Liquid crystal display panel and liquid crystal display
By setting a shielding structure and electrodes in the liquid crystal layer, the display defects caused by the movement of liquid crystal molecules are solved, thereby improving the brightness and viewing angle of the liquid crystal display.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2026-04-07
AI Technical Summary
The problem of poor display quality is caused by the movement of liquid crystal molecules in an upright state during transportation or storage.
Multiple first shielding structures are set in the liquid crystal layer to divide it into multiple sub-regions, and electrodes are set on the shielding structures. The position of liquid crystal molecules is adjusted by controlling the electric field intensity. Combined with the second shielding structure, the liquid crystal molecules are isolated, thereby expanding the viewing angle.
It effectively solves the display problems caused by the movement of liquid crystal molecules, improves the brightness and picture quality of the monitor, avoids the influence of external light mixing, and expands the viewing angle.
Smart Images
Figure CN224096099U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of liquid crystal displays, and in particular to a liquid crystal display panel and a liquid crystal display. Background Technology
[0002] Most LCD display devices on the market are backlit LCDs, which consist of an LCD panel and a backlight module. The working principle of an LCD panel is to place liquid crystal molecules between two parallel glass substrates. Electrodes are set on the glass substrates, and the direction of the liquid crystal molecules is controlled by whether the electrodes are energized or not, so as to refract the light from the backlight module to produce an image.
[0003] Because liquid crystal molecules are intermediate substances between solids and liquids, they exhibit the fluidity of liquids and the anisotropy of solids. When a liquid crystal display panel is transported or stored in an upright position for an extended period, the liquid crystal molecules may shift to one side, resulting in poor display quality. Utility Model Content
[0004] In view of the above-mentioned defects of the prior art, this utility model proposes a liquid crystal display panel and a liquid crystal display, which can solve the problem of poor display caused by the movement of liquid crystal molecules.
[0005] To achieve the above objectives and their purpose, this utility model proposes a liquid crystal display panel, comprising:
[0006] Color film substrate;
[0007] An array substrate is disposed opposite to the color filter substrate;
[0008] A liquid crystal layer is disposed between the color filter substrate and the array substrate;
[0009] A plurality of first shielding structures are disposed in the liquid crystal layer, one end of each first shielding structure being connected to one surface of the liquid crystal layer, and the other end of each first shielding structure extending along the thickness direction of the liquid crystal layer to another surface of the liquid crystal layer, thereby dividing the liquid crystal layer into a plurality of sub-regions; and
[0010] Electrodes extend from the array substrate to the first shielding structure.
[0011] In one embodiment of the present invention, the sidewall of the first shielding structure is perpendicular to the liquid crystal layer.
[0012] In one embodiment of the present invention, the orthographic projection of the first blocking structure on the color filter substrate is located within the black matrix.
[0013] In one embodiment of the present invention, the first blocking structure blocks light rays incident from the maximum incident angle of two adjacent color filters.
[0014] In one embodiment of the present invention, the electrode includes a first electrode and a second electrode, the first electrode and the second electrode are disposed on both sides of the first shielding structure, and the first electrode and the second electrode are disposed on both sides of the sub-region.
[0015] In one embodiment of the present invention, one end of the electrode is connected to the array substrate, and the other end of the electrode extends along the sidewall of the first shielding structure toward the color filter substrate, and the electrode covers the entire sidewall of the first shielding structure.
[0016] In one embodiment of the present invention, the liquid crystal display panel further includes a second shielding structure, one end of which is connected to a surface of the liquid crystal layer, the other end of which extends along the thickness direction of the liquid crystal layer, and the other end of which has a preset distance from the other surface of the liquid crystal layer.
[0017] In one embodiment of this utility model, the preset spacing is greater than the maximum diameter of the liquid crystal molecules.
[0018] In one embodiment of the present invention, the orthographic projection of the second blocking structure on the color filter substrate is located within the black matrix.
[0019] This utility model also provides a liquid crystal display, including:
[0020] The backlight module includes multiple light sources;
[0021] A liquid crystal display is disposed at a position relative to the backlight module, wherein the liquid crystal display includes:
[0022] Color film substrate;
[0023] An array substrate is disposed opposite to the color filter substrate;
[0024] A liquid crystal layer is disposed between the color filter substrate and the array substrate;
[0025] A plurality of first shielding structures are disposed in the liquid crystal layer, one end of each first shielding structure being connected to one surface of the liquid crystal layer, and the other end of each first shielding structure extending along the thickness direction of the liquid crystal layer to another surface of the liquid crystal layer, thereby dividing the liquid crystal layer into a plurality of sub-regions; and
[0026] Electrodes extend from the array substrate to the first shielding structure.
[0027] In summary, this invention proposes a liquid crystal display panel and a liquid crystal display. The liquid crystal display panel uses a first shielding structure to divide the liquid crystal layer into multiple sub-regions, preventing liquid crystal molecules in the liquid crystal layer from shifting to one side and confining the liquid crystal molecules within each sub-region. A second shielding structure is disposed between the first shielding structures, isolating the liquid crystal molecules while expanding the viewing angle of the liquid crystal display panel. Electrodes connected to the array substrate are disposed on the first and second shielding structures. The electric field strength can be adjusted by controlling the electrodes, and the electrodes disposed on the sidewalls of the first and second shielding structures form a field strength parallel to the liquid crystal surface. When the liquid crystal molecules are disordered, they can be quickly controlled to return to their original positions, thereby solving the problem of poor display caused by liquid crystal molecule movement. Simultaneously, the first and second shielding structures are located at the position of the black matrix, and will not affect the light emission. Furthermore, since the first and second shielding structures are made of non-transparent materials, the light reflectivity can be reduced, improving the brightness of the liquid crystal display. Moreover, the first shielding structure can block light incident from the maximum incident angle of two adjacent color filters, thereby avoiding light mixing caused by external light. Therefore, the liquid crystal display panel and liquid crystal display provided in this application can not only solve the problem of poor display caused by the movement of liquid crystal molecules, but also improve the picture quality of the liquid crystal display. Attached Figure Description
[0028] Figure 1 : A schematic diagram of the structure of a liquid crystal display panel in this utility model.
[0029] Figure 2 : A schematic diagram of another type of liquid crystal display panel in this utility model.
[0030] Figure 3 : A schematic diagram of the structure of a liquid crystal display in this utility model. Detailed Implementation
[0031] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model.
[0032] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of this utility model. Therefore, the drawings only show the components related to this utility model and are not drawn according to the actual number, shape and size of the components. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.
[0033] With the widespread adoption of the internet, people are not only inseparable from mobile phones, but e-books, computers, televisions, shop window displays, and advertising machines have also become an integral part of their lives. To a certain extent, the "Internet Age" is the "Display Age." And the display is the medium connecting to the internet. Among them, flat panel display devices such as liquid crystal displays (LCDs) are widely used in various consumer electronics products and have become the mainstream display devices due to their advantages such as high image quality, energy saving, thin body, and wide range of applications.
[0034] Please see Figure 3 As shown, in one embodiment of this utility model, a liquid crystal display (LCD) is provided. The LCD includes a backlight module 200 and a liquid crystal display panel 100, with the liquid crystal display panel 100 disposed on the light-emitting side of the backlight module 200. The liquid crystal display panel 100 does not emit light, and the backlight module 200 provides a light source for the liquid crystal display panel 100 to achieve brightness display.
[0035] Please see Figure 1 As shown, in one embodiment of this utility model, the liquid crystal display panel 100 includes a color filter substrate 110 and an array substrate 130 disposed opposite to each other, and a liquid crystal layer 120 disposed between the color filter substrate 110 and the array substrate 130. The liquid crystal layer 120 contains liquid crystal molecules 125, and the brightness of the liquid crystal display panel 100 is adjusted by controlling the flipping of the liquid crystal molecules 125.
[0036] Please see Figure 1 As shown, in one embodiment of this utility model, the color filter substrate 110 includes a first substrate 111 and a color filter layer 112. The color filter layer 112 is disposed on the first substrate 111 and is bonded to the liquid crystal layer 120. The first substrate 111 is a transparent substrate, and its material is, for example, glass, polymethyl methacrylate, polycarbonate, polyethylene, polypropylene, polyethylene terephthalate, or polyimide. The first substrate 111 provides support for the color filter layer 112 without obstructing the light source.
[0037] Please see Figure 1 As shown, in one embodiment of this invention, the color filter layer 112 includes multiple color filters and a black matrix 1124. The black matrix 1124 is disposed on the first substrate 111 and located between adjacent color filters to prevent light leakage between them. The material of the black matrix 1124 is, for example, a photosensitive resin composition. To form the black matrix 1124, the photosensitive resin composition is first coated onto the first substrate 111, and then the black matrix 1124 is formed by exposure and development.
[0038] Please see Figure 1 As shown, in one embodiment of this utility model, the color filter includes a red filter 1121, a green filter 1122, and a blue filter 1123, which are arranged alternately. The red filter 1121 allows only red light to pass through, separating red light. The green filter 1122 allows only green light to pass through, separating green light. The blue filter 1123 allows only blue light to pass through, separating blue light. By using the red filter 1121, green filter 1122, and blue filter 1123 to separate the three primary colors of light, a color image can be displayed. The position of one filter forms a sub-pixel, and the three filters of different colors arranged alternately form a complete pixel.
[0039] Please see Figure 1 As shown, in one embodiment of this utility model, a red filter 1121 and a green filter 1122 cover a black matrix 1124 and the first substrates 111 on both sides thereof. The green filter 1122 and a blue filter 1123 cover another black matrix 1124 and the first substrates 111 on both sides thereof. The blue filter 1123 and another red filter 1121 cover yet another black matrix 1124 and the first substrates 111 on both sides thereof. In this application, the thickness of the black matrix 1124 is less than the thickness of the color filters, and two adjacent color filters completely cover the black matrix 1124 between the two color filters.
[0040] Please see Figure 1 As shown, in one embodiment of this utility model, the array substrate 130 includes a second substrate 131 and a driving circuit layer 132. The driving circuit layer 132 is disposed on the second substrate 131 and is attached to the liquid crystal layer 120, i.e., the driving circuit layer 132 is located between the second substrate 131 and the liquid crystal layer 120. The circuits in the driving circuit layer 132 can be centrally arranged, and the orthogonal projection of the circuits in the driving circuit layer 132 onto the color filter substrate 110 is covered by the black matrix 1124, preventing the circuits in the driving circuit layer 132 from affecting light transmission.
[0041] Please see Figure 1 As shown, in one embodiment of this utility model, a liquid crystal layer 120 is disposed between a color filter substrate 110 and an array substrate 130. The liquid crystal layer 120 is filled with liquid crystal molecules 125, which are arranged sequentially within the liquid crystal layer 120.
[0042] Please see Figure 1As shown, in one embodiment of this utility model, to improve display quality, a plurality of first blocking structures 121 are provided in the liquid crystal layer 120. The plurality of first blocking structures 121 are arranged side-by-side in the liquid crystal layer 120. One end of each first blocking structure 121 is connected to one surface of the liquid crystal layer 120, and the other end of each first blocking structure 121 extends along the thickness direction of the liquid crystal layer 120 to another surface of the liquid crystal layer 120, dividing the liquid crystal layer 120 into multiple sub-regions. That is, the plurality of first blocking structures 121 are arranged parallel to the thickness direction of the liquid crystal layer 120. In this way, the liquid crystal in each sub-region will only move within that sub-region, avoiding display problems caused by liquid crystal flowing to one side when the liquid crystal display panel 100 is in one state for a long time.
[0043] Please see Figure 1 As shown, in one embodiment of this utility model, the first blocking structure 121 is made of a light-shielding material. Specifically, the material of the first blocking structure 121 is, for example, the same as the material of the black matrix 1124, and is made of a black photoresist layer. The reflectivity of the black photoresist layer ranges from 4.5 to 4.7, and the optical density of the black photoresist layer is from 3.2 to 3.4. Therefore, when the first blocking structure 121 distinguishes the liquid crystal molecules 125, due to the low reflectivity of the first blocking structure 121, the reflection of light is reduced, which can improve the display brightness of the display and thus improve the display quality.
[0044] Please see Figure 1 As shown, in one embodiment of this invention, the sidewall of the first blocking structure 121 is disposed perpendicular to the liquid crystal layer 120. Furthermore, the orthographic projection of the first blocking structure 121 onto the color filter substrate 110 is located within the black matrix 1124, thus preventing the first blocking structure 121 from blocking the light transmitted through the color filter. Additionally, the centerline of the first blocking structure 121 coincides with the centerline of the black matrix 1124.
[0045] Please see Figure 1 As shown, in one embodiment of this utility model, the first blocking structure 121 blocks light rays incident from the maximum incident angle of two adjacent color filters. In this case, the first blocking structure 121 can also prevent the external incident light from the two adjacent color filters from affecting the display effect, avoiding light mixing and causing display blurring.
[0046] Please see Figure 1As shown, in one embodiment of this utility model, electrodes are provided on the sidewall of the first blocking structure 121, and the electrodes include a first electrode 123 and a second electrode 124, which are arranged opposite to each other. That is, the first electrode 123 and the second electrode 124 are respectively provided on both sides of the first blocking structure, and the first electrode 123 and the second electrode 124 are respectively provided on both sides of a sub-region of a liquid crystal layer 120. One end of the first electrode 123 and the second electrode 124 is connected to the array substrate 130, and the other end extends along the sidewall of the first blocking structure 121 toward the color filter substrate 110, and the first electrode 123 and the second electrode 124 cover part or all of the sidewall of the first blocking structure 121. The first electrode 123 and the second electrode 124 are connected to the driving circuit layer 132 on the array substrate 130. Through the control of the circuit in the driving circuit layer 132, the first electrode 123 and the second electrode 124 can be adjusted, thereby adjusting the electric field between them. Since the electric field formed between the first electrode 123 and the second electrode 124 is parallel to the plane containing the sub-regions of the liquid crystal layer 120, adjusting the electric field between the first electrode 123 and the second electrode 124 can enhance the regulation of the liquid crystal molecules 125 in each sub-region, thereby increasing the movement efficiency of the liquid crystal molecules 125. When the liquid crystal molecules 125 in each sub-region of the liquid crystal layer 120 are disordered, adjusting the first electrode 123 and the second electrode 124 can restore the liquid crystal molecules 125 in each sub-region to an ordered state.
[0047] Please see Figure 1 As shown, in one embodiment of the present invention, in order to ensure that the electric field of the liquid crystal molecules 125 in each sub-region of the liquid crystal layer 120 is uniform, one end of the first electrode 123 and the second electrode 124 are connected to the array substrate 130, and the other end extends along the sidewall of the first shielding structure 121 toward the color filter substrate 110, and the electrode covers the entire sidewall of the first shielding structure 121.
[0048] Please see Figure 1 As shown, in one embodiment of this utility model, the spacing between adjacent first occlusion structures 121 is set according to actual needs. In some embodiments, a black matrix 1124 is provided between adjacent first occlusion structures 121. In other embodiments, two or more black matrices 1124 are provided between adjacent first occlusion structures 121.
[0049] Please see Figure 2As shown, in another embodiment of this utility model, when one, two, or more black matrices 1124 are provided between adjacent first occlusion structures 121, a second occlusion structure 122 can also be provided between adjacent first occlusion structures 121. Multiple second occlusion structures 122 are arranged side-by-side, and one, two, or more second occlusion structures 122 can be provided between adjacent first occlusion structures 121, specifically depending on the spacing between adjacent first occlusion structures 121 and the number of black matrices 1124.
[0050] Please see Figure 2 As shown, in another embodiment of this utility model, one end of each second shielding structure 122 is connected to one surface of the liquid crystal layer 120, and the other end of each second shielding structure 122 extends along the thickness direction of the liquid crystal layer 120, with a preset distance between the other end of the second shielding structure 122 and the other surface of the liquid crystal layer 120. The preset distance between the other end of the second shielding structure 122 and the other surface of the liquid crystal layer 120 is greater than the maximum diameter of the liquid crystal molecules 125, allowing the liquid crystal molecules 125 to pass through the gap between the second shielding structure 122 and the surface of the liquid crystal layer 120. In this case, the second shielding structure 122 can isolate the sub-regions in the liquid crystal layer 120, and the liquid crystal molecules 125 can move on both sides of adjacent second shielding structures 122 under the action of electrodes, thereby expanding the viewing angle of the liquid crystal display panel 100.
[0051] Please see Figure 2 As shown, in another embodiment of this invention, the second shading structure 122 is made of a light-shielding material. Specifically, the material of the second shading structure 122 is, for example, the same as the material of the black matrix 1124, and is made of a black photoresist layer.
[0052] Please see Figure 2 As shown, in another embodiment of this utility model, the center line and sidewalls of the second blocking structure 122 are perpendicular to the liquid crystal layer 120, and the orthographic projection of the second blocking structure 122 on the color filter substrate 110 is located in the black matrix 1124, which can prevent the second blocking structure 122 from blocking the light transmitted through the color filter. Furthermore, the center line of the second blocking structure 122 coincides with the center line of the black matrix 1124.
[0053] Please see Figure 2As shown, in another embodiment of this utility model, electrodes are provided on the sidewall of the second blocking structure 122, and the electrodes include a first electrode 123 and a second electrode 124, which are arranged opposite to each other. That is, the first electrode 123 and the second electrode 124 are respectively provided on both sides of the second blocking structure, and the first electrode 123 on the second blocking structure is adjacent to the second electrode 124 on the first or second blocking structure, and the second electrode 124 on the second blocking structure is adjacent to the first electrode 123 on the first or second blocking structure. On the second blocking structure, one end of the first electrode 123 and the second electrode 124 are connected to the array substrate 130, and the other end extends along the sidewall of the second blocking structure 122 toward the color filter substrate 110, and the electrodes cover part or all of the sidewall of the second blocking structure 122. The first electrode 123 and the second electrode 124 on the second shielding structure 122 are connected to the driving circuit layer 132 on the array substrate 130. Through the control of the circuit in the driving circuit layer 132, the first electrode 123 and the second electrode 124 can be adjusted, thereby adjusting the electric field between them. Since the electric field formed between the first electrode 123 and the second electrode 124 is parallel to the plane containing the sub-regions of the liquid crystal layer 120, adjusting the electric field between the first electrode 123 and the second electrode 124 can enhance the regulation of the liquid crystal molecules 125 in each sub-region, thereby increasing the movement efficiency of the liquid crystal molecules 125. When the liquid crystal molecules 125 in each sub-region of the liquid crystal layer 120 are disordered, adjusting the first electrode 123 and the second electrode 124 can restore the liquid crystal molecules 125 in each sub-region to an ordered state.
[0054] Please see Figure 2 As shown, in another embodiment of the present invention, in order to ensure that the electric field of the liquid crystal molecules 125 in each sub-region of the liquid crystal layer 120 is uniform, one end of the first electrode 123 and the second electrode 124 are connected to the array substrate 130, and the other end extends along the sidewall of the second shielding structure 122 toward the color filter substrate 110, and the electrode covers the entire sidewall of the second shielding structure 122.
[0055] Please see Figure 3As shown, in one embodiment of this utility model, the backlight module 200 includes a back plate 201, a light source 202, a diffuser plate 203, a quantum dot film 204, and an optical film 205. Specifically, the light source 202 is disposed on the back plate 201, and the diffuser plate 203, quantum dot film 204, and optical film 205 are disposed on the back plate 201 and cover the light source 202. The light emitted by the light source 202 passes sequentially through the diffuser plate 203, the quantum dot film 204, and the optical film 205 to reach the liquid crystal display panel 100. The diffuser plate 203 is used to optically diffuse the blue light emitted by the light source 202 to make the light more uniform. Because the quantum dot film 204 has weak intensity, the diffuser plate 203 also supports the quantum dot film 204. The quantum dot film 204 is used to excite the colored quantum dot particles within it when blue light passes through, thereby converting it into white light, which serves as the backlight source required for the display product. The optical film 205 is used to diffuse and brighten light to obtain uniform and bright light. The optical film 205 is composed of a diffuser, a brightening film, and a composite film. Different combinations of one or more different films can achieve different brightness gains.
[0056] In summary, this utility model proposes a liquid crystal display panel and a liquid crystal display. The liquid crystal display panel includes a color filter substrate and an array substrate disposed opposite each other, with a liquid crystal layer disposed between the color filter substrate and the array substrate. Multiple first blocking structures are disposed in the liquid crystal layer to divide the liquid crystal layer into multiple sub-regions, preventing display defects caused by liquid crystal molecule movement. Simultaneously, multiple second blocking structures are disposed in the liquid crystal layer to isolate liquid crystal molecules and expand the viewing angle of the liquid crystal display panel. Electrodes are disposed on the sidewalls of the first and second blocking structures to control the rapid repositioning of liquid crystal molecules in the sub-regions of the liquid crystal layer, thereby solving the problem of display defects caused by liquid crystal molecule movement.
[0057] The above description is only a preferred embodiment of this application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the utility model involved in this application is not limited to the technical solutions formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the concept of the utility model. For example, technical solutions formed by replacing the above features with technical features with similar functions disclosed in this application (but not limited to) each other.
[0058] Apart from the technical features described in the specification, the other technical features are known to those skilled in the art. To highlight the innovative features of this utility model, the other technical features will not be described in detail here.
Claims
1. A liquid crystal display panel, characterized in that, include: Color film substrate; An array substrate is disposed opposite to the color filter substrate; A liquid crystal layer is disposed between the color filter substrate and the array substrate; Multiple first shielding structures are disposed in the liquid crystal layer. One end of the first shielding structure is connected to one surface of the liquid crystal layer, and the other end of the first shielding structure extends along the thickness direction of the liquid crystal layer to another surface of the liquid crystal layer, thereby dividing the liquid crystal layer into multiple sub-regions. as well as An electrode extends from the array substrate to the first shielding structure. The electrode includes a first electrode and a second electrode. The first electrode and the second electrode are disposed on both sides of the first shielding structure, and the first electrode and the second electrode are disposed on both sides of the sub-region.
2. The liquid crystal display panel according to claim 1, characterized in that, The sidewall of the first shielding structure is perpendicular to the liquid crystal layer.
3. The liquid crystal display panel according to claim 1, characterized in that, The orthographic projection of the first occlusion structure onto the color filter substrate is located within the black matrix.
4. The liquid crystal display panel according to claim 1, characterized in that, The first blocking structure blocks light rays incident from the maximum incident angle of the two adjacent color filters.
5. The liquid crystal display panel according to claim 1, characterized in that, One end of the electrode is connected to the array substrate, and the other end of the electrode extends along the sidewall of the first shielding structure toward the color filter substrate, and the electrode covers the entire sidewall of the first shielding structure.
6. The liquid crystal display panel according to claim 1, characterized in that, The liquid crystal display panel further includes a second shielding structure, one end of which is connected to one surface of the liquid crystal layer, the other end of which extends along the thickness direction of the liquid crystal layer, and the other end of which has a preset distance from the other surface of the liquid crystal layer.
7. The liquid crystal display panel according to claim 6, characterized in that, The preset spacing is greater than the maximum diameter of the liquid crystal molecules.
8. The liquid crystal display panel according to claim 6, characterized in that, The orthographic projection of the second occlusion structure onto the color filter substrate is located within the black matrix.
9. A liquid crystal display, characterized in that, include: The backlight module includes multiple light sources; A liquid crystal display is disposed at a position relative to the backlight module, wherein the liquid crystal display includes: Color film substrate; An array substrate is disposed opposite to the color filter substrate; A liquid crystal layer is disposed between the color filter substrate and the array substrate; A plurality of first shielding structures are disposed in the liquid crystal layer, one end of each first shielding structure being connected to one surface of the liquid crystal layer, and the other end of each first shielding structure extending along the thickness direction of the liquid crystal layer to another surface of the liquid crystal layer, thereby dividing the liquid crystal layer into a plurality of sub-regions; and An electrode extends from the array substrate to the first shielding structure. The electrode includes a first electrode and a second electrode. The first electrode and the second electrode are disposed on both sides of the first shielding structure, and the first electrode and the second electrode are disposed on both sides of the sub-region.