Viewing angle adjusting panel and display device comprising same

Abstract

The viewing angle adjusting panel comprises an organic film provided with a plurality of opening parts, and a liquid crystal layer located in the opening parts; the liquid crystal layer includes liquid crystal molecules and a dye, and the liquid crystal molecules and the dye are oriented in a predetermined direction to adjust a viewing angle of light transmitted through the liquid crystal layer.

Description

Technical Field

[0001] The present disclosure relates to a display device, and more particularly, to a viewing angle adjustment panel and a display device including the same. Background Art

[0002] As the information society develops, the demand for display devices for displaying images has increased in various forms. For example, display devices are used in various electronic devices such as smartphones, digital cameras, notebook computers, navigation, and smart TVs.

[0003] The display device can be applied to a car dashboard, a center fascia, or a center information display (CID) of an instrument panel. This display device can use viewing angle technology to ensure the viewing angle, but as needed, a film that limits the light emission angle is used for safety or to improve reflection. However, in the process of limiting the light emission angle of the display panel, the aperture ratio of the display panel is reduced, resulting in a decrease in brightness. Summary of the invention

[0004] An object of the present invention is to provide a viewing angle adjustment panel capable of minimizing brightness reduction and adjusting viewing angle, and a display device including the same.

[0005] The viewing angle adjustment panel of one embodiment includes: an organic film having a plurality of openings; a liquid crystal layer located in the openings. The liquid crystal layer includes liquid crystal molecules and dyes, and the liquid crystal molecules and the dyes are oriented in a predetermined direction to adjust the viewing angle of light passing through the liquid crystal layer.

[0006] The viewing angle adjustment panel may further include a first electrode and a second electrode that apply an electric field to the liquid crystal layer.

[0007] The first electrode may be located on one side wall of the opening, and the second electrode may be located on the other side wall of the opening.

[0008] The first electrode may be located on a lower surface of the liquid crystal layer, and the second electrode may be located on an upper surface of the liquid crystal layer.

[0009] The liquid crystal layers located in the plurality of openings may be connected as a whole on the upper surfaces of the openings.

[0010] A part of the plurality of openings may be filled with a light shielding member.

[0011] The liquid crystal layer may further include reactive mesogens.

[0012] The reactive mesogen may include a compound represented by the following Chemical Formula 1,

[0013] [Chemical formula 1]

[0014]

[0015] A display device of an embodiment includes: a display panel; and a viewing angle adjustment panel located at a position overlapping the display panel. The display panel includes: a substrate; and a plurality of light-emitting elements located on the substrate. The viewing angle adjustment panel includes: an organic film having a plurality of openings; and a liquid crystal layer located in the openings. The liquid crystal layer includes liquid crystal molecules and a dye, and the liquid crystal molecules and the dye are oriented in a predetermined direction to adjust the viewing angle of light emitted from the light-emitting element.

[0016] Some of the plurality of openings may be located at positions overlapping with the light emitting element.

[0017] The display device may further include a partition wall located between the plurality of light emitting elements, and a portion of the plurality of openings may be located at a position overlapping with the partition wall.

[0018] The opening portion overlapping the partition wall may be filled with a light shielding member.

[0019] The display device may further include a first electrode and a second electrode that apply an electric field to the liquid crystal layer.

[0020] The first electrode may be located on one side wall of the opening, and the second electrode may be located on the other side wall of the opening.

[0021] The first electrode may be located on a lower surface of the liquid crystal layer, and the second electrode may be located on an upper surface of the liquid crystal layer.

[0022] The liquid crystal layers located in the plurality of openings may be connected as a whole on the upper surfaces of the openings.

[0023] The liquid crystal layer may further include reactive mesogens.

[0024] The reactive mesogen may include a compound represented by the following Chemical Formula 1,

[0025] [Chemical formula 1]

[0026]

[0027] The display device may switch between a light shielding mode and a light transmitting mode according to voltages applied to the first electrode and the second electrode.

[0028] The display device may adjust front brightness and side brightness according to voltages applied to the first electrode and the second electrode.

[0029] (Effects of the Invention)

[0030] According to an embodiment, a viewing angle adjustment panel capable of minimizing a decrease in brightness and adjusting a viewing angle and a display device including the same are provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a cross-sectional view schematically showing the cross section of the display device of this embodiment.

[0032] Figure 2 FIG. 5 is a diagram showing the principle of light shielding and light transmission when an electric field is applied to a liquid crystal layer including a dye.

[0033] Figure 3 This is a diagram schematically showing the absorbance corresponding to the angle θ between the incident light and the dye arrangement axis.

[0034] Figure 4 Another embodiment is shown in Figure 1 Same cross-section diagram.

[0035] Figure 5 Another embodiment is shown in Figure 1 Same cross-section diagram.

[0036] Figure 6 and Figure 7 It is enlarged to show Figure 5 Figure in part A.

[0037] Figure 8 Another embodiment is shown in Figure 5 Same cross-section diagram.

[0038] Fig. 9 Another embodiment is shown in Figure 6 Figure 1.2 of the same region.

[0039] Fig.10 Another embodiment is shown in Figure 6 Figure 1.2 of the same region.

[0040] Fig.11 Another embodiment is shown in Figure 1 Same cross-section diagram. DETAILED DESCRIPTION

[0041] Hereinafter, in order to enable those skilled in the art to easily implement the present invention, multiple embodiments of the present invention are described in detail with reference to the accompanying drawings. The present invention can be implemented in various different ways and is not limited to the embodiments described here.

[0042] In order to clearly explain the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

[0043] In addition, since the size and thickness of each structure shown in the drawings are arbitrarily shown for the convenience of explanation, the present invention is not limited to the drawings shown. In order to clearly show multiple layers and regions, the thickness is enlarged in the drawings. In addition, in the drawings, for the convenience of explanation, the thickness of some layers and regions is exaggerated.

[0044] In addition, when a layer, film, region, plate or other part is mentioned as being "on" or "above" another part, it includes not only the case where it is "directly" "on" another part, but also the case where there is another part in between. Conversely, when a part is mentioned as being "directly" another part, it means that there is no other part in between. In addition, being "on" or "above" a part that serves as a reference means being above or below the part that serves as a reference, and does not necessarily mean being "on" or "above" the side opposite to the direction of gravity.

[0045] Furthermore, throughout the specification, when it is mentioned that a certain part “includes” a certain constituent element, unless there is a special description to the contrary, it means that other constituent elements may also be included, rather than excluding other constituent elements.

[0046] In addition, throughout the specification, “in plan view” refers to a state when an object portion is viewed from above, and “in cross section” refers to a state when a cross section of an object portion cut vertically is viewed from the side.

[0047] Hereinafter, a display device according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0048] Figure 1 2 is a cross-sectional view schematically showing a cross-section of a display device of this embodiment. Figure 1 The display device of this embodiment includes a display panel DP and a viewing angle adjustment panel 300. Figure 1 , the display panel DP is briefly shown as including: a substrate SUB; a partition wall 350, located on the substrate SUB; light emitting elements LED, respectively located in the openings of the partition wall 350; and a packaging layer TFE, located on the partition wall 350 and the light emitting elements LED; The packaging layer TFE may be a multi-layer stacked structure including a first layer TFE1, a second layer TFE2, and a third layer TFE3, but is not limited thereto. In one embodiment, the first layer TFE1 and the third layer TFE3 may be inorganic films, and the second layer TFE2 may be an organic film.

[0049] Although Figure 1Although not shown in the figure, each light emitting element LED may include a first electrode connected to each transistor located on the substrate SUB, and the first electrode, the light emitting layer, and the second electrode may constitute the light emitting element LED. The main feature of the present invention is the structure of the viewing angle adjustment panel 300, so the display panel DP is not limited to a specific shape, and the following description is centered on the structure of the viewing angle adjustment panel 300. That is, the use of the display panel DP in the display device of this embodiment is not limited.

[0050] Reference Figure 1 The viewing angle adjustment panel 300 of this embodiment includes an organic film 310 having a plurality of openings and a liquid crystal layer 320 filling the openings. A cover glass 400 may be provided on the viewing angle adjustment panel 300 .

[0051] like Figure 1 As shown, a liquid crystal layer 320 is provided in the space between each organic film 310. At this time, the liquid crystal layer 320 may include liquid crystal molecules 330 and dyes 340. The organic film 310 may be transparent. The liquid crystal layer 320 includes dyes, which can shield the light incident on the display panel DP. The display device of this embodiment can adjust the brightness of the side or upper and lower surfaces by the viewing angle adjustment panel 300 having the liquid crystal layer 320 including the liquid crystal molecules 330 and the dyes 340, and does not reduce the brightness of the front surface, which will be described separately below. In addition, by applying a suitable electric field to the liquid crystal layer 320, the brightness can be appropriately controlled according to the viewing angle according to the use environment.

[0052] The display device may be required to protect privacy or block the brightness of the upper, lower, left and right sides in the use environment. As an example, for a display screen for a car windshield, a separate display screen can be set for the passenger in the front passenger seat who does not need to look forward. However, the light generated from the display in all directions will be reflected by the glass window at night, which may hinder the viewer in the front passenger seat and may also hinder the driver's field of vision. In addition, in an environment where privacy protection is required, it may be required to use a display that can only be viewed by the person in the front, and the picture cannot be seen from the side or upper and lower surfaces. In this regard, the display device of this embodiment is characterized in that the brightness of the side or upper and lower surfaces is reduced by the viewing angle adjustment panel 300, but the brightness of the front surface is not reduced. Therefore, privacy can be protected and the display can be applied to various use environments.

[0053] Generally, the viewing angle adjustment panel 300 includes an organic film 310 having a plurality of openings and a light shielding member filling the openings of the organic film 310. However, if the light shielding member is included in this manner, there is a problem that the transmittance and brightness of the front surface are reduced due to the light shielding member. That is, since the light shielding member is located in the area overlapping with the light emitting element, it blocks the light emitted to the front surface, resulting in a reduction in luminous efficiency.

[0054] However, in the display device of this embodiment, the viewing angle adjustment panel 300 includes liquid crystal molecules and dyes. Although the orientation of the liquid crystal molecules and the dyes blocks light in a specified direction, it also transmits light in other directions, so that the side brightness or the brightness in the up and down directions can be reduced, but the front surface brightness will not be reduced. In addition, when an electric field is applied to the liquid crystal layer 320, it can be appropriately adjusted to a light shielding mode or a light transmission mode according to the use environment.

[0055] Reference Figure 1 , the width D1 of the opening of the organic film 310 overlapping the light emitting element LED may be 1 μm to 10 μm. More specifically, the width D1 of the opening of the organic film 310 may be 3 μm to 5 μm. In addition, the depth D2 of the opening of the organic film 310 may be 15 μm to 25 μm. However, the width D1 and the depth D2 of the opening of the organic film 310 may be appropriately changed according to the embodiment.

[0056] The liquid crystal molecules included in the liquid crystal layer 320 may be nematic liquid crystal or cholesteric liquid crystal. When the liquid crystal layer includes cholesteric liquid crystal, it can absorb light in all polarization directions. The liquid crystal molecules may use either negative liquid crystal or positive liquid crystal.

[0057] Figure 2 3 is a diagram illustrating the principle of light shielding and light transmission when an electric field is applied to a liquid crystal layer including a dye. Figure 2 Negative liquid crystal and dye are shown in FIG. Figure 2 , when the liquid crystal molecules and the dye are arranged parallel to the traveling direction of the light, almost no light is absorbed. However, when the liquid crystal molecules and the dye are arranged perpendicular to the traveling direction of the light, the light is absorbed by the dye. Therefore, when the liquid crystal layer 320 including the liquid crystal molecules and the dye is used as a partition wall of the viewing angle adjustment panel 300, light can be effectively blocked. In addition, light blocking and light transmission can be appropriately adjusted by applying an electric field.

[0058] Figure 3 This is a diagram schematically showing the absorbance corresponding to the angle θ between the incident light and the dye arrangement axis. Figure 3 The absorbance was measured by changing the angle θ between the incident light and the dye arrangement axis, and the absorbance is shown in the following Table 1.

[0059] [Table 1]

[0060]

[0061]

[0062] With reference to Table 1, it can be confirmed that the larger the angle, the higher the absorption rate based on the dye, and good shading is achieved. In addition, it can be confirmed that the smaller the angle, the lower the absorption rate. When the viewing angle adjustment panel 300 includes a shading component that replaces the liquid crystal layer, there may be a problem that the brightness drops sharply at a specific angle. That is, due to the shading component, not only the brightness of the front surface is reduced, but also the brightness drops sharply when the side angle changes, which is not desirable in a specific use environment. However, as can be confirmed in Table 1 above, it is desirable that the brightness gradually decreases when the viewing angle adjustment panel includes a liquid crystal layer as in this embodiment.

[0063] Figure 1 3 shows a case where the liquid crystal layers 320 located in the openings of the organic films 310 are separated from each other, but according to an embodiment, the liquid crystal layers 320 may be connected as one. Figure 4 Another embodiment is shown in Figure 1 Figure of the same section. Figure 4 In addition to the liquid crystal layer 320 being connected as a whole, the display device of this embodiment is Figure 1 Detailed description of the same components will be omitted.

[0064] In addition, the liquid crystal layer 320 of the viewing angle adjustment panel 300 of the display device of the present embodiment may further include a reactive liquid crystal element. That is, the liquid crystal layer 320 of the viewing angle adjustment panel 300 of the present embodiment may further include a reactive liquid crystal element. The liquid crystal layer including such a reactive liquid crystal element may be thinned by a UV curing process. As an example, the reactive liquid crystal element may include a compound shown in the following chemical formula 1, but is not limited thereto.

[0065] [Chemical formula 1]

[0066]

[0067] Figure 5 Another embodiment is shown in Figure 1 Figure of the same section. Figure 5 In addition to further including the first electrode E1 and the second electrode E2, the display device of this embodiment is Figure 1 Detailed description of the same components will be omitted.

[0068] Reference Figure 5 In the display device of this embodiment, the first electrode E1 and the second electrode E2 can be alternately arranged one by one across the openings of the respective organic films 310. A data voltage is applied to the first electrode E1, and a common voltage is applied to the second electrode E2. The orientation state of the liquid crystal layer can be changed according to the voltage applied to the first electrode E1 and the second electrode E2, and the viewing angle adjustment panel can be switched to a light transmission mode or a light shielding mode.

[0069] Figure 6 and Figure 7 It is enlarged to show Figure 5 Figure in part A. Figure 6 and Figure 7 As shown, the alignment state of the liquid crystal layer varies depending on the applied voltage, and the viewing angle adjustment panel can be switched to a light-transmitting mode or a light-shielding mode.

[0070] Figure 5 3 shows a structure in which the first electrodes E1 and the second electrodes E2 are alternately arranged one by one through the openings of the organic film 310 , but the formation positions of the first electrodes E1 and the second electrodes E2 may be in various forms.

[0071] Figure 8 Another embodiment is shown in Figure 5 Figure of the same section. Figure 8 , except for the positions of the first electrode E1 and the second electrode E2, Figure 5 The same embodiment is the same. Detailed description of the same components is omitted. Figure 8 The first electrode E1 and the second electrode E2 may be located on the upper and lower surfaces of the viewing angle adjustment panel 300 and face each other. By applying voltage to the first electrode E1 and the second electrode E2, the alignment direction of the liquid crystal molecules of the liquid crystal layer is determined, so that the light shielding mode and the light transmission mode can be switched.

[0072] Or it can be a mixture Figure 5 and Figure 8 Electrode configuration of the method. Fig. 9 is shown with Figure 6 Figure 1.1 shows the same area. Fig. 9 In the viewing angle adjustment panel of this embodiment, the first electrode E1 and the second electrode E2 are both located on the side and the bottom surface of the opening of the organic film 310. Fig. 9 As shown, the orientation of liquid crystal molecules varies depending on the region, and the refractive index or viewing angle can be adjusted.

[0073] Fig.10 Another embodiment is shown in Figure 6 Figure 1.1 shows the same area. Fig.10In the viewing angle adjustment panel of this embodiment, the first electrode E1 and the second electrode E2 are arranged in an interlaced manner up and down. Therefore, the dye tilts (Tilt) in response to the fringe field (Fringe field) between the first electrode E1 and the second electrode E2, and the side cutoff characteristics can be further improved by adjusting the degree of this tilt. That is, the viewing angle can be accurately adjusted by region, and the viewing angle can be appropriately adjusted according to the use environment. For car displays, the front viewing angle may be different depending on the height of the passenger. In this embodiment, the brightness of the front and side can be appropriately controlled according to the height of the passenger, and the best audio-visual environment can be achieved according to the use environment.

[0074] Although the structure in which all openings of the organic film 310 are filled with the liquid crystal layer 320 is shown above, in another embodiment, a part of the openings of the plurality of organic films 310 may be filled with the light shielding member 360. That is, the present invention includes a configuration in which the light shielding member 360 and the liquid crystal layer 320 are mixed.

[0075] Fig.11 Another embodiment is shown in Figure 1 Figure of the same section. Fig.11 In the viewing angle adjustment panel of the display device of this embodiment, a part of the openings of the plurality of organic films 310 are filled with the light shielding member 360, and another part of the openings are filled with the liquid crystal layer 320. Fig.11 As shown, among the plurality of openings, the openings overlapping with the partition wall 350 of the display panel DP may be filled with the shading member 360, and the openings overlapping with the light emitting element LED may be filled with the liquid crystal layer 320. As described above, when the viewing angle adjustment panel includes the shading member 360, the front brightness may be reduced. However, the portion overlapping with the partition wall 350 is not a light-emitting area, and therefore does not affect the front brightness. Therefore, the shading member 360 may be filled in the portion overlapping with the partition wall 350. Fig.11 As shown, the openings of the plurality of openings that overlap with the light emitting element LED can be filled with a liquid crystal layer including liquid crystal molecules and dyes, thereby preventing the front brightness from decreasing and narrowing or widening the viewing angle according to the use environment.

[0076] The embodiments of the present invention are described in detail above, but the protection scope of the present invention is not limited thereto. Various modifications and improvements implemented by ordinary technicians in this field using the basic concepts of the present invention defined by the claims all fall within the protection scope of the present invention.

Claims

1. A viewing angle adjustment panel, in, include: The organic film has a plurality of openings. a liquid crystal layer, located in the opening; The liquid crystal layer includes liquid crystal molecules and dyes, The liquid crystal molecules and the dye are aligned in a predetermined direction to adjust a viewing angle of light transmitted through the liquid crystal layer.

2. The viewing angle adjustment panel according to claim 1, wherein: Also included are first and second electrodes for applying an electric field to the liquid crystal layer.

3. The viewing angle adjustment panel according to claim 2, wherein: The first electrode is located on a side wall of the opening. The second electrode is located on the other side wall of the opening.

4. The viewing angle adjustment panel according to claim 2, wherein: The first electrode is located on the lower surface of the liquid crystal layer, The second electrode is located on the upper surface of the liquid crystal layer.

5. The viewing angle adjustment panel according to claim 1, wherein: The liquid crystal layers located in the plurality of openings are connected as a whole on the upper surfaces of the openings.

6. The viewing angle adjustment panel according to claim 1, wherein: A part of the plurality of openings is filled with a light shielding member.

7. The viewing angle adjustment panel according to claim 1, wherein: The liquid crystal layer further includes reactive mesogens.

8. The viewing angle adjustment panel according to claim 7, wherein: The reactive mesogen includes a compound represented by the following Chemical Formula 1, [Chemical formula 1] 9. A display device, in, include: Display panel, A viewing angle adjustment panel, located at a position overlapping with the display panel; The display panel comprises: substrate, A plurality of light-emitting elements are located on the substrate; The viewing angle adjustment panel comprises: The organic film has a plurality of openings. a liquid crystal layer, located in the opening; The liquid crystal layer includes liquid crystal molecules and dyes, The liquid crystal molecules and the dye are aligned in a predetermined direction to adjust a viewing angle of light emitted from the light emitting element.

10. The display device according to claim 9, wherein: Some of the plurality of openings are located at positions overlapping with the light emitting element.

11. The display device according to claim 9, wherein: It also includes a partition wall located between the plurality of light emitting elements, Some of the plurality of openings are located at positions overlapping with the partition wall.

12. The display device according to claim 11, wherein: The opening portion overlapping the partition wall is filled with a light shielding member.

13. The display device according to claim 9, wherein: Also included are first and second electrodes for applying an electric field to the liquid crystal layer.

14. The display device according to claim 13, wherein: The first electrode is located on a side wall of the opening. The second electrode is located on the other side wall of the opening.

15. The display device according to claim 13, wherein: The first electrode is located on the lower surface of the liquid crystal layer, The second electrode is located on the upper surface of the liquid crystal layer.

16. The display device according to claim 9, wherein: The liquid crystal layers located in the plurality of openings are connected as a whole on the upper surfaces of the openings.

17. The display device according to claim 9, wherein: The liquid crystal layer further includes reactive mesogens.

18. The display device according to claim 17, wherein: The reactive mesogen includes a compound represented by the following Chemical Formula 1, [Chemical formula 1] 19. The display device according to claim 13, wherein: The display device switches between a light shielding mode and a light transmitting mode according to voltages applied to the first electrode and the second electrode.

20. The display device according to claim 13, wherein: The display device adjusts front brightness and side brightness according to voltages applied to the first electrode and the second electrode.

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