Anti-peeping module and display device

Abstract

The invention provides a peep-proof module and a display device. The peep-proof module comprises a first electric control visual angle switcher and a first polaroid. The first electric control view angle switcher comprises a first alignment layer, a second alignment layer, a first liquid crystal layer and a plurality of first spacers. The included angle between the first alignment direction of the first alignment layer and the second alignment direction of the second alignment layer ranges from 165 degrees to 195 degrees. The first spacer has a first refractive index greater than a first ordinary light refractive index of the first liquid crystal layer and less than a first extraordinary light refractive index of the first liquid crystal layer. When the absolute difference between the first refractive index and the first extraordinary light refractive index is smaller than 0.05, the first absorption axis of the first polaroid is perpendicular to the first alignment direction. When the absolute difference between the first refractive index and the first ordinary light refractive index is less than 0.05, the first absorption axis is parallel to the first alignment direction. The display quality of the peep-proof module and the display device provided by the invention is better.

Description

Technical Field

[0001] The present invention relates to a display device provided with an optical module, and more particularly to a display device provided with an anti-peeping module. Background Art

[0002] To provide display devices with privacy protection, a technical solution has been proposed that places an electrically controllable viewing angle control element above the display panel. Typically, this type of viewing angle control element is a liquid crystal device with electrically variable phase retardation. During the manufacturing process of a liquid crystal device, liquid crystal material is injected into the cavity between two transparent substrates to form a liquid crystal layer that modulates light. To control the thickness and uniformity of the liquid crystal layer, multiple spacers are placed within the cavity to control and maintain its height.

[0003] However, as the pixel size of display devices decreases (and pixel resolution increases), the impact of these spacers in the viewing angle control element on display quality will become increasingly severe. For example, if the display pixel size of a display panel is reduced to a size close to the size of the spacer in the viewing angle control element, some light will be deflected at the interface between the spacer and the liquid crystal layer. In other words, the spacer acts like a lens, causing different degrees of light diffusion in each sub-pixel. This can cause glare (uneven brightness or color of pixels) to the user, affecting the visual experience.

[0004] The "Background" section is intended only to facilitate understanding of the present invention. Therefore, the information disclosed in this section may contain information that is not already known to those skilled in the art. The information disclosed in this section does not imply that the information or the problems to be solved by one or more embodiments of the present invention were known or understood by those skilled in the art prior to the filing of this application. Summary of the Invention

[0005] The present invention provides an anti-peeping module and a display device, which have better display quality.

[0006] Other purposes and advantages of the present invention can be further understood from the technical features disclosed in the present invention.

[0007] To achieve one, some, or all of the above objectives, or other objectives, one embodiment of the present invention provides an anti-peeping module. The anti-peeping module includes a first electrically controlled viewing angle switcher, a first polarizer, and a second polarizer. The first electrically controlled viewing angle switcher includes a first substrate, a second substrate, a first alignment layer, a second alignment layer, a first liquid crystal layer, and a plurality of first spacers. The first substrate and the second substrate are stacked on each other. The first alignment layer is disposed on the first substrate and has a first alignment direction. The second alignment layer is disposed on the second substrate and has a second alignment direction. The angle between the first alignment direction and the second alignment direction is in a range from 165 degrees to 195 degrees. The first liquid crystal layer is disposed between the first alignment layer and the second alignment layer and includes a plurality of first liquid crystal molecules. Each of the first liquid crystal molecules has a first optical axis, a first extraordinary refractive index, and a first ordinary refractive index. The first extraordinary refractive index is greater than the first ordinary refractive index. The plurality of first spacers are disposed between the first substrate and the second substrate and each has a first refractive index. The first refractive index is greater than the first ordinary refractive index and less than the first extraordinary refractive index. The first polarizer is disposed on a side of the first liquid crystal layer where the first alignment layer is disposed, and has a first absorption axis. The axial direction of the first absorption axis is parallel to or perpendicular to the first alignment direction. The second polarizer is disposed on a side of the first liquid crystal layer where the second alignment layer is disposed, and has a second absorption axis. The axial direction of the second absorption axis is parallel to or perpendicular to the second alignment direction. When the absolute difference between the first refractive index and the first extraordinary light refractive index is less than 0.05, the axial direction of the first absorption axis is perpendicular to the first alignment direction. When the absolute difference between the first refractive index and the first ordinary light refractive index is less than 0.05, the axial direction of the first absorption axis is parallel to the first alignment direction.

[0008] To achieve one, some, or all of the above objectives, or other objectives, one embodiment of the present invention provides a display device. The display device includes a self-luminous display panel and a privacy protection module. The privacy protection module is disposed on one side of the display surface of the self-luminous display panel and includes a first electrically controlled viewing angle switcher, a first polarizer, and a second polarizer. The first electrically controlled viewing angle switcher includes a first substrate, a second substrate, a first alignment layer, a second alignment layer, a first liquid crystal layer, and a plurality of first spacers. The first and second substrates are stacked one on top of another. The first alignment layer is disposed on the first substrate and has a first alignment direction. The second alignment layer is disposed on the second substrate and has a second alignment direction. The angle between the first alignment direction and the second alignment direction is in a range from 165 degrees to 195 degrees. The first liquid crystal layer is disposed between the first and second alignment layers and includes a plurality of first liquid crystal molecules. Each of the first liquid crystal molecules has a first optical axis, a first extraordinary refractive index, and a first ordinary refractive index. The first extraordinary refractive index is greater than the first ordinary refractive index. The plurality of first spacers are disposed between the first and second substrates and each has a first refractive index. The first refractive index is greater than the first ordinary light refractive index and less than the first extraordinary light refractive index. The first polarizer is arranged on the side of the first liquid crystal layer where the first alignment layer is provided, and has a first absorption axis. The axial direction of the first absorption axis is parallel to or perpendicular to the first alignment direction. The second polarizer is arranged on the side of the first liquid crystal layer where the second alignment layer is provided, and has a second absorption axis. The axial direction of the second absorption axis is parallel to or perpendicular to the second alignment direction. When the absolute difference between the first refractive index and the first extraordinary light refractive index is less than 0.05, the axial direction of the first absorption axis is perpendicular to the first alignment direction. When the absolute difference between the first refractive index and the first ordinary light refractive index is less than 0.05, the axial direction of the first absorption axis is perpendicular to the first alignment direction.

[0009] Based on the above, in an anti-peeping module and display device according to one embodiment of the present invention, a plurality of first spacers define a space between the first substrate and the second substrate of the first electrically controlled viewing angle switcher to accommodate the first liquid crystal layer. The first refractive index of the first spacer is within the range between the first ordinary light refractive index and the first extraordinary light refractive index of the first liquid crystal layer. Because the configuration relationship between the first absorption axis of the first polarizer and the first alignment direction of the adjacent first alignment layer depends on the difference between the first refractive index of the first spacer and the first ordinary light refractive index or the first extraordinary light refractive index, the light path deflection angle when passing through the interface between the first spacer and the first liquid crystal layer can be effectively reduced. Accordingly, the user can avoid the phenomenon of uneven pixel color when viewing the display device, thereby improving the visual effect of the display image.

[0010] Although the present invention has been disclosed above with reference to the embodiments, they are not intended to limit the present invention. Any person skilled in the art may make slight changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a schematic cross-sectional view of a display device according to a first embodiment of the present invention.

[0012] Figure 2A yes Figure 1 Schematic diagram of the configuration relationship between the alignment direction of the alignment layer, the absorption axis of the polarizer and the double-sided anti-peeping axis.

[0013] Figure 2B yes Figure 2A Another variant implementation aspect of .

[0014] Figure 3 A schematic cross-sectional view of a display device according to a second embodiment of the present invention.

[0015] Figure 4A and Figure 4B yes Figure 3 Schematic diagram of the configuration relationship between the alignment direction of the alignment layer, the absorption axis of the polarizer and the double-sided anti-peeping axis.

[0016] Figure 4C yes Figure 4B Another variant implementation aspect of .

[0017] Figure 5 is a schematic cross-sectional view of a display device according to a third embodiment of the present invention.

[0018] Description of reference numerals:

[0019] 10, 10A, 20: Display device

[0020] 100: Self-luminous display panel

[0021] 100ds: Display surface

[0022] 200, 200A, 200B: Anti-peeping module

[0023] 210: First electronically controlled viewing angle switcher

[0024] 220, 220A: Second electronically controlled viewing angle switcher

[0025] 251, 252, 253: Compensation film

[0026] DPAX: Double-sided privacy axial

[0027] AD1 to AD4: first to fourth alignment directions

[0028] AL1: first alignment layer

[0029] AL2: Second alignment layer

[0030] AL3, AL3-A: third alignment layer

[0031] AL4, AL4-A: fourth alignment layer

[0032] AX1~AX3: First absorption axis~third absorption axis

[0033] EL1~EL4: first electrode layer~fourth electrode layer

[0034] H1, H2: height

[0035] LC1: first liquid crystal molecule

[0036] LC2: second liquid crystal molecule

[0037] LCL1: first liquid crystal layer

[0038] LCL2, LCL2-A: Second liquid crystal layer

[0039] OA1: First optical axis

[0040] OA2: Second optical axis

[0041] OX: Optical axis

[0042] POL1: The first polarizer

[0043] POL2: Second polarizer

[0044] POL3: third polarizer

[0045] SP1: First interstitial

[0046] SP2: Second interstitial

[0047] SPD: Single-sided privacy protection direction

[0048] SUB1~SUB4:1st to 4th substrates

[0049] SX: Slow axis

[0050] WP1: Quarter Wave Plate

[0051] WP2: Half-wave plate

[0052] Z: Direction

[0053] α1, α2, α3, α4, γ1, γ2, β2, β3, θ: angle. DETAILED DESCRIPTION

[0054] The aforementioned technical contents, features, and functions of the present invention will be more clearly understood in the following detailed description of a preferred embodiment with reference to the accompanying drawings. Directional terms such as up, down, left, right, front, and back mentioned in the following embodiments are merely references to the accompanying drawings. Therefore, the directional terms used are for illustrative purposes only and are not intended to limit the present invention.

[0055] Figure 1 is a schematic cross-sectional view of a display device according to a first embodiment of the present invention. Figure 2A yes Figure 1 Schematic diagram of the configuration relationship between the alignment direction of the alignment layer, the absorption axis of the polarizer and the double-sided anti-peeping axis. Figure 2B yes Figure 2A Another variant implementation. In particular, Figure 2A and Figure 2B The angular arrangement relationship shown is, for example, the angular arrangement relationship of the display device 10 in the plan view direction (eg, direction Z).

[0056] Please refer to Figure 1 The display device 10 includes a self-luminous display panel 100 and an anti-peeping module 200. The anti-peeping module 200 is disposed on a side of the display surface 100ds of the self-luminous display panel 100 (e.g., the surface where the display light beam leaves the self-luminous display panel 100), and includes a first electrically controlled viewing angle switcher 210, a second electrically controlled viewing angle switcher 220, a first polarizer POL1, a second polarizer POL2, and a third polarizer POL3. The first electrically controlled viewing angle switcher 210 is disposed between the second electrically controlled viewing angle switcher 220 and the self-luminous display panel 100. The first polarizer POL1 is disposed between the first electrically controlled viewing angle switcher 210 and the self-luminous display panel 100. The second polarizer POL2 is disposed between the first electrically controlled viewing angle switcher 210 and the second electrically controlled viewing angle switcher 220. The third polarizer POL3 is disposed on a side of the second electrically controlled viewing angle switch 220 that faces away from the first electrically controlled viewing angle switch 210 (i.e., the second electrically controlled viewing angle switch 220 is disposed between the third polarizer POL3 and the first electrically controlled viewing angle switch 210). It should be noted that the self-luminous display panel 100 and the first polarizer POL1 are bonded, for example, in a non-full bonding manner, such as air bonding, while the remaining optical components are bonded, for example, in a full bonding manner.

[0057] More specifically, a first polarizer POL1, a first electrically controlled viewing angle switcher 210, a second polarizer POL2, a second electrically controlled viewing angle switcher 220, and a third polarizer POL3 are sequentially stacked on the display surface 100ds of the self-luminous display panel 100 along a direction Z. The direction Z is, for example, perpendicular to the display surface 100ds.

[0058] The self-luminous display panel 100 is, for example, an organic light emitting diode (OLED) display panel, a micro light emitting diode (micro-LED) display panel, or a sub-millimeter light emitting diode (mini-LED) display panel, but is not limited thereto.

[0059] The first electrically controlled viewing angle switcher 210 includes a first substrate SUB1, a second substrate SUB2, a first liquid crystal layer LCL1, a first alignment layer AL1, and a second alignment layer AL2. The first alignment layer AL1 is disposed on the first substrate SUB1 and is located between the first liquid crystal layer LCL1 and the first polarizer POL1 (or between the first liquid crystal layer LCL1 and the first substrate SUB1). The second alignment layer AL2 is disposed on the second substrate SUB2 and is located between the first liquid crystal layer LCL1 and the second polarizer POL2 (or between the first liquid crystal layer LCL1 and the second substrate SUB2). The first liquid crystal layer LCL1 is disposed between the first alignment layer AL1 and the second alignment layer AL2.

[0060] The second electrically controlled viewing angle switcher 220 includes a third substrate SUB3, a fourth substrate SUB4, a second liquid crystal layer LCL2, a third alignment layer AL3, and a fourth alignment layer AL4. The third alignment layer AL3 is disposed on the third substrate SUB3 and is located between the second liquid crystal layer LCL2 and the second polarizer POL2 (or between the second liquid crystal layer LCL2 and the third substrate SUB3). The fourth alignment layer AL4 is disposed on the fourth substrate SUB4 and is located between the second liquid crystal layer LCL2 and the third polarizer POL3 (or between the second liquid crystal layer LCL2 and the fourth substrate SUB4). The second liquid crystal layer LCL2 is disposed between the third alignment layer AL3 and the fourth alignment layer AL4.

[0061] The substrate material of the electrically controlled viewing angle switch may include glass, triacetate (TAC), cyclo-olefin polymer (COP), polycarbonate (PC), polymethyl methacrylate (PMMA), polyimide (PI), other suitable polymers or plates with phase delay (such as stretched compensation film).

[0062] It is particularly noted that the two alignment layers of each electrically controlled viewing angle switch are configured to determine the arrangement state of the liquid crystal layer in a natural state (for example, not affected by an electric field). In order to drive the liquid crystal layer, each electrically controlled viewing angle switch may further include two electrode layers, which are respectively arranged on opposite sides of the liquid crystal layer. When the two electrode layers are enabled and have a potential difference, the plurality of liquid crystal molecules in the liquid crystal layer are deflected by the electric field formed between the two electrode layers. The electrode layer is, for example, a light-transmitting electrode, and the material of the light-transmitting electrode may include a metal oxide, such as indium tin oxide, indium zinc oxide, aluminum tin oxide, aluminum zinc oxide, or other suitable oxides, or a stacked layer of at least two of the above, but is not limited thereto.

[0063] For example, in this embodiment, the first electrically controlled viewing angle switch 210 further includes a first electrode layer EL1 and a second electrode layer EL2, which are disposed on the first substrate SUB1 and the second substrate SUB2, respectively, and are used to drive the plurality of first liquid crystal molecules LC1 of the first liquid crystal layer LCL1 to rotate. Similarly, the second electrically controlled viewing angle switch 220 further includes a third electrode layer EL3 and a fourth electrode layer EL4, which are disposed on the third substrate SUB3 and the fourth substrate SUB4, respectively, and are used to drive the plurality of second liquid crystal molecules LC2 of the second liquid crystal layer LCL2 to rotate.

[0064] By adjusting the voltage applied between the first electrode layer EL1 and the second electrode layer EL2 of the first electrically controlled viewing angle switch 210 and the voltage applied between the third electrode layer EL3 and the fourth electrode layer EL4 of the second electrically controlled viewing angle switch 220, the display device 10 can be switched between the sharing mode and the privacy mode. For example, when a first voltage is applied between the first electrode layer EL1 and the second electrode layer EL2 and / or a third voltage is applied between the third electrode layer EL3 and the fourth electrode layer EL4, the display device 10 operates in the privacy mode. When a second voltage is applied between the first electrode layer EL1 and the second electrode layer EL2, and a fourth voltage is applied between the third electrode layer EL3 and the fourth electrode layer EL4, the display device 10 operates in the sharing mode.

[0065] In the present invention, the liquid crystal layers of the electrically controlled viewing angle switch can be driven in either a twisted-nematic (TN) mode or an electrically controlled birefringence (ECB) mode. For example, in this embodiment, both the first electrically controlled viewing angle switch 210 and the second electrically controlled viewing angle switch 220 are driven in the ECB mode, and both the first liquid crystal layer LCL1 and the second liquid crystal layer LCL2 are, for example, positive-type liquid crystals.

[0066] Please also refer to Figure 1 and Figure 2A In this embodiment, the first electrically controlled viewing angle switch 210 and the second electrically controlled viewing angle switch 220 both have the same double-sided privacy protection axis DPAX that is perpendicular to the direction Z. In other words, both electrically controlled viewing angle switches can allow the display device 10 to have a privacy protection effect within the viewing angle range on both sides along the double-sided privacy protection axis DPAX. In detail, the double-sided privacy protection axis DPAX includes the same dimension (e.g. Figure 2A The horizontal dimension of the image has a viewing angle of 90 degrees to -90 degrees, where the viewing angle 0 degree is the 90 degree direction and the -90 degree direction opposite to each other in the positive viewing direction (e.g., direction Z). Figure 2A The direction to the right of the middle, and the -90 degree direction is towards Figure 2A In the left direction.

[0067] In this embodiment, the angle α1 between the first alignment direction AD1 of the first alignment layer AL1 and the -90-degree direction of the bilateral privacy protection axis DPAX can be 90 degrees. The angle α2 between the second alignment direction AD2 of the second alignment layer AL2 and the -90-degree direction of the bilateral privacy protection axis DPAX can be 95 degrees. That is, the angle γ1 between the first alignment direction AD1 and the second alignment direction AD2 is 175 degrees, but is not limited to this. In other embodiments, the angle between the first alignment direction AD1 and the second alignment direction AD2 can range from 165 degrees to 195 degrees.

[0068] Similarly, the angle α3 between the third alignment direction AD3 of the third alignment layer AL3 and the -90-degree direction of the bilateral privacy protection axis DPAX can be 95 degrees. The angle α4 between the fourth alignment direction AD4 of the fourth alignment layer AL4 and the -90-degree direction of the bilateral privacy protection axis DPAX can be 90 degrees. That is, the angle γ2 between the third alignment direction AD3 and the fourth alignment direction AD4 is 175 degrees, but is not limited to this. In other embodiments, the angle between the third alignment direction AD3 and the fourth alignment direction AD4 can range from 165 degrees to 195 degrees.

[0069] More specifically, in this embodiment, the first alignment direction AD1 and the fourth alignment direction AD4 are parallel to each other and perpendicular to the double-sided privacy protection axis DPAX, and the second alignment direction AD2 is parallel to the third alignment direction AD3 .

[0070] In this embodiment, the first absorption axis AX1 of the first polarizer POL1 may be oriented perpendicular to the first alignment direction AD1, while the third absorption axis AX3 of the third polarizer POL3 may be oriented perpendicular to the fourth alignment direction AD4. That is, the first absorption axis AX1 and the third absorption axis AX3 are oriented parallel to each other. The angle β2 between the -90-degree direction of the double-sided privacy protection axis DPAX and the second absorption axis AX2 of the second polarizer POL2 is, for example, 5 degrees, but is not limited thereto.

[0071] Furthermore, each of the plurality of first liquid crystal molecules LC1 of the first liquid crystal layer LCL1 has a first optical axis OA1, a first extraordinary refractive index in a direction parallel to the first optical axis OA1, and a first ordinary refractive index in a direction perpendicular to the first optical axis OA1. Each of the plurality of second liquid crystal molecules LC2 of the second liquid crystal layer LCL2 has a second optical axis OA2, a second extraordinary refractive index in a direction parallel to the second optical axis OA2, and a second ordinary refractive index in a direction perpendicular to the second optical axis OA2.

[0072] In particular, Figure 2A The first optical axis OA1 shown in FIG. 5 is the first optical axis OA1 of the first liquid crystal molecule LC1 in the first liquid crystal layer LCL1 that is closer to the first alignment layer AL1 (or the first polarizer POL1 ) (eg, the molecular long axis of the first liquid crystal molecule LC1 ). Figure 2A The second optical axis OA2 shown in FIG. 5 is the second optical axis OA2 of the second liquid crystal molecule LC2 in the second liquid crystal layer LCL2 that is closer to the third alignment layer AL3 (or the second polarizer POL2 ).

[0073] To control the thickness and uniformity of the first and second liquid crystal layers LCL1 and LCL2, the first electrically controlled viewing angle switcher 210 further includes a plurality of first spacers SP1 between the first and second substrates SUB1 and SUB2. The second electrically controlled viewing angle switcher 220 further includes a plurality of second spacers SP2 between the third and fourth substrates SUB3 and SUB4. The first and second spacers SP1 and SP2 have first and second refractive indices, respectively. The first refractive index is greater than the first ordinary refractive index and less than the first extraordinary refractive index, while the second refractive index is greater than the second ordinary refractive index and less than the second extraordinary refractive index. Preferably, the width of each of the first and second spacers SP1 and SP2 along any direction perpendicular to the Z direction is less than 15 μm.

[0074] For example, in this embodiment, the absolute difference between the first refractive index and the first extraordinary refractive index is less than 0.05, and the absolute difference between the second refractive index and the second extraordinary refractive index is less than 0.05. Therefore, by arranging the first absorption axis AX1 of the first polarizer POL1 perpendicular to the first alignment direction AD1, the difference in refractive index between the first spacer SP1 and the first liquid crystal layer LCL1 regarding the polarization direction of light (not shown) passing through the first polarizer POL1 is less than 0.05. Consequently, light does not experience significant path deflection when passing through the interface between the first spacer SP1 and the first liquid crystal layer LCL1. Similarly, by arranging the second absorption axis AX2 of the second polarizer POL2 perpendicular to the third alignment direction AD3, the difference in refractive index between the second spacer SP2 and the second liquid crystal layer LCL2 regarding the polarization direction of light (not shown) passing through the second polarizer POL2 is less than 0.05. Consequently, light does not experience significant path deflection when passing through the interface between the second spacer SP2 and the second liquid crystal layer LCL2. This prevents users from noticing pixel color unevenness caused by light deflection at the interface between the spacer and the liquid crystal layer when viewing the display device 10 , or from observing flickering when changing viewing angles, thereby improving the visual effect of the display image.

[0075] However, the present invention is not limited thereto. In another variant embodiment, the absolute difference between the first refractive index of the first spacer SP1 and the first ordinary refractive index may be less than 0.05, and the absolute difference between the second refractive index of the second spacer SP2 and the second ordinary refractive index may be less than 0.05. Therefore, in order to avoid the problem of uneven pixel color when the user is viewing the displayed image, the axial direction of the first absorption axis AX1 of the first polarizer POL1 and the axial direction of the third absorption axis AX3 of the third polarizer POL3 may be parallel to the first alignment direction AD1, and the second absorption axis AX2 of the second polarizer POL2 may be parallel to the third alignment direction AD3 (e.g. Figure 2B shown).

[0076] It should be noted that, in the aforementioned variant embodiment, the second voltage applied to the first electrode layer EL1 and the second electrode layer EL2 of the first electrically controlled viewing angle switcher 210 in sharing mode may be higher than the first voltage applied in anti-peeping mode, and the fourth voltage applied to the third electrode layer EL3 and the fourth electrode layer EL4 of the second electrically controlled viewing angle switcher 220 in sharing mode may be higher than the third voltage applied in anti-peeping mode. The first liquid crystal layer LCL1 and the second liquid crystal layer LCL2 are both, for example, positive liquid crystals. When the display device 10 operates in sharing mode, the axial direction of the molecular long axes of the first liquid crystal molecules LC1 and the second liquid crystal molecules LC2 generally tends to align along direction Z, for example. Therefore, the absolute difference in refractive index between the spacer and the liquid crystal layer in directions perpendicular to direction Z does not differ significantly, further improving pixel color non-uniformity caused by light path deflection at the interface between the spacer and the liquid crystal layer.

[0077] It is worth mentioning that in order to further improve the aforementioned pixel color non-uniformity problem caused by the spacer, preferably, the absolute difference between the ordinary ray refractive index and the extraordinary ray refractive index of each of the first liquid crystal layer LCL1 and the second liquid crystal layer LCL2 can be less than 0.12, and the height of the spacer along the stacking direction (e.g., direction Z) of the two adjacent substrates (e.g., direction Z) is less than 0.12. Figure 1 The height H1 and the height H2 may be greater than 5 μm and less than 10 μm, but is not limited thereto.

[0078] Furthermore, in this embodiment, the anti-peeping module 200 may further selectively include a compensation film 251 and a compensation film 252. The compensation film 251 is arranged between the first polarizer POL1 and the first liquid crystal layer LCL1, and the compensation film 252 is arranged between the third polarizer POL3 and the second liquid crystal layer LCL2. The out-of-plane phase retardation (Rth) of the compensation film 251 and the compensation film 252 may be in the range of 100nm to 500nm. In this embodiment, the out-of-plane phase retardation of the compensation film 251 and the compensation film 252 is, for example, 280nm. On the other hand, a quarter-wave plate WP1 may further be provided between the first polarizer POL1 of the anti-peeping module 200 and the self-luminous display panel 100. The angle between the optical axis OX of the quarter-wave plate WP1 and the first absorption axis AX1 of the first polarizer POL1 is 45 degrees.

[0079] It is worth noting that in this embodiment, a reflective polarizing layer (not shown) or a metal wire grid polarizing layer may be disposed between the second polarizer POL2 and the third substrate SUB3, but the present invention is not limited thereto. Accordingly, when the display device 10 operates in privacy protection mode, ambient light within the privacy protection viewing angle range is reflected by the reflective polarizing layer, resulting in a lower contrast ratio for the display image within the privacy protection viewing angle range, thereby further enhancing the privacy protection effect.

[0080] The following will list some other embodiments to illustrate the present disclosure in detail, wherein the same components will be marked with the same symbols, and the description of the same technical content will be omitted. For the omitted parts, please refer to the above embodiments and will not be repeated below.

[0081] Figure 3 A schematic cross-sectional view of a display device according to a second embodiment of the present invention. Figure 4A and Figure 4B yes Figure 3 Schematic diagram of the configuration relationship between the alignment direction of the alignment layer, the absorption axis of the polarizer and the double-sided anti-peeping axis. Figure 4C yes Figure 4B Another variant implementation. In particular, Figure 4A 、 Figure 4B and Figure 4C The angular arrangement relationship shown is, for example, the angular arrangement relationship of the display device 20 in the top view direction (eg, direction Z).

[0082] Please refer to Figure 3 、 Figure 4A and Figure 4B The display device 20 of this embodiment is Figure 1 The primary difference between the display device 10 and the current one lies in the different driving methods of the second electrically controlled viewing angle switcher. In this embodiment, the second liquid crystal layer LCL2-A of the second electrically controlled viewing angle switcher 220A of the privacy protection module 200A is driven, for example, in a twisted nematic (TN) mode. Specifically, the third alignment direction AD3 of the third alignment layer AL3-A of the second electrically controlled viewing angle switcher 220A is perpendicular to the fourth alignment direction AD4 of the fourth alignment layer AL4-A. In other words, the angle γ2 between the third alignment direction AD3 and the fourth alignment direction AD4 is 90 degrees.

[0083] Of particular note, the second electrically controlled viewing angle switch 220A has a single-sided privacy protection direction SPD perpendicular to the direction Z, and the single-sided privacy protection direction SPD is parallel to the -90-degree direction of the bilateral privacy protection axis DPAX of the first electrically controlled viewing angle switch 210, but the present invention is not limited thereto. More specifically, the first electrically controlled viewing angle switch 210 allows the display device 20 to have a privacy protection effect within the viewing angle range on both sides along the bilateral privacy protection axis DPAX, while the second electrically controlled viewing angle switch 220A allows the display device 20 to have a privacy protection effect within the viewing angle range on one side along the single-sided privacy protection direction SPD.

[0084] The angles α3 between the third alignment direction AD3 of the third alignment layer AL3-A and the fourth alignment direction AD4 of the fourth alignment layer AL4-A and the single-sided privacy protection direction SPD are each within a range of 40 to 50 degrees or 130 to 140 degrees. For example, in this embodiment, the angle α3 between the third alignment direction AD3 and the single-sided privacy protection direction SPD may be 45 degrees, and the angle α4 between the fourth alignment direction AD4 and the single-sided privacy protection direction SPD may be 135 degrees.

[0085] On the other hand, the second absorption axis AX2 of the second polarizer POL2 may be axially parallel to the third alignment direction AD3 of the third alignment layer AL3-A, and the third absorption axis AX3 of the third polarizer POL3 may be axially parallel to the fourth alignment direction AD4 of the fourth alignment layer AL4-A, but the present invention is not limited thereto. In other embodiments, the second absorption axis AX2 may be axially perpendicular to the third alignment direction AD3, and the third absorption axis AX3 may be axially perpendicular to the fourth alignment direction AD4.

[0086] In this embodiment, the second absorption axis AX2 of the second polarizer POL2 may be perpendicular to the third absorption axis AX3 of the third polarizer POL3, and the angles between the second absorption axis AX2 and the third absorption axis AX3 and the single-side privacy protection direction SPD are within a range of 40 to 50 degrees or 130 to 140 degrees. For example, in this embodiment, the angle β2 between the second absorption axis AX2 and the single-side privacy protection direction SPD may be 135 degrees, and the angle β3 between the third absorption axis AX3 and the single-side privacy protection direction SPD may be 45 degrees.

[0087] Since the configuration relationship between the first electrically controlled viewing angle switch 210 and the first polarizer POL1 of this embodiment is similar to Figure 1 The first electrically controlled viewing angle switch 210 and the first polarizer POL1 are described in detail in the relevant paragraphs of the aforementioned embodiment and will not be repeated here.

[0088] In this embodiment, the privacy protection module 200A may further optionally include a half-wave plate WP2, which is disposed between the first electrically controlled viewing angle switch 210 and the second electrically controlled viewing angle switch 220A, and the half-wave plate WP2 has a slow axis SX. It is particularly noteworthy that when the absolute difference between the first refractive index of the first spacer SP1 and the first extraordinary light refractive index of the first liquid crystal molecule LC1 is less than 0.05, the angle θ between the slow axis SX of the half-wave plate WP2 and the bilateral privacy protection axis DPAX is 110 degrees (e.g., Figure 4B When the absolute difference between the first refractive index of the first spacer SP1 and the first ordinary refractive index of the first liquid crystal molecule LC1 is less than 0.05, the angle θ between the slow axis SX of the half wave plate WP2 and the double-sided privacy protection axis DPAX is 65 degrees (as shown in FIG. Figure 4C shown).

[0089] In addition to arranging the first absorption axis AX1 of the first polarizer POL1 perpendicular to the first alignment direction AD1, the slow axis SX of the half-wave plate WP2 is arranged in the above manner. This further prevents users from perceiving pixel color unevenness caused by light path deflection at the interface between the first spacer SP1 and the first liquid crystal layer LCL1 when viewing the display device 20, thereby improving the visual quality of the display image.

[0090] In this embodiment, in order to further improve the aforementioned pixel color non-uniformity problem caused by the spacer, preferably, the absolute difference between the ordinary ray refractive index and the extraordinary ray refractive index of the second liquid crystal layer LCL2-A can be less than 0.12 (in this embodiment, the absolute difference between the ordinary ray refractive index and the extraordinary ray refractive index of the first liquid crystal layer LCL1 is not limited, for example, it can be greater than 0.12), and the height of the spacer along the stacking direction (for example, direction Z) of the two adjacent substrates is less than 0.12. Figure 3 The height H2) may be greater than 5 μm and less than 10 μm, but is not limited thereto.

[0091] In this embodiment, the privacy protection module 200A further includes a compensation film 253 disposed between the second polarizer POL2 and the second liquid crystal layer LCL2. Specifically, because the second liquid crystal layer LCL2-A of the second electrically controlled viewing angle switcher 220A in this embodiment is driven in TN mode, the out-of-plane retardation (Rth) of the compensation films 252 and 253 is within a range of -50 nm to -300 nm. In this embodiment, the sum of the out-of-plane retardations of the compensation films 252 and 253 is, for example, -200 nm.

[0092] Figure 5is a cross-sectional view of a display device according to a third embodiment of the present invention. Figure 5 , different from Figure 1 The display device 10A of this embodiment is only provided with the first electrically controlled viewing angle switch 210. In other words, the display device 10A omits Figure 1 The second electrically controlled viewing angle switcher 220, the compensation film 252 and the third polarizer POL3 are arranged.

[0093] Since the first electrically controlled viewing angle switch 210 of this embodiment is similar to Figure 1 For detailed description of the first electrically controlled viewing angle switch 210, please refer to the relevant paragraphs of the aforementioned embodiment, which will not be repeated here.

[0094] In summary, in an anti-peeping module and display device according to an embodiment of the present invention, a plurality of first spacers define a storage space for filling the first liquid crystal layer between the first substrate and the second substrate of the first electrically controlled viewing angle switcher. The first refractive index of the first spacer is within the range between the first ordinary light refractive index and the first extraordinary light refractive index of the first liquid crystal layer. Because the configuration relationship between the first absorption axis of the first polarizer and the first alignment direction of the adjacent first alignment layer depends on the difference between the first refractive index of the first spacer and the first ordinary light refractive index or the first extraordinary light refractive index, the light path deflection angle when passing through the interface between the first spacer and the first liquid crystal layer can be effectively reduced. Accordingly, an anti-peeping module and display device according to an embodiment of the present invention have at least one of the following advantages: it can prevent the user from noticing the phenomenon of uneven pixel color when viewing the display device, thereby improving the visual effect of the display image.

[0095] However, what is described above is only a preferred embodiment of the present invention, and it should not be used to limit the scope of implementation of the present invention. That is, all simple equivalent changes and modifications made in accordance with the claims and the content of the invention are still within the scope of the patent of the present invention. In addition, any embodiment or claim of the present invention does not need to achieve all the purposes, advantages or features disclosed by the present invention. In addition, the abstract and title (invention name) 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 the name of the element or to distinguish different embodiments or scopes, and are not used to limit the upper or lower limit on the number of elements.

Claims

1. A privacy protection module, characterized in that: The anti-peeping module includes a first electrically controlled viewing angle switcher, a first polarizer, and a second polarizer, wherein: The first electrically controlled viewing angle switch includes a first substrate and a second substrate, a first alignment layer, a second alignment layer, a first liquid crystal layer, and a plurality of first spacers, wherein: The first substrate and the second substrate are stacked on each other; The first alignment layer is disposed on the first substrate and has a first alignment direction; The second alignment layer is disposed on the second substrate and has a second alignment direction, wherein an angle between the first alignment direction and the second alignment direction is in a range from 165 degrees to 195 degrees; The first liquid crystal layer is disposed between the first alignment layer and the second alignment layer and comprises a plurality of first liquid crystal molecules, each of the plurality of first liquid crystal molecules having a first optical axis, a first extraordinary light refractive index, and a first ordinary light refractive index, wherein the first extraordinary light refractive index is greater than the first ordinary light refractive index; and The plurality of first spacers are disposed between the first substrate and the second substrate, and each spacer has a first refractive index, wherein the first refractive index is greater than the first ordinary light refractive index and less than the first extraordinary light refractive index; The first polarizer is disposed on a side of the first liquid crystal layer where the first alignment layer is disposed, and has a first absorption axis, wherein the axial direction of the first absorption axis is parallel to or perpendicular to the first alignment direction; and The second polarizer is arranged on a side of the first liquid crystal layer where the second alignment layer is arranged, and has a second absorption axis, wherein the axial direction of the second absorption axis is parallel to or perpendicular to the second alignment direction. When the absolute difference between the first refractive index and the first extraordinary light refractive index is less than 0.05, the axial direction of the first absorption axis is perpendicular to the first alignment direction; when the absolute difference between the first refractive index and the first ordinary light refractive index is less than 0.05, the axial direction of the first absorption axis is parallel to the first alignment direction.

2. The anti-peeping module according to claim 1, wherein: The anti-peeping module further includes a second electrically controlled viewing angle switcher and a third polarizer, wherein: The second electrically controlled viewing angle switch is disposed on a side of the second polarizer facing away from the first electrically controlled viewing angle switch, and the second electrically controlled viewing angle switch includes a third substrate and a fourth substrate, a third alignment layer, a fourth alignment layer, a second liquid crystal layer, and a plurality of second spacers, wherein: The third substrate and the fourth substrate are stacked on each other; The third alignment layer is disposed on the third substrate and has a third alignment direction; The fourth alignment layer is disposed on the fourth substrate and has a fourth alignment direction, wherein an angle between the third alignment direction and the fourth alignment direction is in a range from 165 degrees to 195 degrees; The second liquid crystal layer is disposed between the third alignment layer and the fourth alignment layer and comprises a plurality of second liquid crystal molecules, each of the plurality of second liquid crystal molecules having a second optical axis, a second extraordinary light refractive index, and a second ordinary light refractive index, wherein the second extraordinary light refractive index is greater than the second ordinary light refractive index; and The plurality of second spacers are disposed between the third substrate and the fourth substrate, and each of the second spacers has a second refractive index, wherein the second refractive index is greater than the second ordinary light refractive index and less than the second extraordinary light refractive index; and The third polarizer is arranged on a side of the second electrically controlled viewing angle switch facing away from the first electrically controlled viewing angle switch and has a third absorption axis, which is parallel to or perpendicular to the fourth alignment direction. When the absolute difference between the second refractive index and the second extraordinary light refractive index is less than 0.05, the axial direction of the second absorption axis is perpendicular to the third alignment direction; when the absolute difference between the second refractive index and the second ordinary light refractive index is less than 0.05, the axial direction of the second absorption axis is parallel to the third alignment direction.

3. The anti-peeping module according to claim 2, wherein: The first electrically controlled viewing angle switcher and the second electrically controlled viewing angle switcher each have a double-sided anti-peeping axis, the first alignment direction and the fourth alignment direction are perpendicular to the double-sided anti-peeping axis, and the second alignment direction is parallel to the third alignment direction.

4. The anti-peeping module according to claim 2, wherein: The anti-peeping module further includes a first compensation film and a second compensation film, wherein: The first compensation film is disposed between the first polarizer and the first liquid crystal layer; and The second compensation film is disposed between the third polarizer and the second liquid crystal layer, wherein the out-of-plane phase retardation of each of the first compensation film and the second compensation film is in a range of 100 nm to 500 nm.

5. The anti-peeping module according to claim 1, wherein: The anti-peeping module further includes a second electrically controlled viewing angle switcher and a third polarizer, wherein: The second electrically controlled viewing angle switch is arranged on a side of the second polarizer facing away from the first electrically controlled viewing angle switch, and the second electrically controlled viewing angle switch includes a third substrate and a fourth substrate, a third alignment layer, a fourth alignment layer, and a second liquid crystal layer, wherein: The third substrate and the fourth substrate are stacked on each other; The third alignment layer is disposed on the third substrate and has a third alignment direction; The fourth alignment layer is disposed on the fourth substrate and has a fourth alignment direction, wherein the third alignment direction is perpendicular to the fourth alignment direction; and The second liquid crystal layer is disposed between the third alignment layer and the fourth alignment layer; and The third polarizer is arranged on a side of the second electrically controlled viewing angle switch facing away from the first electrically controlled viewing angle switch and has a third absorption axis, which is parallel to or perpendicular to the fourth alignment direction.

6. The anti-peeping module according to claim 5, characterized in that: The first electrically-controlled viewing angle switcher has a double-sided anti-peeping axis, the second electrically-controlled viewing angle switcher has a single-sided anti-peeping direction, the single-sided anti-peeping direction is parallel to the double-sided anti-peeping axis, the first orientation direction is perpendicular to the double-sided anti-peeping axis, and the angles between the third orientation direction and the fourth orientation direction and the single-sided anti-peeping direction are in the range of 40 degrees to 50 degrees or 130 degrees to 140 degrees.

7. The anti-peeping module according to claim 6, characterized in that: The second absorption axis of the second polarizer is perpendicular to the third absorption axis of the third polarizer, and an angle between the second absorption axis and the third absorption axis and the single-sided privacy protection direction is in the range of 40 degrees to 50 degrees or 130 degrees to 140 degrees.

8. The anti-peeping module according to claim 6, wherein: The anti-peeping module further includes a half-wave plate, wherein: The half-wave plate is arranged between the first electrically-controlled angle of view switcher and the second electrically-controlled angle of view switcher, wherein when the absolute difference between the first refractive index and the first extraordinary light refractive index is less than 0.05, the angle between the slow axis of the half-wave plate and the double-sided anti-peeping axis is 110 degrees, and when the absolute difference between the first refractive index and the first ordinary light refractive index is less than 0.05, the angle between the slow axis of the half-wave plate and the double-sided anti-peeping axis is 65 degrees.

9. The anti-peeping module according to claim 5, characterized in that: The anti-peeping module further includes a first compensation film and a second compensation film, wherein: The first compensation film is disposed between the second polarizer and the second liquid crystal layer; and The second compensation film is disposed between the third polarizer and the second liquid crystal layer, wherein the out-of-plane phase retardation of each of the first compensation film and the second compensation film is within a range of -50 nm to -300 nm.

10. The anti-peeping module according to claim 1, wherein: A difference between the first extraordinary light refractive index and the first ordinary light refractive index is less than 0.12, and a height of each of the plurality of first spacers along a stacking direction of the first substrate and the second substrate is greater than 5 μm and less than 10 μm.

11. A display device, characterized in that: The display device includes a self-luminous display panel and an anti-peeping module, wherein: The anti-peeping module is arranged on one side of the display surface of the self-luminous display panel and includes a first electrically controlled viewing angle switcher, a first polarizer, and a second polarizer, wherein: The first electrically controlled viewing angle switch includes a first substrate and a second substrate, a first alignment layer, a second alignment layer, a first liquid crystal layer, and a plurality of first spacers, wherein: The first substrate and the second substrate are stacked on each other; The first alignment layer is disposed on the first substrate and has a first alignment direction; The second alignment layer is disposed on the second substrate and has a second alignment direction, wherein an angle between the first alignment direction and the second alignment direction is in a range from 165 degrees to 195 degrees; The first liquid crystal layer is disposed between the first alignment layer and the second alignment layer and comprises a plurality of first liquid crystal molecules, each of the plurality of first liquid crystal molecules having a first optical axis, a first extraordinary light refractive index, and a first ordinary light refractive index, wherein the first extraordinary light refractive index is greater than the first ordinary light refractive index; and The plurality of first spacers are disposed between the first substrate and the second substrate, and each spacer has a first refractive index, wherein the first refractive index is greater than the first ordinary light refractive index and less than the first extraordinary light refractive index; The first polarizer is disposed on a side of the first liquid crystal layer where the first alignment layer is disposed, and has a first absorption axis, wherein the axial direction of the first absorption axis is parallel to or perpendicular to the first alignment direction; and The second polarizer is arranged on a side of the first liquid crystal layer where the second alignment layer is arranged, and has a second absorption axis, wherein the axial direction of the second absorption axis is parallel to or perpendicular to the second alignment direction. When the absolute difference between the first refractive index and the first extraordinary light refractive index is less than 0.05, the axial direction of the first absorption axis is perpendicular to the first alignment direction; when the absolute difference between the first refractive index and the first ordinary light refractive index is less than 0.05, the axial direction of the first absorption axis is parallel to the first alignment direction.

12. The display device according to claim 11, wherein The first electrically controlled viewing angle switch further includes a first electrode layer and a second electrode layer, wherein: The first electrode layer and the second electrode layer are respectively arranged on the first substrate and the second substrate, and are used to drive the multiple first liquid crystal molecules of the first liquid crystal layer to rotate, so that the display device switches between a sharing mode and an anti-peeping mode. When there is a first voltage between the first electrode layer and the second electrode layer, the display device operates in the anti-peeping mode. When there is a second voltage between the first electrode layer and the second electrode layer, the display device operates in the sharing mode, and the second voltage is higher than the first voltage.

13. The display device according to claim 11, wherein The display device further comprises a quarter wave plate, wherein: The quarter-wave plate is disposed between the self-luminous display panel and the first polarizer, and an angle between an optical axis of the quarter-wave plate and the first absorption axis of the first polarizer is 45 degrees.

14. The display device according to claim 11, wherein The anti-peeping module further includes a second electrically controlled viewing angle switcher and a third polarizer, wherein: The second electrically controlled viewing angle switch is disposed on a side of the second polarizer facing away from the first electrically controlled viewing angle switch, and the second electrically controlled viewing angle switch includes a third substrate and a fourth substrate, a third alignment layer, a fourth alignment layer, a second liquid crystal layer, and a plurality of second spacers, wherein: The third substrate and the fourth substrate are stacked on each other; The third alignment layer is disposed on the third substrate and has a third alignment direction; The fourth alignment layer is disposed on the fourth substrate and has a fourth alignment direction, wherein an angle between the third alignment direction and the fourth alignment direction is in a range from 165 degrees to 195 degrees; The second liquid crystal layer is disposed between the third alignment layer and the fourth alignment layer and comprises a plurality of second liquid crystal molecules, each of the plurality of second liquid crystal molecules having a second optical axis, a second extraordinary light refractive index, and a second ordinary light refractive index, wherein the second extraordinary light refractive index is greater than the second ordinary light refractive index; and The plurality of second spacers are disposed between the third substrate and the fourth substrate, and each of the second spacers has a second refractive index, wherein the second refractive index is greater than the second ordinary light refractive index and less than the second extraordinary light refractive index; and The third polarizer is arranged on a side of the second electrically controlled viewing angle switch facing away from the first electrically controlled viewing angle switch and has a third absorption axis, which is parallel to or perpendicular to the fourth alignment direction. When the absolute difference between the second refractive index and the second extraordinary light refractive index is less than 0.05, the axial direction of the second absorption axis is perpendicular to the third alignment direction; when the absolute difference between the second refractive index and the second ordinary light refractive index is less than 0.05, the axial direction of the second absorption axis is parallel to the third alignment direction.

15. The display device according to claim 11, wherein The anti-peeping module further includes a second electrically controlled viewing angle switcher and a third polarizer, wherein: The second electrically controlled viewing angle switch is arranged on a side of the second polarizer facing away from the first electrically controlled viewing angle switch, and the second electrically controlled viewing angle switch includes a third substrate and a fourth substrate, a third alignment layer, a fourth alignment layer, and a second liquid crystal layer, wherein: The third substrate and the fourth substrate are stacked on each other; The third alignment layer is disposed on the third substrate and has a third alignment direction; The fourth alignment layer is disposed on the fourth substrate and has a fourth alignment direction, wherein the third alignment direction is perpendicular to the fourth alignment direction; and The second liquid crystal layer is disposed between the third alignment layer and the fourth alignment layer; and The third polarizer is arranged on a side of the second electrically controlled viewing angle switch facing away from the first electrically controlled viewing angle switch and has a third absorption axis, which is parallel to or perpendicular to the fourth alignment direction.

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