layer is at least partially disposed on the sidewall of the second through hole and is connected to the black tape.
2. The display module according to claim 1, characterized in that, There is a gap between the black tape and the sidewall of the first through hole, and the two do not contact each other.
3. The display module according to claim 1, characterized in that, The coefficient of thermal expansion of the black tape is less than that of the light-shielding adhesive layer.
4. The display module according to claim 3, characterized in that, The black tape is made of acrylic adhesive and polyethylene terephthalate. The material of the light-shielding adhesive layer includes hot melt adhesive.
5. The display module according to claim 1, characterized in that, Along a direction perpendicular to the non-display surface, the thickness of the black tape is greater than the thickness of the first polarizer.
6. The display module according to claim 1, characterized in that, Along a direction parallel to the non-display surface, the edge of the second via is located inside the edge of the first via, creating a gap between the backlight and the display panel. At least a portion of the black tape fills the gap and is in contact with the display panel and the backlight.
7. The display module according to claim 1, characterized in that, The black tape includes an outer wall near the first polarizer and an inner wall away from the first polarizer. The light-shielding adhesive layer is connected to the surface of the black tape away from the display panel and to the inner wall of the black tape.
8. The display module according to claim 1, characterized in that, The first polarizer comprises a TAC film, a PVA film, and an APF film stacked sequentially; The TAC film is located on the side of the PVA film closer to the display panel, and the APF film is located on the side of the PVA film away from the display panel.
9. The display module according to claim 8, characterized in that, The display module further includes a second polarizer, which is disposed on the display surface; The display panel includes a length direction and a width direction parallel to the display surface, the length direction being perpendicular to the width direction, and the absorption axis of the second polarizer being parallel to the width direction; The absorption axis of the PVA film of the first polarizer is parallel to the length direction, and the reflection axis of the APF film is parallel to the length direction.
10. The display module according to claim 9, characterized in that, The display panel includes a first edge and a second edge opposite each other along the length direction, and the light-transmitting area is closer to the first edge than the second edge; The light-transmitting area corresponds to the middle position of the display panel along the width direction; The first via is projected onto the display panel as a circle, the edge of which includes two vertices, the line connecting the two vertices passing through the center of the circle and parallel to the length direction.
11. The display module according to claim 10, characterized in that, The black tape does not contact at least two vertices of the first via.
12. A display device, characterized in that, It includes a display module and a cover plate as described in any one of claims 1 to 11, wherein the cover plate is located on the display surface of the display panel.