Display device

Abstract

A display device comprises a display panel and a peep-proof module. The peep-proof module is arranged on one side of the display surface of the display panel and overlaps the display surface. The peep-proof module comprises a first substrate, a second substrate, a third substrate, a fourth substrate, a first liquid crystal layer, a second liquid crystal layer, a first polaroid, a second polaroid and a third polaroid. The first liquid crystal layer is disposed between the first substrate and the second substrate. The second liquid crystal layer is arranged between the third substrate and the fourth substrate. The first polaroid is arranged between the first substrate and the display panel. The second polaroid is arranged between the second substrate and the third substrate. The third polaroid is arranged on the side, back to the third substrate, of the fourth substrate. At least two of the first substrate, the second substrate, the third substrate and the fourth substrate respectively have birefringence. The display device provided by the utility model is better in peep-proof performance and lighter and thinner in appearance.

Description

Technical Field

[0001] The present utility model relates to a display device, and particularly to a display device with an anti-peeping function. Background Art

[0002] Most of the substrates of current electronic anti-peeping films are glass substrates, and additional polarizers need to be provided on both opposite sides of the electronic anti-peeping film. In order to achieve a better anti-peeping effect, generally, two sets of electronic anti-peeping films are configured in the anti-peeping module. Therefore, the overall thickness and weight of the display device will inevitably increase significantly due to the additional electronic anti-peeping films, resulting in poor applicability in portable products.

[0003] The "Background Art" paragraph is only used to help understand the content of the present utility model. Therefore, the content disclosed in the "Background Art" paragraph may include some known technologies that are not known to those skilled in the art of the relevant technical field. The content disclosed in the "Background Art" paragraph does not represent the problems to be solved by the content or one or more embodiments of the present utility model, which have been known or recognized by those skilled in the art before the application of the present utility model. Summary of the Utility Model

[0004] The present utility model provides a display device with better anti-peeping performance and a thinner and lighter appearance.

[0005] Other objects and advantages of the present utility model can be further understood from the technical features disclosed in the present utility model.

[0006] To achieve one or part or all of the above objects or other objects, an embodiment of the present utility model provides a display device. The display device includes a display panel and an anti-peeping module. The anti-peeping module is disposed on one side of the display surface of the display panel and overlaps the display surface. The anti-peeping module includes a first substrate, a second substrate, a third substrate, a fourth substrate, a first liquid crystal layer, a second liquid crystal layer, a first polarizer, a second polarizer, and a third polarizer. The first substrate, the second substrate, the third substrate, and the fourth substrate are overlapped with each other. The first liquid crystal layer is disposed between the first substrate and the second substrate. The second liquid crystal layer is disposed between the third substrate and the fourth substrate. The first polarizer is disposed between the first substrate and the display panel. The second polarizer is disposed between the second substrate and the third substrate. The third polarizer is disposed on the side of the fourth substrate facing away from the third substrate. At least two of the first substrate, the second substrate, the third substrate, and the fourth substrate each have a birefringence.

[0007] Based on the above, in the display device according to an embodiment of the present invention, at least two substrates of the anti-peeping module each have birefringence. Therefore, in addition to improving the anti-peeping effect, it can effectively reduce the overall thickness and weight of the anti-peeping module, thereby improving the portability of the display device and its design flexibility in product applications.

[0008] In order to make the above features and advantages of the present invention more obvious and understandable, specific embodiments are hereinafter given and described in detail in conjunction with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 is a cross-sectional schematic view of a display device according to a first embodiment of the present invention.

[0010] Figure 2A is Figure 1 a distribution curve graph of the transmittance versus the viewing angle of the display device operating in the sharing mode and the anti-peeping mode respectively.

[0011] Figure 2B is a distribution curve graph of the transmittance versus the viewing angle of a display device of a comparative example operating in the sharing mode and the anti-peeping mode respectively.

[0012] Figure 3 is a cross-sectional schematic view of a display device according to a second embodiment of the present invention.

[0013] Figure 4 is a cross-sectional schematic view of a display device according to a third embodiment of the present invention.

[0014] Figure 5 is Figure 4 a distribution curve graph of the transmittance versus the viewing angle of the display device operating in the sharing mode and the anti-peeping mode respectively.

[0015] Figure 6 is a cross-sectional schematic view of a display device according to a fourth embodiment of the present invention.

[0016] Figure 7 is a cross-sectional schematic view of a display device according to a fifth embodiment of the present invention.

[0017] Figure 8 is Figure 7 a cross-sectional schematic view of another variant embodiment of the display device.

[0018] Figure 9 is a cross-sectional schematic view of a display device according to a sixth embodiment of the present invention.

[0019] Figure 10 is Figure 9 a distribution curve graph of the transmittance versus the viewing angle of the display device operating in the sharing mode and the anti-peeping mode respectively.

[0020] Description of the reference numerals:

[0021] 10, 10A, 10B, 10C, 10D, 10D”, 10E: Display device

[0022] 100, 100A, 100B, 100C, 100D, 100D”, 100E: Anti-peeping module

[0023] 110, 110A, 110B: First viewing angle switcher

[0024] 120, 120A, 120B: Second viewing angle switcher

[0025] 150: Water vapor barrier film

[0026] ADL1: First adhesive layer

[0027] ADL2: Second adhesive layer

[0028] CG: Glass cover plate

[0029] DP: Display panel

[0030] DS: Display surface

[0031] GAP1: First gap

[0032] GAP2: Second gap

[0033] GAP3: Third gap

[0034] GS1: First glass substrate

[0035] GS2: Second glass substrate

[0036] LCL1: First liquid crystal layer

[0037] LCL2: Second liquid crystal layer

[0038] PL1: First protective layer

[0039] PL2: Second protective layer

[0040] POL1: First polarizer

[0041] POL2, POL2-A: Second polarizer

[0042] POL3, POL3-A: Third polarizer

[0043] SUB1, SUB1-A: First substrate

[0044] SUB2: Second substrate

[0045] SUB3, SUB3-A: The third substrate

[0046] SUB4: The fourth substrate

[0047] t1a, t1b, t1c, t2a, t2b, t2c: Thicknesses Detailed implementation manners

[0048] Regarding the foregoing and other technical contents, features and effects of the present utility model, they will be clearly presented in the following detailed description of a preferred embodiment with reference to the accompanying drawings. The directional terms mentioned in the following embodiments, such as: up, down, left, right, front or rear, etc., are only with reference to the directions of the accompanying drawings. Therefore, the directional terms used are for illustration and not for limiting the present utility model.

[0049] Figure 1 is a cross-sectional schematic view of a display device according to a first embodiment of the present utility model. Figure 2A is Figure 1 a distribution curve graph of the transmittance versus the viewing angle of the display device operating in the sharing mode and the anti-peeping mode respectively. Figure 2B is a distribution curve graph of the transmittance versus the viewing angle of the display device of the comparative example operating in the sharing mode and the anti-peeping mode respectively.

[0050] Please refer to Figure 1 , the display device 10 includes a display panel DP and an anti-peeping module 100. The display panel DP has a display surface DS. The anti-peeping module 100 is disposed on one side of the display surface DS of the display panel DP and overlaps the display surface DS. The display panel DP is, for example, an organic light emitting diode (OLED) display panel, a micro light emitting diode (micro-LED) display panel, a mini light emitting diode (mini-LED) display panel, or other suitable self-luminous display panels. However, the present utility model is not limited thereto. In some embodiments, the display panel DP may also be a liquid crystal display panel, or other suitable non-self-luminous display panels.

[0051] In the present embodiment, the display device is adapted to operate in the anti-peeping mode and the sharing mode. First, it should be noted that when the light-emitting angle range of the anti-peeping module 100 is switched to the wide-angle range, the display device 10 is operating in the sharing mode with a larger viewing angle range. When the light-emitting angle range of the anti-peeping module 100 is switched to the narrow-angle range, the display device 10 is operating in the anti-peeping mode with a smaller viewing angle range.

[0052] Specifically, the anti-peeking module 100 includes a first substrate SUB1, a second substrate SUB2, a third substrate SUB3, a fourth substrate SUB4, a first liquid crystal layer LCL1, a second liquid crystal layer LCL2, a first polarizer POL1, a second polarizer POL2, and a third polarizer POL3 that are overlapped with each other. The first liquid crystal layer LCL1 is disposed between the first substrate SUB1 and the second substrate SUB2. The second liquid crystal layer LCL2 is disposed between the third substrate SUB3 and the fourth substrate SUB4. The first polarizer POL1 is disposed between the display panel DP and the first substrate SUB1. The second polarizer POL2 is disposed between the second substrate SUB2 and the third substrate SUB3. The third polarizer POL3 is disposed on a side of the fourth substrate SUB4 facing away from the third substrate SUB3.

[0053] From another perspective, the first substrate SUB1, the second substrate SUB2, and the first liquid crystal layer LCL1 can form a first viewing angle switch 110 of the anti-peeking module 100, and the third substrate SUB3, the fourth substrate SUB4, and the second liquid crystal layer LCL2 can form a second viewing angle switch 120 of the anti-peeking module 100. The first polarizer POL1 is located between the first viewing angle switch 110 and the display panel DP. The second polarizer POL2 is located between the first viewing angle switch 110 and the second viewing angle switch 120. The third polarizer POL3 is located on a side of the second viewing angle switch 120 facing away from the first viewing angle switch 110.

[0054] In this embodiment, the first viewing angle switch 110 and the second viewing angle switch 120 are, for example, bonded to each other in a direct bond manner, and the anti-peeking module 100 is, for example, fixed to the display panel DP in an air bond manner, but is not limited thereto. That is, a first gap GAP1 can be provided between the first viewing angle switch 110 and the display panel DP, and a second adhesive layer ADL2 (the first adhesive layer ADL1 is exposed in Figure 4 the embodiment). The material of the second adhesive layer ADL2, for example, includes an optically clear adhesive (OCA) or an optically clear resin (OCR), but is not limited thereto.

[0055] For example, the first polarizer POL1 and the second polarizer POL2 can be respectively attached to the surfaces of the first substrate SUB1 and the second substrate SUB2 of the first viewing angle switch 110 on the side facing away from the first liquid crystal layer LCL1, while the third polarizer POL3 can be attached to the surface of the fourth substrate SUB4 of the second viewing angle switch 120 on the side facing away from the second liquid crystal layer LCL2. In this embodiment, the first polarizer POL1 is, for example, a circular polarizer, and the second polarizer POL2 and the third polarizer POL3 are, for example, linear polarizers, but are not limited thereto.

[0056] It should be particularly noted that at least two of the first substrate SUB1, the second substrate SUB2, the third substrate SUB3, and the fourth substrate SUB4 have materials with birefringence. For example, in this embodiment, the materials of the first substrate SUB1 and the third substrate SUB3 include, for example, glass, while the materials of the second substrate SUB2 and the fourth substrate SUB4 can have birefringence and include Tri-acetyl Cellulose (TAC), Polymethyl methacrylate (PMMA), Cyclic olefin copolymer (COP), or Polycarbonate (PC).

[0057] Since the second substrate SUB2 and the fourth substrate SUB4 each have birefringence, they can have a phase delay compensation effect on non-normal incident light, so the anti-peeping effect of the anti-peeping module 100 can be further improved.

[0058] On the other hand, the thickness t1a of the second substrate SUB2 and the thickness t2a of the fourth substrate SUB4 can each be greater than or equal to 40 microns and less than or equal to 160 microns, for example, 100 microns. Since substrates made of birefringent materials can have a thinner thickness and lighter weight than glass substrates, using birefringent materials (such as TAC) to make the second substrate SUB2 and the fourth substrate SUB4 can effectively reduce the overall thickness and weight of the anti-peeping module 100.

[0059] In the anti-peeping module 100 of this embodiment, a first glass substrate GS1 may be provided between the first liquid crystal layer LCL1 and the second substrate SUB2, and a second glass substrate GS2 may be provided between the second liquid crystal layer LCL2 and the fourth substrate SUB4. However, the present invention is not limited thereto. In another variant embodiment, if the first substrate SUB1 and the third substrate SUB3 are made of birefringent materials, and the second substrate SUB2 and the fourth substrate SUB4 are made of glass, then the first glass substrate GS1 may be disposed between the first liquid crystal layer LCL1 and the first substrate SUB1, and the second glass substrate GS2 may be disposed between the second liquid crystal layer LCL2 and the third substrate SUB3.

[0060] To further thin the anti-peeping module 100, the sum of the thickness t1b of the first substrate SUB1 and the thickness t1c of the first glass substrate GS1, and the sum of the thickness t2b of the third substrate SUB3 and the thickness t2c of the second glass substrate GS2 may each be less than or equal to 200 microns. For example, the thickness t1b of the first substrate SUB1 and the thickness t1c of the first glass substrate GS1 may be a combination of 50 microns and 150 microns or a combination of 100 microns and 100 microns, and the thickness t2b of the third substrate SUB3 and the thickness t2c of the second glass substrate GS2 may be a combination of 50 microns and 150 microns or a combination of 100 microns and 100 microns, but not limited thereto.

[0061] In an anti-peeping module of a comparative example, its stacking structure is all similar to Figure 1 the anti-peeping module 100, and the difference is only that the respective thicknesses of its first substrate SUB1, third substrate SUB3, first glass substrate GS1, and second glass substrate GS2 are all 400 microns. Figure 2A Show the transmittance vs. viewing angle distribution curves when the anti-peeping module 100 of this embodiment operates in the sharing mode (S-mode) and the anti-peeping mode (P-mode) respectively. Figure 2B Show the transmittance vs. viewing angle distribution curves when the anti-peeping module of the comparative example operates in the sharing mode and the anti-peeping mode respectively.

[0062] From Figure 2A and Figure 2B it can be seen that for the anti-peeping module 100 with thinned thickness, its anti-peeping efficacy is still equivalent to that of the anti-peeping module of the comparative example (i.e., the one without thickness thinning). That is to say, the anti-peeping module 100 with thinned thickness can still maintain good anti-peeping performance.

[0063] Furthermore, in order to make Figure 1The display device 10 can be switched between the anti-peeking mode and the sharing mode in an electrically controlled manner. Two electrode layers (not shown) can be provided on opposite sides of the first liquid crystal layer LCL1 of the anti-peeking module 100, and two other electrode layers (not shown) can be provided on opposite sides of the second liquid crystal layer LCL2. In addition, the driving modes of the first liquid crystal layer LCL1 and the second liquid crystal layer LCL2 can be the same or different, and the driving modes include, for example, the twisted nematic (TN) mode or the electrically controlled birefringence (ECB) mode, but are not limited thereto.

[0064] Some other embodiments will be listed below to illustrate the present disclosure in detail. The same components will be labeled with the same symbols, and the description of the same technical content will be omitted. For the omitted part, please refer to the foregoing embodiments and will not be repeated hereinafter.

[0065] Figure 3 is a cross-sectional schematic view of a display device according to a second embodiment of the present invention. Please refer to Figure 3 In the display device 10A of the present embodiment, the overall thickness of the anti-peeking module 100A can be further thinned compared to Figure 1 the anti-peeking module 100. For example, in the present embodiment, the first viewing angle switch 110A does not have Figure 1 the first glass substrate GS1, and the second viewing angle switch 120A does not have Figure 1 the second glass substrate GS2. Accordingly, the overall weight and thickness of the anti-peeking module 100A can be further reduced.

[0066] Preferably, the sum of the thickness t1b of the first substrate SUB 1 made of glass and the thickness t1 a of the second substrate SUB2 made of a birefringent material (such as triacetyl cellulose) is less than or equal to 200 micrometers, and the sum of the thickness t2b of the third substrate SUB3 made of glass and the thickness t2a of the fourth substrate SUB4 made of a birefringent material (such as triacetyl cellulose) is less than or equal to 200 micrometers.

[0067] Since the other components of the anti-peeking module 100A in the present embodiment that are not mentioned are all similar to Figure 1 the anti-peeking module 100, for a detailed description, please refer to the relevant paragraphs of the foregoing embodiment and will not be repeated here.

[0068] Figure 4 is a cross-sectional schematic view of a display device according to a third embodiment of the present invention. Figure 5 is Figure 4 a graph showing the distribution of the transmittance with respect to the viewing angle of the display device operating in the sharing mode and the anti-peeking mode, respectively. Please refer to Figure 4The display device 10B of this embodiment is Figure 3 The main difference of the display device 10A is that the first substrate and the third substrate are made of different materials.

[0069] Specifically, in the anti-peeping module 100B of the present embodiment, the first substrate SUB1-A of the first viewing angle switch 110B and the third substrate SUB3 of the second viewing angle switch 120B are also made of a material having a birefringence index (e.g., TAC). For example, in the present embodiment, the thickness t1b of the first substrate SUB1-A, the thickness t1a of the second substrate SUB2, the thickness t2b of the third substrate SUB3-A, and the thickness t2a of the fourth substrate SUB4 can each be greater than or equal to 20 microns and less than or equal to 80 microns. Accordingly, the overall thickness and weight of the anti-peeping module 100B can be further reduced.

[0070] Figure 5 The distribution curves of the transmittance versus viewing angle of the privacy protection module 100B of this embodiment when operating in the sharing mode (S-mode) and the privacy protection mode (P-mode) are shown. Figure 2B and Figure 5 It can be seen that the anti-peeping performance of the thinned anti-peeping module 100B is still comparable to that of the anti-peeping module of the aforementioned comparative example (ie, the thickness is not thinned). In other words, the thinned anti-peeping module 100B can still maintain good anti-peeping performance.

[0071] On the other hand, in the present embodiment, the first polarizer POL1 is, for example, directly attached to the display panel DP, and the anti-peeping module 100B and the display panel DP are attached in a fully attached manner. That is, a first adhesive layer ADL1 may be provided between the first substrate SUB1-A of the anti-peeping module 100B and the display panel DP, and the material of the first adhesive layer ADL1 includes, for example, OCA or OCR, but is not limited thereto. In addition, in the present embodiment, a second adhesive layer ADL2 is provided between the second substrate SUB2 and the third substrate SUB3-A, and the second adhesive layer ADL2 is located between the second polarizer POL2 and the second substrate SUB2. That is, the second polarizer POL2 is not directly attached to the second substrate SUB2 of the first viewing angle switcher 110B, but is attached to the third substrate SUB3-A of the second viewing angle switcher 120B, and is attached to the second substrate SUB2 of the first viewing angle switcher 110B through the second adhesive layer ADL2.

[0072] Since the other components not mentioned in the anti-peeping module 100B of this embodiment are Figure 1 Similar to the anti-peeping module 100, detailed description can be found in the relevant paragraphs of the aforementioned embodiment, which will not be repeated here.

[0073] Figure 6It is a cross-sectional schematic view of a display device according to the fourth embodiment of the present invention. Please refer to Figure 6 , the difference between the display device 10C of this embodiment and the Figure 4 display device 10B is that the anti-peeping module 100C of the display device 10C further includes a moisture and water vapor barrier film 150. More specifically, in this embodiment, the moisture and water vapor barrier film 150 is disposed on the side of the third polarizer POL3 facing away from the fourth substrate SUB4, and the material of the moisture and water vapor barrier film 150 includes, for example, polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), or cyclic olefin polymer (COP).

[0074] Through the setting of the moisture and water vapor barrier film 150, in addition to enhancing the moisture and water vapor barrier ability of the anti-peeping module 100C, it can also slow down the shrinkage stress or expansion stress generated by the third polarizer POL3 in hot and cold or high temperature and high humidity environments, thereby avoiding the deformation of the thinned anti-peeping module 100C and affecting the flatness and integrity of its own structure. From another perspective, the setting of the moisture and water vapor barrier film 150 can effectively enhance the environmental tolerance of the thinned anti-peeping module 100C, thereby improving the operation reliability of the display device 10C in high temperature or hot and cold shock environments.

[0075] Figure 7 It is a cross-sectional schematic view of a display device according to the fifth embodiment of the present invention. Figure 8 It is Figure 7 a cross-sectional schematic view of another modified embodiment of the display device. Please refer to Figure 7 , the difference between the display device 10D of this embodiment and the Figure 4 display device 10B is that the anti-peeping module 100D of the display device 10D further includes a glass cover plate CG. More specifically, in this embodiment, the glass cover plate CG is disposed on the side of the third polarizer POL3 facing away from the fourth substrate SUB4, and the glass cover plate CG is fixed to the third polarizer POL3 in a manner of being adhered with a frame adhesive. That is, a third gap GAP3 may be provided between the glass cover plate CG and the third polarizer POL3.

[0076] Since the anti-peeping module 100D is disposed above the display panel DP and is easily pressed by the user or other external forces, the setting of the glass cover plate CG can avoid the problem of abnormal display caused by excessive pressing of the anti-peeping module 100D, such as the appearance of mura in the picture.

[0077] On the other hand, in the present embodiment, whether it is the adhesion between the first viewing angle switcher 110B and the second viewing angle switcher 120B or the adhesion between the anti-peeping module 100D and the display panel DP is carried out in the way of bonding with mouth-shaped adhesive. That is to say, a first gap GAP1 is provided between the first substrate SUB1-A of the anti-peeping module 100D and the display panel DP, and the first gap GAP1 exists between the first polarizer POL1 and the display panel DP. A second gap GAP2 is provided between the second substrate SUB2-A of the first viewing angle switcher 110B and the third substrate SUB3-A of the second viewing angle switcher 120B, and the second gap GAP2 exists between the second polarizer POL2 and the second substrate SUB2-A. However, the present invention is not limited thereto. In another modified embodiment, as Figure 8 shown, the first polarizer POL1 of the anti-peeping module 100D” of the display device 10D” can be directly attached to the display panel DP, and the adhesion between the anti-peeping module 100D” and the display panel DP is carried out in a full adhesion manner. That is to say, a first adhesive layer ADL1 can be provided between the first substrate SUB1-A of the anti-peeping module 100D” and the display panel DP.

[0078] Figure 9 is a cross-sectional schematic view of a display device according to the sixth embodiment of the present invention. Figure 10 is Figure 9 the distribution curve of the transmittance versus viewing angle of the display device respectively operating in the sharing mode and the anti-peeping mode. Please refer to Figure 9 , the main difference between the display device 10E of the present embodiment and the Figure 4 display device 10B is that the types of the second polarizer and the third polarizer are different.

[0079] Specifically, in the present embodiment, the materials of the second polarizer POL2-A and the third polarizer POL3-A may include lyotropic liquid crystal (LLC) or reactive mesogen liquid crystal (RMLC), and are formed on the third substrate SUB3-A and the fourth substrate SUB4 by coating. That is to say, the substrates in the current polarizer can be omitted for the second polarizer POL2-A and the third polarizer POL3-A of the present embodiment. Accordingly, the overall thickness and weight of the anti-peeping module 100E can be further reduced.

[0080] Figure 10 shows the distribution curves of the transmittance versus viewing angle of the anti-peeping module 100E of the present embodiment respectively operating in the sharing mode (S-mode) and the anti-peeping mode (P-mode). From Figure 2B and Figure 10It can be seen that the anti-peeping module 100E after thickness thinning still has the same anti-peeping efficacy as the anti-peeping module of the foregoing comparative example (i.e., the anti-peeping module with non-thinned thickness). That is to say, the anti-peeping module 100E after thickness thinning can still maintain good anti-peeping performance.

[0081] On the other hand, since the second polarizer POL2-A and the third polarizer POL3-A omit the setting of the traditional substrate, the shrinkage stress or expansion stress generated by the second polarizer POL2-A and the third polarizer POL3-A in a high-temperature or thermal shock environment can be greatly reduced. More specifically, the second polarizer POL2-A and the third polarizer POL3-A of this embodiment can be stress-free polarizers.

[0082] To prevent such stress-free polarizers from being damaged by unexpected external forces, the anti-peeping module 100E of this embodiment further includes a first protective layer PL1 on the side of the second polarizer POL2-A facing away from the third substrate SUB3-A, and a second protective layer PL2 on the side of the third polarizer POL3-A facing away from the fourth substrate SUB4. However, the present invention is not limited thereto. In another variant embodiment, the second polarizer POL2-A can be formed on the second substrate SUB2. Therefore, the first protective layer PL1 can be provided on the side of the second polarizer POL2-A facing away from the second substrate SUB2.

[0083] In summary, in the display device according to an embodiment of the present invention, at least two substrates of the anti-peeping module each have birefringence. Therefore, in addition to improving the anti-peeping effect, the overall thickness and weight of the anti-peeping module can be effectively reduced, thereby improving the portability of the display device and its design flexibility in product applications.

[0084] However, the above are only the preferred embodiments of the present invention, and the scope of implementation of the present invention cannot be limited thereby. That is, all simple equivalent changes and modifications made according to the claims of the present invention and the content of the present invention still fall within the scope covered by the patent of the present invention. In addition, any embodiment or claim of the present invention does not have to achieve all the purposes, advantages or features disclosed by the present invention. In addition, the abstract and the title (the name of the utility model) are only used to assist in the retrieval of patent documents and are not used to limit the scope of rights of the present invention. In addition, the terms "first", "second", etc. mentioned in this specification or claims are only used to name elements or distinguish different embodiments or scopes, and are not used to limit the upper or lower limits of the number of elements.

Claims

1. A display device, characterized in that: The display device includes a display panel and an anti-peeping module, wherein: The display panel has a display surface; and The anti-peeping module is disposed on one side of the display surface of the display panel and overlaps the display surface, wherein the anti-peeping module includes a first substrate, a second substrate, a third substrate, a fourth substrate, a first liquid crystal layer, a second liquid crystal layer, a first polarizer, a second polarizer, and a third polarizer, wherein: The first substrate, the second substrate, the third substrate and the fourth substrate are arranged to overlap each other; The first liquid crystal layer is disposed between the first substrate and the second substrate; The second liquid crystal layer is disposed between the third substrate and the fourth substrate; The first polarizer is disposed between the first substrate and the display panel; The second polarizer is disposed between the second substrate and the third substrate; and The third polarizer is arranged on a side of the fourth substrate facing away from the third substrate. At least two of the first substrate, the second substrate, the third substrate and the fourth substrate each have a birefringence index.

2. The display device according to claim 1, characterized in that The first substrate, the second substrate, the third substrate, and the fourth substrate each have a birefringence index.

3. The display device according to claim 2, characterized in that: The thickness of each of the first substrate, the second substrate, the third substrate, and the fourth substrate is greater than or equal to 20 micrometers and less than or equal to 80 micrometers.

4. The display device according to claim 2, characterized in that: The anti-peep module also includes a water-proof membrane, wherein; The water vapor blocking film is arranged on a side of the third polarizer facing away from the fourth substrate.

5. The display device according to claim 2, characterized in that: The anti-peep module further includes a glass cover, wherein: The glass cover is arranged on a side of the third polarizer facing away from the fourth substrate.

6. The display device according to claim 2, characterized in that: The second polarizer and the third polarizer are coated polarizers.

7. The display device according to claim 6, characterized in that: The second polarizer is formed on one of the second substrate and the third substrate, the third polarizer is formed on the fourth substrate, the second polarizer is provided with a first protective layer on a side facing away from the one of the second substrate and the third substrate, and the third polarizer is provided with a second protective layer on a side facing away from the fourth substrate.

8. The display device according to claim 1, characterized in that: The total thickness of the first substrate and the second substrate is less than or equal to 200 micrometers, and the total thickness of the third substrate and the fourth substrate is less than or equal to 200 micrometers.

9. The display device according to claim 8, characterized in that: The anti-peeping module further includes a first glass substrate and a second glass substrate, wherein: The first glass substrate is disposed between the first liquid crystal layer and the second substrate; and The second glass substrate is disposed between the second liquid crystal layer and the fourth substrate.

10. The display device according to claim 1, characterized in that: A first adhesive layer or a first gap is disposed between the first substrate and the display panel, and a second adhesive layer or a second gap is disposed between the second substrate and the third substrate.

Images