Liquid crystal display element

Abstract

Provided is a liquid crystal display element capable of switching between a transparent state and a scattering state and capable of suppressing a decrease in luminance in the scattering state. The present invention provides a liquid crystal display element including: a liquid crystal panel having a polymer network and a polymer dispersed liquid crystal including a liquid crystal component; and a light source module having a light source located laterally to the liquid crystal panel and a mirror that reflects light irradiated from the light source toward the liquid crystal panel side.

Description

Technical Field

[0001] The following disclosure relates to a liquid crystal display element. Background Technology

[0002] Liquid crystal display (LCD) elements are display elements that utilize liquid crystal compositions for display purposes. A typical display method involves applying a voltage to a liquid crystal composition sealed between a pair of substrates. The applied voltage causes a change in the orientation state of the liquid crystal molecules within the composition, thereby controlling the amount of light transmitted. Such LCD elements are characterized by their thinness, light weight, and low power consumption, and are used in a wide range of fields.

[0003] In addition, in recent years, see-through displays, which can display the back of a liquid crystal display element, have attracted attention. Examples of see-through displays include liquid crystal display elements with a liquid crystal panel containing polymer-dispersed liquid crystal (PDLC). PDLC disperses liquid crystal components within a polymer network; by applying a voltage, the orientation state of the liquid crystal components changes, thereby utilizing the refractive index difference between the liquid crystal components and the polymer network to switch between a transparent state and a scattering state.

[0004] As a technology related to liquid crystal display elements using PDLC, for example, Patent Document 1 discloses a display device comprising: a pair of transparent substrates separated and arranged opposite to each other; a light modulation layer disposed between the pair of transparent substrates, having a predetermined refractive index anisotropy, and having a plurality of light modulation elements having different responsiveness to an electric field generated by electrodes disposed on the transparent substrates; and a light source that incident light of a predetermined color onto the light modulation layer from a side of the light modulation layer, wherein the light modulation layer transmits incident light incident from the light source when no electric field is generated, and scatters the incident light and emits it toward the transparent substrate when the electric field is generated. Existing technical documents Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2016-85452 Summary of the Invention The technical problem to be solved by the present invention

[0006] The inventors have conducted research on a perspective display using PDLC. Figure 18 This is a schematic diagram illustrating a method for measuring the brightness of an LCD panel. Figure 19 This is a graph illustrating an example of the brightness measurement results for a liquid crystal panel using PDLC. (Example:) Figure 18 and Figure 19As shown, in the past, in LCD panels 11R that used PDLC, due to the anisotropic diffusion characteristics of PDLC, there was a problem that the brightness in the viewing direction was lower the further away from the light source.

[0007] As a light source for a transparent display, an edge-light backlight using a light guide plate can be cited as an example. In an edge-light backlight, a light source is positioned on the side of the light guide plate. Light incident from this light source on the side of the light guide plate is repeatedly reflected within the light guide plate and then emitted forward. On the other hand, some of the light reflected by the light guide plate is lost due to diffraction or absorption in the components of the liquid crystal panel, such as thin-film transistors (TFTs) and alignment films. Therefore, the further away from the light source, the greater the light loss, resulting in a decrease in the frontal characteristics of the displayed image, such as contrast and brightness in the center.

[0008] In Patent Document 1, since PDLC is used as the light modulation layer in the liquid crystal panel, there is a problem that the brightness decreases in the viewing direction as the distance from the light source increases. Furthermore, because Patent Document 1 guides light from the edge-light backlight into the PDLC, light loss due to diffraction and scattering caused by the TFTs and polymer-dispersed liquid crystals inside the liquid crystal panel results in significant attenuation of light from the sides as it travels towards the center of the liquid crystal panel, leading to insufficient brightness at the center of the panel.

[0009] As a see-through display, examples can be listed Figure 20 The box-shaped perspective display shown. Figure 20 This is a three-dimensional schematic diagram showing an example of a box-shaped perspective display. Figure 20 The box-shaped transparent display 1RB shown has a field-sequential color (FSC) driven light source and a transmissive liquid crystal panel. More specifically, in the box-shaped transparent display 1RB, an LED light source 21XR with red (R), green (G) and blue (B) LEDs is arranged on the upper part of the box 2R, using light diffused by the wall of the box 2R as the light source, and switching between transmissive and non-transmissive in the liquid crystal panel 11R.

[0010] If a box-type perspective display 1RB is used, a sample can be placed inside a box 2R, and the display of a liquid crystal panel 11R can be overlaid on the sample for the observer to see. However, if the reflected light from the sample inside the box 2R is weak, or if the sample is a specific color, even if the display is overlaid on the sample, high-brightness full-color display is not possible.

[0011] The present invention was made in view of the above-mentioned situation, and its object is to provide a liquid crystal display element that can switch between a transparent state and a scattering state and can suppress the reduction of brightness in the scattering state. Solution to the problem

[0012] (1) One embodiment of the present invention is a liquid crystal display element, comprising: a liquid crystal panel having a polymer network and a polymer-dispersed liquid crystal containing liquid crystal components; and a light source module having a light source and a reflector, wherein the light source is located to the side of the liquid crystal panel and the reflector reflects light irradiated by the light source toward the liquid crystal panel side.

[0013] (2) In addition, in one embodiment of the present invention, based on the configuration described in (1) above, the light source module and one of the two opposite end edge portions of the liquid crystal panel are respectively provided.

[0014] (3) In addition, in one embodiment of the present invention, based on the above (2) configuration, the light source is a first light source, the reflector is a first reflector, the light source module is a first light source module, and the liquid crystal display element further includes a second light source module. The second light source module has a second light source and a second reflector. The second light source is located on the side of the liquid crystal panel and is disposed corresponding to the other end edge portion of the pair of end edge portions. The second reflector reflects the light irradiated by the second light source toward the liquid crystal panel side.

[0015] (4) In addition, in one embodiment of the present invention, based on the above (2) configuration, the light source is a first light source, the reflector is a first reflector, the light source module is a first light source module, and the liquid crystal display element further includes a third light source module. The third light source module has a third reflector but does not have a light source. The third reflector is located on the side of the liquid crystal panel and is disposed corresponding to the other end edge portion of the pair of end edge portions, and reflects the incident light toward the liquid crystal panel side.

[0016] (5) In addition, in one embodiment of the present invention, based on the above (1), (2), (3) or (4), the reflector is an integral freeform surface reflector.

[0017] (6) In addition, in a certain embodiment of the present invention, based on the configuration described in (1), (2), (3), (4) or (5) above, the reflector has a shape represented by two or more independent functions.

[0018] (7) In addition, in a certain embodiment of the present invention, based on the configuration described in (1), (2), (3), (4), (5) or (6) above, the reflector has a shape represented by three or more independent functions.

[0019] (8) Furthermore, in a certain embodiment of the present invention, based on the configurations described in (1), (2), (3), (4), (5), (6), or (7) above, the reflector has a collimating portion for collimating a Lambertian light source, a first light distribution portion, and a second light distribution portion. When the thickness direction of the liquid crystal panel is taken as the x-axis direction, the horizontal direction within the surface of the liquid crystal panel is taken as the y-axis direction, and the vertical direction within the surface of the liquid crystal panel is taken as the z-axis direction, the collimating portion is disposed away from the liquid crystal panel in the z-axis direction. A light distribution section is disposed further away from the liquid crystal panel in the x-axis direction than the collimating section, and a second light distribution section is disposed further away from the liquid crystal panel in the x-axis direction than the first light distribution section. More than 30% and less than 60% of the collimated total light beam illuminates the first light distribution section, of which more than 40% and less than 100% illuminates the liquid crystal panel. Furthermore, more than 40% and less than 70% of the collimated total light beam that does not illuminate the first light distribution section illuminates the second light distribution section, of which more than 40% and less than 100% illuminates the liquid crystal panel.

[0020] (9) Furthermore, in a certain embodiment of the present invention, based on the configurations described in (1), (2), (3), (4), (5), (6), or (7) above, the reflector has a collimating portion for collimating a Lambertian light source, a first light distribution portion, and a second light distribution portion. When the thickness direction of the liquid crystal panel is taken as the x-axis direction, the horizontal direction within the surface of the liquid crystal panel is taken as the y-axis direction, and the vertical direction within the surface of the liquid crystal panel is taken as the z-axis direction, the collimating portion is disposed away from the liquid crystal panel in the z-axis direction. The two light distribution sections are arranged further away from the liquid crystal panel in the x-axis direction than the collimating section, and the first light distribution section is arranged further away from the liquid crystal panel in the x-axis direction than the second light distribution section. More than 30% and less than 60% of the collimated total light beam illuminates the second light distribution section, of which more than 40% and less than 100% illuminates the liquid crystal panel. Furthermore, more than 40% and less than 70% of the collimated total light beam that does not illuminate the second light distribution section illuminates the first light distribution section, of which more than 40% and less than 100% illuminates the liquid crystal panel.

[0021] (10) In addition, in a certain embodiment of the present invention, based on the configuration described in (8) or (9) above, the amount of light irradiated from the first light distribution unit to the liquid crystal panel is at its maximum value within a range of 60% from the edge portion of the liquid crystal panel on the side where the light source module is disposed, and the amount of light irradiated from the second light distribution unit to the liquid crystal panel is at its maximum value within a range of 50% from the edge portion of the liquid crystal panel opposite to the edge portion on the side where the light source module is disposed.

[0022] (11) In addition, in a certain embodiment of the present invention, based on the configurations described in (1), (2), (3), (4), (5), (6), (7), (8), (9), or (10) above, the reflector has a collimating portion for collimating the light source of the Lambertian emission, a first light distribution portion, and a second light distribution portion. If the thickness direction of the liquid crystal panel is set as the x-axis direction, the horizontal direction in the plane of the liquid crystal panel is set as the y-axis direction, and the vertical direction in the plane of the liquid crystal panel is set as the z-axis direction... Let the length of the liquid crystal panel along the z-axis be A [mm], the point of the light source module that is closest to the liquid crystal panel be the module relative coordinate (x, z) = (0, 0), and the unit of the module relative coordinate be mm. Then the module relative coordinate (x1, z1), the module relative coordinate (x2, z2), the module relative coordinate (x3, z3) of the first light distribution part, and the module relative coordinate (x4, z4) of the second light distribution part satisfy the following (Equation 1) to (Equation 15): (x1, z1) = (x e ,0)…(Equation 1) z2=(4×x e ×x2) 0.5 …(Equation 2) z3=-(4×a×x3) 0.5 +(b×x3)+α…(Equation 3) z4 = -(4 × c × x4) 0.5 +(d×x4)+β…(Equation 4) 1×(A / 300)≦x e ≦30×(A / 300)…(Equation 5) 0≦x1≦60×(A / 300)…(Equation 6) 30×(A / 300)≦x2≦80×(A / 300)…(Formula 7) 45×(A / 300)≦x3≦90×(A / 300)…(Formula 8) 55×(A / 300)≦x4≦90×(A / 300)…(Formula 9) 0≦a≦50…(Equation 10) -10≦b≦10…(Equation 11) 0≦c≦50…(Equation 12) -10≦d≦10…(Equation 13) 0×(A / 300)≦α≦100×(A / 300)…(Formula 14) 0×(A / 300)≦β≦100×(A / 300)…(Equation 15).

[0023] (12) In addition, in one embodiment of the present invention, based on the configuration described in (11) above, the reflector further includes a third light distribution section, wherein the module relative coordinates (x5, z5) of the third light distribution section satisfy the following (Equation 16) to (Equation 19): z5 = -(4 × e × x5) 0.5 +(f×x5)+γ…(Equation 16) 0≦e≦50…(Equation 17) -10≦f≦10…(Equation 18) 0×(A / 300)≦γ≦100×(A / 300)…(Equation 19).

[0024] (13) In addition, in a certain embodiment of the present invention, based on the configuration described in (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11), or (12) above, when the thickness direction of the liquid crystal panel is set as the x-axis direction, the horizontal direction in the plane of the liquid crystal panel is set as the y-axis direction, the vertical direction in the plane of the liquid crystal panel is set as the z-axis direction, and the point of the light source module that is closest to the liquid crystal panel is set as the module relative coordinate (x, z) = (0, 0), the light source module has a diffuser plate on the plane of z = 0, and the diffuser plate has a haze of 1% or more and 40% or less.

[0025] (14) In addition, in one embodiment of the present invention, based on the configuration of (13), the diffuser plate is disposed on the back side of the liquid crystal panel. Invention Effects

[0026] According to the present invention, a liquid crystal display element capable of switching between a transparent state and a scattering state and capable of suppressing the reduction of brightness in the scattering state can be provided. Attached Figure Description

[0027] Figure 1 This is a three-dimensional schematic diagram of the liquid crystal display element according to Embodiment 1. Figure 2This is a schematic diagram illustrating the light emitted from the light source module of the liquid crystal display element in Embodiment 1. Figure 3 This is a cross-sectional schematic diagram illustrating the transparent state of the liquid crystal panel of the liquid crystal display element in Embodiment 1. Figure 4 This is a cross-sectional schematic diagram illustrating the scattering state of the liquid crystal panel of the liquid crystal display element in Embodiment 1. Figure 5 This is a block diagram showing the overall configuration of the liquid crystal display element according to Embodiment 1. Figure 6 This is a diagram showing the configuration of a single frame in the liquid crystal display element according to Embodiment 1. Figure 7 This is a diagram showing an example of the configuration coordinates of a mirror in a liquid crystal display element according to Embodiment 1, where the mirror has a shape represented by two or more independent functions. Figure 8 This is a perspective view showing an example of the light source module included in the liquid crystal display element of Embodiment 1. Figure 9 This is a three-dimensional schematic diagram of the liquid crystal display element according to Embodiment 2. Figure 10 This is a three-dimensional schematic diagram of the liquid crystal display element according to embodiment 3. Figure 11 This is a cross-sectional schematic diagram of the liquid crystal display element of Comparative Example 1. Figure 12 This is a cross-sectional schematic diagram of the liquid crystal display element in Embodiment 1. Figure 13 This is a schematic diagram illustrating a method for measuring the front scattering of the liquid crystal panel of the liquid crystal display element of Embodiment 1. Figure 14 This is a graph showing the measurement results of the front scattering of the liquid crystal panel of the liquid crystal display element of Embodiment 1. Figure 15 This is a top view schematic diagram of the light source of the light source module of the liquid crystal display element in Embodiment 1. Figure 16 This is a diagram showing the configuration coordinates of the liquid crystal panel and the light source module of the liquid crystal display element in Embodiment 1. Figure 17 This is a front view diagram illustrating the upper, central, and lower parts of the screen of a liquid crystal display element. Figure 18 This is a schematic diagram illustrating a method for measuring the brightness of an LCD panel. Figure 19This is a graph showing an example of the measurement results of the brightness of a liquid crystal panel using PDLC. Figure 20 This is a three-dimensional schematic diagram showing an example of a box-shaped perspective display. Detailed Implementation

[0028] Although the invention is described in more detail below with reference to the accompanying drawings, the invention is not limited to these embodiments.

[0029] (Definition of the term) In this manual, the term "viewing side" refers to the side closer to the screen (display surface) of the LCD panel, and the term "back side" refers to the side farther from the screen (display surface) of the LCD panel.

[0030] (Implementation Method 1) Figure 1 This is a three-dimensional schematic diagram of the liquid crystal display element according to Embodiment 1. Figure 2 This is a schematic diagram illustrating the light emitted from the light source module of the liquid crystal display element in Embodiment 1. Figure 3 This is a cross-sectional schematic diagram illustrating the transparent state of the liquid crystal panel of the liquid crystal display element in Embodiment 1. Figure 4 This is a cross-sectional schematic diagram illustrating the scattering state of the liquid crystal panel of the liquid crystal display element in Embodiment 1.

[0031] like Figures 1 to 4 As shown, the liquid crystal display element 1 of this embodiment includes a liquid crystal panel 11, which has a polymer-dispersed liquid crystal 300 comprising a polymer network 310 and a liquid crystal component 320. By employing this method, it is possible to switch between a transparent state and a scattering state. Furthermore, image display is possible without using a polarizing plate, and the reduction in transmittance in the transparent state can be suppressed.

[0032] The liquid crystal display element 1 of this embodiment includes a light source module 20, which has a light source 21 located on the side of the liquid crystal panel 11 and a reflector 22 that reflects light irradiated from the light source 21 toward the liquid crystal panel 11. Specifically, in Figure 1In this embodiment, when viewing the display surface of the rectangular liquid crystal panel 11 along the x-axis (from the viewing surface side towards the back side), the light source 21 is positioned to the side of the liquid crystal panel 11 along the y-axis (the direction of the long side of the liquid crystal panel 11). By employing this method, the illuminance of the area far from the light source 21 can be improved by utilizing the light distribution of the reflector 22, thereby suppressing the increase in power consumption and suppressing the decrease in brightness in the scattered state of the area far from the light source module 20 within the surface of the liquid crystal panel 11. As a result, the uniformity of the brightness distribution within the surface can be improved. For example, the decrease in brightness in the center of the screen can be suppressed. Thus, in the liquid crystal display element 1 of this embodiment, by using the light source module 20, the illuminance of the light illuminating the surface of the liquid crystal panel 11 can be optimized.

[0033] In the display device of Patent Document 1, a backlight equipped with a light guide plate and a light source illuminates the transparent panel. On the other hand, the liquid crystal display element 1 of this embodiment does not use a light guide plate, and the light source module 20 differs from that of Patent Document 1 in that it includes a light source 21 and a reflector 22. Furthermore, in the liquid crystal display element 1 of this embodiment, the illuminance in the area with a larger projection angle, i.e., the area farther from the light source 21, is improved by the light distribution of the reflector 22. Therefore, in this embodiment, while maintaining a thin profile and high transmittance, the in-plane brightness uniformity is improved compared to Patent Document 1 with low power consumption, thereby enabling the realization of a high-brightness transparent display.

[0034] In the box-type perspective display 1RB, as described above, an LED light source 21XR is arranged at the top of the box 2R. The light diffusely reflected from the wall of the box 2R is used as the light source, and the liquid crystal panel 11R switches between transmission and non-transmission modes. On the other hand, in this embodiment, a liquid crystal panel 11 capable of switching between scattering and transmission states is used. If the polymer-dispersed liquid crystal 300 of the liquid crystal panel 11 is in a voltage-applied state, causing light incident from the light source 21 onto the liquid crystal panel 11 to be scattered, the light exits towards the front (the observer's visual recognition area). If the polymer-dispersed liquid crystal 300 is in a voltage-unapplied state, causing light incident from the light source 21 onto the liquid crystal panel 11 to be transmitted, the light enters an area that is not visually recognizable by the observer. Thus, the configuration of the box-type perspective display described above differs from that of the liquid crystal display element 1 in this embodiment.

[0035] In the cassette-type perspective display 1RB, the wall surface is preferably white. On the other hand, the liquid crystal display element 1 of this embodiment can be used even without utilizing the reflection of light from the wall surface, so the wall surface may not be required. When the liquid crystal display element 1 of this embodiment is used in a cassette-type perspective display, color inversion may occur if the intensity of the reflected light from the wall surface is higher than the scattered light from the polymer-dispersed liquid crystal, so the color of the wall surface is preferably black.

[0036] Furthermore, a polarizer is necessary in the box-type transparent display 1RB, resulting in a transmittance of approximately 20%. On the other hand, the liquid crystal display element 1 of this embodiment does not require a polarizing plate, thus enabling the achievement of high transmittance (e.g., 60%).

[0037] Furthermore, as described above, when the reflected light from the sample inside the cell 2R is weak, or when the sample is a specific color, the cassette-type perspective display 1RB cannot achieve high-brightness full-color display even when overlaid on the sample. On the other hand, the liquid crystal display element 1 of this embodiment is independent of the sample's color and can overlay color display across the entire surface of the sample. Hereinafter, this embodiment will be described in detail.

[0038] like Figure 3 and Figure 4 As shown, the liquid crystal panel 11 includes a first substrate 100, a polymer-dispersed liquid crystal 300, and a second substrate 200 sequentially from the back side to the viewing side. The first substrate 100 includes a first support substrate 110 and a pixel electrode 120. The second substrate 200 includes a second support substrate 210 and a common electrode 220.

[0039] The liquid crystal panel 11 preferably includes a thin film transistor (TFT). Light irradiated from the light source module 20 can be attenuated due to diffraction or scattering by the TFTs within the liquid crystal panel. However, in the liquid crystal display element 1 of this embodiment, the light source module 20, which includes a light source 21 and a reflector 22 located to the side of the liquid crystal panel 11, irradiates the liquid crystal panel 11 through an air layer 30. That is, an air layer 30 exists between the light emitting surface and the light incident surface of the liquid crystal panel 11. Therefore, even when the liquid crystal panel 11 includes TFTs, the aforementioned light attenuation caused by the TFTs can be suppressed, and the reduction in brightness of the central portion of the panel under scattering conditions can be effectively suppressed. On the other hand, in conventional liquid crystal panels, a light guide plate containing acrylic resin or the like is disposed between the light emitting surface and the light incident surface of the liquid crystal panel, resulting in a structure different from this embodiment. The following description will explain how the liquid crystal panel 11 (specifically, the first substrate 100) includes TFTs, but is not limited to this.

[0040] The first substrate 100 is a substrate provided with TFTs, which are switching elements used to switch the pixels of the liquid crystal panel 11 on / off. In this embodiment, the configuration of the first substrate 100 for TN mode will be described.

[0041] The first substrate 100, from the back side to the viewing side, sequentially comprises: a first support substrate 110; a plurality of gate lines extending parallel to each other; a gate insulating film; a plurality of source lines extending parallel to each other in the direction intersecting with each gate line; an interlayer insulating film; and a pixel electrode 120. The plurality of gate lines and the plurality of source lines are integrally formed in a grid pattern to divide each pixel. A TFT serving as a switching element is disposed at the intersection of each gate line and each source line. A pixel electrode 120 is disposed in each region surrounded by two adjacent gate lines and two adjacent source lines.

[0042] Each TFT is connected to a corresponding gate line and source line among multiple gate lines and multiple source lines, and is a three-terminal switch. This three-terminal switch has: a gate electrode protruding from the corresponding gate line (as part of the gate line); a source electrode protruding from the corresponding source line (as part of the source line); a drain electrode connected to a corresponding pixel electrode among multiple pixel electrodes; and a thin-film semiconductor layer. The source and drain electrodes are electrodes disposed on the same source wiring layer as the source line, and the gate electrode is an electrode disposed on the same gate wiring layer as the gate line.

[0043] Each TFT's thin-film semiconductor layer is composed of, for example, a high-resistance semiconductor layer and a low-resistance semiconductor layer. The high-resistance semiconductor layer is composed of amorphous silicon, polycrystalline silicon, etc., and the low-resistance semiconductor layer is composed of n+ amorphous silicon doped with impurities such as phosphorus. Alternatively, oxide semiconductor layers such as zinc oxide can also be used as thin-film semiconductor layers. Examples of oxide semiconductor layers include In-Ga-Zn-O (indium gallium zinc oxide), which is composed primarily of indium (In), gallium (Ga), zinc (Zn), and oxygen (O). By employing such an In-Ga-Zn-O-TFT, in addition to achieving high precision and low power consumption, the write speed can also be improved compared to the past. Furthermore, the same effect can be obtained when using an oxide semiconductor layer containing at least one of indium, gallium, zinc, copper (Cu), silicon (Si), tin (Sn), aluminum (Al), calcium (Ca), germanium (Ge), and lead (Pb).

[0044] The first support substrate 110 and the second support substrate 210 are preferably transparent substrates, such as glass substrates and plastic substrates.

[0045] The gate insulating film is, for example, an inorganic insulating film. As an inorganic insulating film, inorganic films such as silicon nitride (SiNx) and silicon oxide (SiO2) (relative permittivity ε = 5 to 7) and their laminates can be used.

[0046] The gate wiring layer and source wiring layer are, for example, single or multiple layers of metals such as copper, titanium, aluminum, molybdenum, tungsten, or their alloys. Gate lines, source lines, and various wirings and electrodes constituting a TFT can be formed by depositing single or multiple layers of metals such as copper, titanium, aluminum, molybdenum, tungsten, or their alloys using sputtering or similar methods, followed by patterning using photolithography or similar methods. Since these various wirings and electrodes are formed on the same layer, the use of the same materials for each layer improves manufacturing efficiency.

[0047] Interlayer insulating films are, for example, inorganic insulating films. As inorganic insulating films, such as silicon nitride (SiNx), silicon oxide (SiO2), etc. (relative permittivity ε = 5 to 7), and their laminates can be used.

[0048] Pixel electrodes 120 are electrodes arranged in a planar (full-surface) manner in each region surrounded by two adjacent gate lines and two adjacent source lines. Pixel electrodes 120 are electrically connected to their corresponding source lines via a thin-film semiconductor layer of the TFT. Pixel electrodes 120 are set to a potential corresponding to a data signal supplied via the corresponding TFT.

[0049] The common electrode 220 is an electrode formed almost on one surface, independent of the pixel boundary. A common signal is supplied to the common electrode 220 and maintained at a fixed value, thus maintaining the common electrode 220 at a fixed potential.

[0050] Materials used for the pixel electrode 120 and the common electrode 220 include, for example, indium tin oxide (ITO) and indium zinc oxide (IZO).

[0051] The polymer-dispersed liquid crystal 300 has a polymer network 310 and a liquid crystal component 320, and is sandwiched between a first substrate 100 and a second substrate 200. In the polymer-dispersed liquid crystal 300, the fibrous matrix of the cured photopolymerizable liquid crystal compound aggregates to form a three-dimensional continuous polymer network 310, resulting in a phase-separated state of the liquid crystal component 320 within the polymer network 310.

[0052] The polymer-dispersed liquid crystal 300 comprises a polymer network 310 composed of a cured product of a photopolymerizable liquid crystal compound and a liquid crystal component 320. It is transparent when no voltage is applied and scattering when a voltage is applied. By employing this method, a display element that does not require a polarizing plate can be realized. More specifically, it is transparent when no voltage is applied, and when a voltage is applied, the orientation of the liquid crystal component 320 changes, resulting in a scattering state.

[0053] Here, "no voltage applied" refers to the moment when the voltage applied to the polymer-dispersed liquid crystal 300 is less than the threshold voltage (including when no voltage is applied), and "voltage applied" refers to the moment when the voltage applied to the polymer-dispersed liquid crystal 300 is greater than or equal to the threshold voltage. "No voltage applied" is also called the voltage-unapplied state, and "voltage applied" is also called the voltage-applied state.

[0054] The following uses Figure 3 and Figure 4 This illustrates the orientation state of liquid crystal component 320 in both transparent and scattering states. Figure 3 and Figure 4 This indicates the central portion of the LCD panel 11.

[0055] like Figure 3 As shown, preferably, when no voltage is applied, the orientation of the polymer network 310 and the liquid crystal component 320 is approximately equal. Figure 3 The example illustrates a case where both the polymer network 310 and the liquid crystal component 320 are homogeneously oriented relative to the main surfaces of the first substrate 100 and the second substrate 200. When no voltage is applied, there is almost no refractive index difference (ne) between the liquid crystal component 320 and the polymer network 310, nor is there a refractive index difference (no) between the ordinary light refractive index (no) between the liquid crystal component 320 and the polymer network 310, in all directions including the thickness direction of the polymer-dispersed liquid crystal 300. Therefore, light irradiated from the light source module 20 passes through the polymer-dispersed liquid crystal 300, resulting in a transparent state. Furthermore, the state where there is almost no refractive index difference (ne) between the liquid crystal component 320 and the polymer network 310, nor is there a refractive index match between the liquid crystal component 320 and the polymer network 310, can also be described as a state where the refractive indices of the liquid crystal component 320 and the polymer network 310 are matched, in all directions including the thickness direction of the polymer-dispersed liquid crystal 300.

[0056] A transparent state refers to a state in which the liquid crystal is transparent to light. For example, the transmittance of the polymer-dispersed liquid crystal 300 in a transparent state can be 80% or more, or 90% or more. Furthermore, the upper limit of the transmittance of the polymer-dispersed liquid crystal 300 in a transparent state is, for example, 100%. In this embodiment, the polymer-dispersed liquid crystal 300 in a transparent state is transparent to visible light. In this specification, the transmittance of the polymer-dispersed liquid crystal in a transparent state refers to the transmittance of parallel light rays from the polymer-dispersed liquid crystal in a transparent state. The transmittance of the polymer-dispersed liquid crystal in a transparent state can be obtained, for example, as follows: Using a luminance meter (SR-UL1) manufactured by Topcon, the luminance is measured at a light reception angle of 2° when a liquid crystal panel with the polymer-dispersed liquid crystal is placed on a conventional backlight (light source for liquid crystal display elements) with a halogen lamp as the light source, in a state where no voltage is applied, and when no backlight is placed on the aforementioned backlight. The measurement wavelength is set to the highest wavelength of the visual reflectance Y value, which represents the visual sensitivity of the human eye, approximately 550 nm. The transmittance of the transparent polymer-dispersed liquid crystal can be determined by dividing the brightness of the liquid crystal panel in the state where no voltage is applied on the backlight by the brightness when no backlight is applied.

[0057] like Figure 4 As shown, when a voltage is applied, the polymer network 310 maintains a horizontal orientation relative to the main surfaces of the first substrate 100 and the second substrate 200, while the liquid crystal component 320 is oriented in the vertical direction. When a voltage is applied, the orientation potential of the liquid crystal component 320 changes due to the electric field formed in the polymer-dispersed liquid crystal 300, while the polymer network 310 is unaffected by the electric field. Therefore, in all directions including the thickness direction of the polymer-dispersed liquid crystal 300, the refractive index difference of the anomalous refractive index ne between the liquid crystal component 320 and the polymer network 310, and the refractive index difference of the ordinary refractive index no between the liquid crystal component 320 and the polymer network 310, increase. When unpolarized light from the light source module 20 is incident on the polymer-dispersed liquid crystal 300 from an oblique angle, unlike the case where unpolarized light is incident perpendicularly to the polymer-dispersed liquid crystal 300, it is scattered independently of polarized light, thus the polymer-dispersed liquid crystal 300 becomes in a strongly scattered state. Furthermore, in all directions including the thickness direction of the polymer-dispersed liquid crystal 300, the large refractive index difference of the abnormal light refractive index ne between the liquid crystal component 320 and the polymer network 310, and the large refractive index difference of the normal light refractive index no between the liquid crystal component 320 and the polymer network 310, can also be described as a state of refractive index mismatch between the liquid crystal component 320 and the polymer network 310.

[0058] The scattering state refers to a state in which light is scattered. For example, the transmittance of the polymer-dispersed liquid crystal 300 in the scattering state can be, for example, 50% or less. Furthermore, the lower limit of the transmittance of the polymer-dispersed liquid crystal 300 in the scattering state is, for example, 0 to 1%. In this specification, the transmittance of the polymer-dispersed liquid crystal in the scattering state refers to the transmittance of parallel light rays from the polymer-dispersed liquid crystal in the scattering state. The transmittance of the polymer-dispersed liquid crystal in the scattering state can be obtained, for example, as follows: Using a luminance meter (SR-UL1) manufactured by Topcon, the luminance is measured at a light reception angle of 2° when a liquid crystal panel with a voltage applied state containing the polymer-dispersed liquid crystal is disposed on a conventional backlight (light source for liquid crystal display elements) equipped with a halogen lamp as a light source, and the luminance is measured when no backlight is disposed. The measurement wavelength is set to the highest wavelength of the visual reflectance Y value, which represents the visual sensitivity of the human eye, approximately 550 nm. By dividing the luminance when the liquid crystal panel is disposed on the backlight in the voltage applied state by the luminance when no backlight is disposed, the transmittance of the polymer-dispersed liquid crystal in the scattering state can be determined.

[0059] Furthermore, the haze, which represents the light scattering rate of the polymer-dispersed liquid crystal 300 in the scattering state, varies depending on the applied voltage, and can be, for example, 80% or more, or 90% or more. Additionally, the upper limit of the haze, representing the light scattering rate of the polymer-dispersed liquid crystal 300 in the scattering state, is, for example, 90 to 100%. In this embodiment, the polymer-dispersed liquid crystal 300 in the scattering state scatters visible light. Therefore, the polymer-dispersed liquid crystal 300 in the scattering state is in the same state as frosted glass. In this specification, the haze is measured using a method based on JIS K7136. The aforementioned haze can be measured, for example, using a halogen lamp as the light source, such as a turbidimeter "HazeMeter NDH2000" manufactured by Nippon Denshoku Kogyo Co., Ltd.

[0060] In this way, the liquid crystal display element 1 adjusts the amount of light transmitted through the liquid crystal panel 11 by changing the refractive index difference of ne and no between the liquid crystal component 320 and the polymer network 310 in the polymer dispersed liquid crystal 300, thus eliminating the need for a polarizing plate required by conventional liquid crystal display elements.

[0061] As a photopolymerizable liquid crystal compound used to form the polymer network 310, for example, it presents a liquid crystal phase at room temperature and is compatible with the liquid crystal component 320, and when it is cured by ultraviolet irradiation to form a polymer, it separates from the liquid crystal component 320 phase.

[0062] Examples of photopolymerizable liquid crystal compounds include monomers having substituents such as biphenyl, terphenyl, naphthyl, phenylbenzoate, azophenyl, and their derivatives (hereinafter also referred to as mesocrystalline groups), cinnamyl, chalcone, cinnamyl, β-(2-phenyl)acryloyl, cinnamic acid, and their derivatives, as well as polymerizable groups such as acrylates, methacrylates, maleimides, N-phenylmaleimides, and siloxanes. The polymerizable group is preferably acrylate. Furthermore, the number of polymerizable groups per molecule of the photopolymerizable liquid crystal compound is not particularly limited, but one or two are preferred.

[0063] Liquid crystal component 320 may not contain polymeric groups such as acrylate, methacrylate, maleimide, N-phenylmaleimide, and siloxane.

[0064] In this embodiment, the liquid crystal component 320 can be configured to have a positive dielectric constant anisotropy (Δε) as defined by the following formula (L), or it can be configured to have a negative dielectric constant. However, when the alignment films 410 and 420 described later are horizontal alignment films, a configuration with a positive dielectric constant anisotropy is preferred. By adopting this approach, strong scattering and low voltage driving can be more effectively balanced. The liquid crystal component (liquid crystal molecule) with a positive dielectric constant anisotropy is oriented in a direction parallel to the electric field direction, while the liquid crystal component (liquid crystal molecule) with a negative dielectric constant anisotropy is oriented in a direction perpendicular to the electric field direction. Furthermore, the liquid crystal component (liquid crystal molecule) with a positive dielectric constant anisotropy is also called a positive liquid crystal, and the liquid crystal component (liquid crystal molecule) with a negative dielectric constant anisotropy is also called a negative liquid crystal. In addition, the long axis direction of the liquid crystal component (liquid crystal molecule) is the direction of the slow axis. Furthermore, the direction of the long axis of the liquid crystal component (liquid crystal molecule) when no voltage is applied is also called the direction of the initial orientation of the liquid crystal component (liquid crystal molecule). Δε = (dielectric constant of the liquid crystal component (liquid crystal molecule) along its long axis) - (dielectric constant of the liquid crystal component (liquid crystal molecule) along its short axis) (L)

[0065] As liquid crystal component 320, for example, a diphenylacetylene-based liquid crystal material (a liquid crystal material having -C≡C- (carbon-carbon triple bond) as a linking group) can be used.

[0066] Preferably, the refractive index anisotropy Δn of the liquid crystal component 320 is 0.18 or higher and 0.24 or lower, the dielectric constant anisotropy Δε of the liquid crystal component 320 is 15 or higher and 25 or lower, and the rotational viscosity γ1 of the liquid crystal component 320 is 100 mPa·s or higher and 300 mPa·s or lower. By employing this method, both strong scattering and low voltage driving can be achieved, and a response speed comparable to that of conventional liquid crystal display elements without a polymer network can be realized. This effect is achieved because the refractive index anisotropy Δn, dielectric constant anisotropy Δε, and rotational viscosity γ1 of the liquid crystal component 320 are all within the aforementioned ranges.

[0067] As a specific example of a diphenylacetylene-based liquid crystal material, a liquid crystal material having the structure shown in the following general formula (L1) can be cited.

[0068] [Chemistry 1] (In the above formula, Q1 and Q2 each independently represent an aromatic ring group, X represents a fluorine group or a cyano group, and n1 and n2 each independently represent 0 or 1.)

[0069] In the above general formula (L1), n1 and n2 are not both 0. That is, the sum of n1 and n2 is 1 or 2.

[0070] The aromatic ring group in the above general formula (L1) may have substituents.

[0071] In the above general formula (L1), Q1 and Q2 are preferably each independently any structure in the following general formulas (L2-1) to (L2-7).

[0072] [Chemistry 2]

[0073] As a specific structure of a liquid crystal material having the structure shown in the above general formula (L1), the following structures can be cited as examples.

[0074] [Chemistry 3]

[0075] The preferred weight ratio of liquid crystal component 320 to polymer network 310 is 90:10 to 97:3. Specifically, the preferred weight ratio of liquid crystal component 320 is 90 or more and 97 or less; when the weight ratio of liquid crystal component 320 is 90 or more, the weight ratio of polymer network 310 is 10 or less; and when the weight ratio of liquid crystal component 320 is 97 or less, the weight ratio of polymer network 310 is 3 or more. By employing this method, both strong scattering and low-voltage driving can be effectively balanced. However, if the weight ratio of polymer network 310 exceeds 10, strong scattering is achieved, but the driving voltage becomes high; if the weight ratio of polymer network 310 is less than 3, the driving voltage is suppressed, but strong scattering is not achieved.

[0076] The liquid crystal panel 11 preferably includes an alignment film disposed between at least one of the two substrates (first substrate 100 and second substrate 200) holding the polymer-dispersed liquid crystal 300 and the polymer-dispersed liquid crystal 300. By employing this method, when the applied voltage to the polymer-dispersed liquid crystal 300 is less than a threshold voltage (including when no voltage is applied), the orientation of the liquid crystal component 320 in the polymer-dispersed liquid crystal 300 can be controlled mainly by the action of the alignment film.

[0077] The following description describes a configuration where the first alignment film 410 is disposed between the first substrate 100 and the polymer-dispersed liquid crystal 300, and the second alignment film 420 is disposed between the second substrate 200 and the polymer-dispersed liquid crystal 300, but is not limited thereto. For example, an alignment film may be disposed only between the first substrate 100 and the polymer-dispersed liquid crystal 300, or between the second substrate 200 and the polymer-dispersed liquid crystal 300; alternatively, no alignment film may be disposed between the first substrate 100 and the polymer-dispersed liquid crystal 300, or between the second substrate 200 and the polymer-dispersed liquid crystal 300. For example, the liquid crystal panel 11 may have only one of the first alignment film 410 and the second alignment film 420. Furthermore, if the alignment film is a horizontal alignment film, and the other substrate side is sliding (zero anchoring), the liquid crystal component 320 will adopt a torsional horizontal alignment state. Therefore, the same alignment state as when horizontal alignment films are disposed on both substrates can be achieved.

[0078] The first alignment film 410 and the second alignment film 420 are layers that have undergone alignment treatment to control the alignment of the liquid crystal component 320 and the photopolymerizable liquid crystal compound. They can be alignment films commonly used in the field of liquid crystal display elements, such as polyimide. The first alignment film 410 and the second alignment film 420 can be either rub-adjusted alignment films or photo-adjusted alignment films. Hereinafter, the liquid crystal component 320 and the photopolymerizable liquid crystal compound will be simply referred to as liquid crystal molecules.

[0079] Friction alignment films can be obtained, for example, by forming an alignment film material containing a polymer for friction alignment films on a substrate, rotating a roller wound with a cloth made of rayon, cotton, etc., at a constant rotation speed and distance between the roller and the substrate, and rubbing the surface of the film containing the polymer for friction alignment films in a specified direction (friction method).

[0080] Examples of polymers used in the aforementioned friction alignment films include polyimide. The friction alignment film may contain one or more polymers for the friction alignment film.

[0081] Photo-aligned films are obtained, for example, by forming an alignment film material containing a photo-aligned polymer with photofunctional groups on a substrate, and irradiating it with polarized ultraviolet light to produce anisotropy on the surface of the film containing the photo-aligned polymer (photo-alignment method).

[0082] Examples of photo-oriented polymers include those having at least one photofunctional group selected from cyclobutyl, azophenyl, chalcone, cinnamate, coumarin, stilbene, phenolic ester, and phenyl benzoate. The photo-oriented film may contain one or more photo-oriented polymers. The photofunctional groups in the photo-oriented polymer may be present in the polymer backbone, the polymer side chains, or both.

[0083] The photoreaction type of the aforementioned photooriented polymers is not particularly limited, and preferred examples include photodecomposition polymers, phototransfer polymers (preferably photofries rearrangement polymers), photoisomerization polymers, photodimerization polymers, and photocrosslinking polymers. These two methods can be used individually or simultaneously. From the viewpoint of orientation stability, photodecomposition polymers and photorearrangement polymers with a reaction wavelength (main sensitivity wavelength) around 254 nm are particularly preferred. Photoisomerization polymers and photodimerization polymers with photofunctionalized side chains are also preferred.

[0084] The main chain structure of the aforementioned photooriented polymers is not particularly limited, but preferred examples include polyamic acid structure, polyimide structure, poly(meth)acrylic acid structure, polysiloxane structure, polyethylene structure, polystyrene structure, and polyvinyl group structure.

[0085] The first alignment film 410 and the second alignment film 420 are either horizontally aligned films in which the liquid crystal component 320 is aligned parallel to the surface of the alignment film, or vertically aligned films in which the liquid crystal component 320 is aligned perpendicular to the surface of the alignment film. The first alignment film 410 and the second alignment film 420 are preferably horizontally aligned films. By adopting this method, both strong scattering and low voltage driving can be effectively balanced. The first alignment film 410 and the second alignment film 420 are horizontally aligned films, and more preferably, the liquid crystal component 320 has a positive dielectric anisotropy. By adopting this method, both strong scattering and low voltage driving can be more effectively balanced.

[0086] When the first alignment film 410 and the second alignment film 420 are horizontal alignment films, when the applied voltage to the polymer-dispersed liquid crystal 300 is less than the threshold voltage (including no applied voltage), the long axis of the liquid crystal component 320 is controlled to be oriented in the horizontal direction relative to the first alignment film 410 and the second alignment film 420 mainly by the action of the first alignment film 410 and the second alignment film 420.

[0087] That is, the liquid crystal component 320 is horizontally oriented (homogeneous orientation) relative to the first substrate 100 when no voltage is applied, and the orientation of the liquid crystal component 320 varies according to the electric field generated in the polymer-dispersed liquid crystal 300 by the voltage applied between the pixel electrode 120 and the common electrode 220, thereby enabling control over the amount of light transmitted through the polymer-dispersed liquid crystal 300. When no voltage is applied between the pixel electrode 120 and the common electrode 220, the liquid crystal component 320 is horizontally oriented due to the restraining forces of the first alignment film 410 and the second alignment film 420. When a voltage is applied between the pixel electrode 120 and the common electrode 220, the liquid crystal component 320 rotates according to the longitudinal electric field generated in the polymer-dispersed liquid crystal 300.

[0088] Here, "the major axis of the liquid crystal component 320 is oriented horizontally relative to the first alignment film 410 and the second alignment film 420" means that the tilt angle (including the pretilt angle) of the liquid crystal component 320 relative to the first alignment film 410 and the second alignment film 420 is 0 to 5°, preferably 0 to 3°, and more preferably 0 to 1°. The tilt angle of the liquid crystal component 320 refers to the angle at which the major axis (optical axis) of the liquid crystal component 320 is tilted relative to the surfaces of the first alignment film 410 and the second alignment film 420.

[0089] When the first alignment film 410 and the second alignment film 420 are vertical alignment films, when the applied voltage to the polymer-dispersed liquid crystal 300 is less than the threshold voltage (including no applied voltage), the long axis of the liquid crystal molecules is controlled to be perpendicular to the first alignment film 410 and the second alignment film 420 mainly by the action of the first alignment film 410 and the second alignment film 420.

[0090] That is, the liquid crystal component 320 is vertically oriented relative to the first substrate 100 when no voltage is applied, and the orientation of the liquid crystal component 320 varies according to the electric field generated within the polymer-dispersed liquid crystal 300 by the voltage applied between the pixel electrode 120 and the common electrode 220, thereby enabling control over the amount of light transmitted through the polymer-dispersed liquid crystal 300. When no voltage is applied between the pixel electrode 120 and the common electrode 220, the liquid crystal component 320 is vertically oriented due to the restraining forces of the first alignment film 410 and the second alignment film 420. When a voltage is applied between the pixel electrode 120 and the common electrode 220, the liquid crystal component 320 rotates according to the longitudinal electric field generated within the polymer-dispersed liquid crystal 300.

[0091] Here, the direction in which the long axis of the liquid crystal component 320 is perpendicular to the first alignment film 410 and the second alignment film 420 means that the tilt angle (including the pretilt angle) of the liquid crystal component 320 relative to the first alignment film 410 and the second alignment film 420 is 86 to 90°, preferably 87 to 89°, and more preferably 87.5 to 89°.

[0092] Next, the manufacturing method of the liquid crystal panel 11 according to this embodiment will be described. The manufacturing method of the liquid crystal panel 11 includes: an alignment film formation step, in which a first alignment film 410 and a second alignment film 420 having undergone alignment treatment are formed on one surface of a first substrate 100 and a second substrate 200, respectively; an injection step, in which the first alignment film 410 and the second alignment film 420 are arranged with the first substrate 100 and the second substrate 200 facing each other, and a composition containing liquid crystal component 320, the above-mentioned photopolymerizable liquid crystal compound and a polymerization initiator are injected between the first substrate 100 and the second substrate 200; and a light irradiation step, in which the above-mentioned composition is irradiated with light to cure the above-mentioned photopolymerizable liquid crystal compound and form a polymer network 310.

[0093] The first substrate 100 and the second substrate 200 can be manufactured using methods commonly used in the field of liquid crystal display elements.

[0094] In the above-described alignment film formation process, alignment film materials are coated onto the first substrate 100 and the second substrate 200 respectively to form a first alignment film 410 and a second alignment film 420. Examples of coating methods for the alignment film material include inkjet printing and roller coating. Next, the first alignment film 410 and the second alignment film 420 undergo alignment processing. Examples of alignment processing include friction processing by rubbing the surface of the alignment film with rollers, and photoalignment processing by irradiating the surface of the alignment film with light. According to photoalignment processing, since the alignment processing can be performed without contact with the surface of the alignment film, unlike friction processing, it has the advantage of suppressing the generation of contaminants and debris during the alignment process. The alignment film oriented by photoalignment processing is also called a photoalignment film.

[0095] The first orientation film 410 and the second orientation film 420 can be rubbed in a manner in which they are antiparallel orientations (anti-parallel orientations) or in a manner in which they are parallel orientations (parallel orientations).

[0096] In the above-described implantation process, the first alignment film 410 and the second alignment film 420 are positioned as inner sides, and the first substrate 100 and the second substrate 200 are arranged opposite to each other. A composition containing liquid crystal component 320, photopolymerizable liquid crystal compound, and polymerization initiator is implanted between the first substrate 100 and the second substrate 200. In the implantation process, the liquid crystal molecules on the first alignment film 410 side are aligned along the alignment processing direction of the first alignment film 410, and the liquid crystal molecules on the second alignment film 420 side are aligned along the alignment processing direction of the second alignment film 420. The liquid crystal molecules located between the first alignment film 410 and the second alignment film 420 continuously change their orientation between the first alignment film 410 and the second alignment film 420.

[0097] There are no particular limitations on the polymerization initiator, and any known polymerization initiator can be used. For example, Omnirad 184 (registered trademark) (manufactured by IGM Resins.BV) represented by the following chemical formula (IN1) and OXE03 (manufactured by BASF) represented by the following chemical formula (IN2) can be used as polymerization initiators.

[0098] [Chemistry 4]

[0099] [Chemistry 5]

[0100] The weight ratio of liquid crystal component 320 to photopolymerizable liquid crystal compound in the above composition is preferably 90:10 to 97:3. That is, preferably, the weight ratio of liquid crystal component 320 is 90 or more and 97 or less; when the weight ratio of liquid crystal component 320 is 90 or more, the weight ratio of photopolymerizable liquid crystal compound is 10 or less; and when the weight ratio of liquid crystal component 320 is 97 or less, the weight ratio of photopolymerizable liquid crystal compound is 3 or more. By adopting this method, both strong scattering and low-voltage driving can be effectively balanced. There is a situation where, if the weight ratio of photopolymerizable liquid crystal compound exceeds 10, strong scattering is obtained, but the driving voltage becomes high; if the weight ratio of photopolymerizable liquid crystal compound is less than 3, the driving voltage is suppressed, but strong scattering is not obtained.

[0101] In the aforementioned light irradiation process, the composition is irradiated with light, causing the photopolymerizable liquid crystal compound to solidify while forming a polymer network 310. Here, during the liquid crystal molecule orientation process in the aforementioned injection process, the photopolymerizable liquid crystal compound is a liquid crystal phase. However, during the light irradiation process, the composition is irradiated with light, and the photopolymerizable liquid crystal compound solidifies through a photopolymerization reaction, thereby maintaining its orientation state and being immobilized to form the polymer network 310, which cannot respond to an electric field. Therefore, even if a voltage is subsequently applied, the orientation direction of the polymer network 310, composed of the cured photopolymerizable liquid crystal compound, will not align with the electric field direction. On the other hand, since the orientation state of the liquid crystal component 320 is not fixed, its orientation direction aligns with the electric field direction when a voltage is applied.

[0102] Therefore, when no voltage is applied, the orientation directions of the polymer network 310 and the liquid crystal component 320 are aligned with the directions parallel to the first substrate 100 and the second substrate 200. In this state, by making their refractive indices consistent, the liquid crystal panel 11 becomes transparent. However, when a power supply is connected between the pixel electrode 120 and the common electrode 220 and a voltage is applied to the polymer-dispersed liquid crystal 300, the orientation direction of the liquid crystal component 320 is aligned with the direction of the electric field. Therefore, at the interface between the liquid crystal component 320 and the polymer network 310, due to the inconsistency in refractive indices, a light scattering state occurs, and the liquid crystal panel 11 becomes cloudy (scattering state).

[0103] The type of light used in the above-described light irradiation process is not particularly limited; for example, ultraviolet light can be used. Examples of ultraviolet light include light with a peak wavelength in the band between 340 nm and 390 nm.

[0104] In the above-mentioned light irradiation process, it is preferable to irradiate the above-mentioned composition with 5mW / cm². 2 ~50mW / cm 2 The illuminance of the light. By setting the illuminance to 5 mW / cm². 2The above allows for more complete scattering by setting the illuminance to 50 mW / cm². 2 The following methods can suppress the temperature rise during irradiation and suppress the deterioration of production yield and the deviation of characteristics.

[0105] In the above-described light irradiation process, it is preferable to irradiate the composition with 0.5 J / cm². 2 Above and 5J / cm 2 The following irradiation dose was applied. The irradiation dose was set to 0.5 J / cm². 2 The above allows for sufficient polymerization of the photopolymerizable liquid crystal compound, reducing unreacted photopolymerizable liquid crystal compound and forming a polymer network 310. As a result, the hysteresis and burn-in characteristics of the liquid crystal panel 11 are improved. Furthermore, by setting the irradiation dose to 5 J / cm²... 2 The following can improve the production cycle time.

[0106] Next, the image display method of the liquid crystal panel 11 will be described. Preferably, the liquid crystal panel 11 displays images in Field Sequential Color (FSC) mode, and the light source 21 includes multiple light-emitting elements (e.g., red LED, green LED, and blue LED) that emit light in different colors. Here, in a typical liquid crystal display element for color display, a pixel is divided into three sub-pixels: a red pixel with a color filter that transmits red light, a green pixel with a color filter that transmits green light, and a blue pixel with a color filter that transmits blue light. Although color display can be performed using the color filters provided in these three sub-pixels, about two-thirds of the light illuminating the backlight of the liquid crystal panel is absorbed by the color filters. Therefore, liquid crystal display elements using color filters suffer from low light utilization efficiency. On the other hand, by displaying images using the FSC method, the light source 21 has multiple light-emitting elements that emit light in different colors, thereby enabling color display without the use of color filters. Compared with liquid crystal display elements using color filters, light utilization efficiency is improved, the brightness of the liquid crystal panel 11 can be further increased, and low power consumption can be achieved. In addition, since no color filter is required, the liquid crystal display element 1 can be made thinner.

[0107] In the liquid crystal panel 11 that displays images in FSC mode, one frame, which constitutes the display period of a single image, is divided into multiple fields. A field is also referred to as a subframe, but the term "field" will be used consistently in the following description. For example, one frame is divided into a field (red field) that displays a red image based on the red component of the input image signal, a field (green field) that displays a green image based on the green component of the input image signal, and a field (blue field) that displays a blue image based on the blue component of the input image signal. By displaying the primary colors one by one in this manner, a color image is displayed on the liquid crystal panel.

[0108] Thus, in the liquid crystal panel 11 displaying images in FSC mode, color display is achieved by dividing the frame period into multiple fields and displaying different colors for each field, thereby eliminating the need for a color filter. Consequently, the light utilization efficiency of the FSC-mode liquid crystal display element 1 is approximately three times that of a liquid crystal display element using a color filter. Therefore, the FSC-mode liquid crystal display element is suitable for high brightness and low power consumption.

[0109] Figure 5 This is a block diagram showing the overall configuration of the liquid crystal display element according to Embodiment 1. The liquid crystal display element 1 of this embodiment comprises a preprocessing unit 1000, a timing controller 2000, a gate driver 3100, a source driver 3200, an LED driver 3300, a liquid crystal panel 11, and a light source module 20. Alternatively, the gate driver 3100 or the source driver 3200, or both, may be disposed within the liquid crystal panel 11.

[0110] The liquid crystal panel 11 includes a display unit 11A for displaying images. The preprocessing unit 1000 includes a signal separation circuit 1100, a data correction circuit 1200, a red field memory 1300(R), a green field memory 1300(G), and a blue field memory 1300(B).

[0111] In this embodiment, the light source module 20 uses multiple LEDs (light-emitting diodes) as the aforementioned multiple light-emitting elements. Specifically, the light source module 20 is composed of red LEDs, green LEDs, and blue LEDs. Furthermore, in this embodiment, the liquid crystal panel driving section is implemented by a timing controller 2000, a gate driver 3100, and a source driver 3200, and the light source driving section is implemented by an LED driver 3300. In addition, the input image data separation section is implemented by a signal separation circuit 1100.

[0112] Figure 6This diagram illustrates the configuration of one frame period in the liquid crystal display element according to Embodiment 1. One frame period is divided into a red field displaying a red image based on the red component of the input image signal DIN, a green field displaying a green image based on the green component of the input image signal DIN, and a blue field displaying a blue image based on the blue component of the input image signal DIN. In the red field, the red LED is lit after a predetermined period from the start of the field. In the green field, the green LED is lit after a predetermined period from the start of the field. In the blue field, the blue LED is lit after a predetermined period from the start of the field.

[0113] During the operation of the liquid crystal display element 1, these red, green, and blue fields are repeated. Thus, the red, green, and blue images are repeatedly displayed, and the desired color image is displayed on the display unit 11A. Furthermore, the order of the fields is not particularly limited. For example, the order could be "blue field, green field, red field." Additionally, the length of the period during which the LEDs are lit in each field can be determined considering the response characteristics of the liquid crystal.

[0114] like Figure 5 As shown, the display unit 11A is provided with multiple (n) source lines (video signal lines) SL1 to SLn and multiple (m) gate lines (scan signal lines) GL1 to GLm. Pixel forming units 4, which form pixels, are provided at each intersection of the source lines SL1 to SLn and the gate lines GL1 to GLm. That is, the display unit 11A includes multiple (n × m) pixel forming units 4. These multiple pixel forming units 4 are arranged in a matrix to form a pixel matrix of m rows × n columns. Hereinafter, the source lines SL1 to SLn will be simply referred to as source lines SL, and the gate lines GL1 to GLm will be simply referred to as gate lines GL.

[0115] Each pixel forming unit 4 includes: a TFT (thin-film transistor) 40, which is a switching element whose gate terminal is connected to a gate line GL passing through a corresponding intersection point and whose source terminal is connected to a source line SL passing through the intersection point; a pixel electrode 120, which is connected to the drain terminal of the TFT 40; a common electrode 220 and an auxiliary capacitor electrode 45, which are shared by the plurality of pixel forming units 4; a liquid crystal capacitor 42, which is formed by the pixel electrode 120 and the common electrode 220; and an auxiliary capacitor 43, which is formed by the pixel electrode 120 and the auxiliary capacitor electrode 45. The liquid crystal capacitor 42 and the auxiliary capacitor 43 constitute the pixel capacitor 46. Furthermore, in Figure 5 The display section 11A shows only the constituent elements corresponding to one pixel forming section 4.

[0116] Next, regarding Figure 5The operation of the components shown will be explained. The signal separation circuit 1100 within the preprocessing unit 1000 separates the input image signal DIN sent from the outside into red input grayscale data 1R, green input grayscale data 1G, and blue input grayscale data 1B. The data correction circuit 1200 within the preprocessing unit 1000 corrects the input grayscale data (red input grayscale data 1R, green input grayscale data 1G, and blue input grayscale data 1B) output from the signal separation circuit 1100 into data associated with the voltage applied to the liquid crystal panel 11, and outputs the corrected data as applied grayscale data (applied grayscale data 1r for the red field, applied grayscale data 1g for the green field, and applied grayscale data 1b for the blue field). A detailed description of the data correction circuit 1200 will be provided later.

[0117] The red field memory 1300(R), the green field memory 1300(G), and the blue field memory 1300(B) respectively store applied grayscale data 1r for the red field device, applied grayscale data 1g for the green field device, and applied grayscale data 1b for the blue field device output from the data correction circuit 1200.

[0118] The timing controller 2000 reads the applied grayscale data 1r for the red field, the applied grayscale data 1g for the green field, and the applied grayscale data 1b for the blue field from the red field memory 1300(R), the green field memory 1300(G), and the blue field memory 1300(B), respectively, and outputs a digital video signal DV, a gate start pulse signal GSP and a gate clock signal GCK for controlling the operation of the gate driver 3100, a source start pulse signal SP, a source clock signal SCK and a latch strobe signal LS for controlling the operation of the source driver 3200, and an LED driver 300 for controlling the operation of the LED driver 300.

[0119] The gate driver 3100 applies an effective scan signal to each gate line GL repeatedly over a period of one vertical scan, based on the gate start pulse signal GSP and the gate clock signal GCK sent from the timing controller 2000.

[0120] The source driver 3200 receives a digital video signal DV, a source start pulse signal SSP, a source clock signal SCK, and a latch strobe signal LS sent from the timing controller 2000, and applies a driving video signal to each source line SL. At this time, the source driver 3200 sequentially holds the digital video signal DV, representing the voltage to be applied to each source line SL, at the moment the pulse of the source clock signal is generated. Furthermore, at the moment the pulse of the latch strobe signal is generated, the held digital video signal DV is converted into an analog voltage. This converted analog voltage is simultaneously applied as a driving video signal to all source lines SL1 to SLn.

[0121] The LED driver 3300 outputs a light source control signal S2 based on the LED drive control signal S1 sent from the timing controller 2000, for controlling the state of each LED (red LED, green LED, and blue LED) constituting the light source module 20. In the light source module 20, the state of each LED (switching between on and off states) is appropriately switched based on the light source control signal S2. Furthermore, in this embodiment, as... Figure 6 As shown, switch the state of each LED.

[0122] As described above, by applying a scan signal to the gate lines GL1 to GLm, applying a driving video signal to the source lines SL1 to SLn, and appropriately switching the state of each LED, an image corresponding to the input image signal DIN is displayed on the display section 11A of the liquid crystal panel 11.

[0123] The light source module 20 includes a light source 21 and a reflector 22. The light source module 20 is preferably located to the side of the liquid crystal panel 11. By employing this method, the reduction in brightness under scattering conditions can be effectively suppressed.

[0124] The light source module 20 is preferably positioned separately from the liquid crystal panel 11 when viewed from above. By adopting this method, the reduction in brightness under scattering conditions can be effectively suppressed. Here, "separated from the liquid crystal panel 11" means, for example, a position separated from the liquid crystal panel 11 by more than 1 mm.

[0125] The light source module 20 is preferably disposed corresponding to one of the pair of opposite edge portions 11X and 11Y of the liquid crystal panel 11. Here, a liquid crystal panel that is transparent when no voltage is applied and diffuses when voltage is applied is also called an inverted type liquid crystal panel. In the past, for inverted type liquid crystal panels, when unpolarized light is incident perpendicularly to the panel, only single-polarized light contributes to scattering, so the transmittance in the diffused state increases to about 50%, which is not enough to allow sufficient light scattering. When light from the light source is incident perpendicularly to the main surface of the inverted type liquid crystal panel, it is believed that only single-polarized light is mismatched in refractive index between the liquid crystal component and the polymer network.

[0126] On the other hand, in this embodiment, such as Figure 1 and Figure 2 As shown, the light source module 20 is disposed corresponding to one of the pair of opposing edge portions 11X and 11Y of the liquid crystal panel 11, so that light is irradiated from a direction inclined relative to the main surface 11P on the back side of the liquid crystal panel 11. Therefore, compared with dual-polarized light, there is a refractive index mismatch between the liquid crystal components and the polymer network, so it is considered that stronger scattering can be obtained. In this embodiment, for example, stronger scattering can be obtained compared with the case of using an inverted type liquid crystal panel in which a chiral agent is introduced into the polymer-dispersed liquid crystal.

[0127] The light source 21 is located to the side of the liquid crystal panel 11. The light source 21 preferably emits Lambertian light. In a light source module using a Lambertian light source, with the same beam size, a smaller emitting area results in greater brightness of the emitting surface and greater brightness of the irradiated point. An example of the light source 21 is an LED light source. LED light sources are Lambertian light sources. The light source 21 preferably includes multiple light-emitting elements (e.g., red LEDs, green LEDs, and blue LEDs) that emit light in different colors. The light source 21 preferably has a rod-shaped form in which the multiple light-emitting elements are arranged in a straight line, and more preferably, a rod-shaped form extending along the edge of the liquid crystal panel 11.

[0128] The light source 21 is preferably positioned separately from the liquid crystal panel 11 when viewed from above. This arrangement effectively suppresses the reduction in brightness during scattering. For example, as... Figure 1 As shown, when the display surface of the rectangular liquid crystal panel 11 is viewed from the x-axis direction (from the viewing side to the back side), the light source 21 is positioned at a distance from the liquid crystal panel 11 in the z-axis direction (the direction of the short side of the liquid crystal panel 11).

[0129] The reflector 22 has the function of reflecting light incident from the light source 21 toward the liquid crystal panel 11. The reflector 22 is not particularly limited in that it only needs to reflect the incident light from the light source 21 toward the liquid crystal panel 11, but it is preferably made of a material with a high reflectivity to a high absorptivity for light from the light source 21. The reflective surface of the reflector 22 preferably contains, for example, Al or Ag. By employing this method, the reflectivity of the reflector 22 can be improved.

[0130] The reflectivity of the reflecting surface of the reflector 22 is preferably 80% or higher. Higher reflectivity is preferable, and there is no particular upper limit, but the reflectivity of the reflecting surface of the reflector 22 is, for example, 99% or lower. The reflectivity of the reflecting surface of the reflector 22 is preferably 80% or higher and 99% or lower, more preferably 95% or higher and 99% or lower.

[0131] The reflector 22 is preferably disposed on the side opposite to the liquid crystal panel 11 relative to the light source 21. The reflector 22 is preferably disposed along the light source 21.

[0132] The reflector 22 is preferably located on the side of the liquid crystal panel 11. By adopting this method, the reduction in brightness under scattering conditions can be effectively suppressed.

[0133] The reflector 22 is preferably positioned so that it is separated from the liquid crystal panel 11 when viewed from above. By adopting this method, the reduction in brightness under scattering conditions can be effectively suppressed.

[0134] The reflector 22 is preferably a single, freeform surface reflector. This effectively suppresses the reduction in brightness during scattering. Here, a freeform surface refers to a surface that can be represented by a single equation over the entire range, or by a Fourier series. A freeform surface is, for example, a surface that is represented by interpolating the intersection points with higher-order equations, given multiple intersection points and curvatures in space. This differs from simple surfaces like spheres or cylinders, which can be represented by simple mathematical formulas. More preferably, the reflector 22 is a single, freeform surface reflector in the x-axis direction.

[0135] Furthermore, the reflector 22 can also have a shape represented by more than two independent functions. By adopting this approach, the reduction in brightness under scattering conditions can be effectively suppressed. Figure 7 This diagram illustrates an example of the configuration coordinates of a mirror in Embodiment 1, where the mirror of the liquid crystal display element has a shape represented by two or more independent functions. (See diagram for example.) Figure 7 As shown, the reflector 22 more preferably has a shape in the x-axis direction that is represented by two or more independent functions. These independent functions are functions that require differentiation based on the value of x. For example, a shape represented by two or more independent functions could be... Figure 7 As shown, we can exemplify the shapes represented by the two functions z = 0.2x when 0 ≤ x ≤ 5 and z = x + 6 when 5 ≤ x ≤ 6. Since they take the same value when x = 5, they are connected at one point in the graph, but to express them using formulas, we need the shapes of both functions.

[0136] Furthermore, the reflector 22 may also have a shape represented by three or more independent functions. By adopting this method, the reduction in brightness under scattering conditions can be effectively suppressed. More preferably, the reflector 22 has a shape represented by three or more independent functions in the X-axis direction.

[0137] In addition, such as Figure 1 As shown, preferably, the reflector 22 has a collimating section 221 for collimating the light source 21 that emits Lambertian light (specifically, the light emitted from the light source 21 that emits Lambertian light), a first light distribution section 222, and a second light distribution section 223. When the thickness direction of the liquid crystal panel 11 is taken as the x-axis direction, the horizontal direction in the plane of the liquid crystal panel 11 is taken as the y-axis direction, and the vertical direction in the plane of the liquid crystal panel 11 is taken as the z-axis direction, the collimating section 221 is disposed away from the liquid crystal panel 11 in the z-axis direction, the first light distribution section 222 is disposed away from the liquid crystal panel 11 in the x-axis direction than the collimating section 221, and the second light distribution section 223 is disposed away from the liquid crystal panel 11 in the x-axis direction than the first light distribution section 222. By adopting this method, the reduction in brightness under scattering conditions can be effectively suppressed.

[0138] Collimation section 221 has the function of collimating the Lambertian light source 21. Specifically, it has the function of converting scattered light into parallel light. First light distribution section 222 and second light distribution section 223 have the function of dispersing light.

[0139] Furthermore, more preferably, 30% to 60% of the collimated total beam irradiates the first light distribution section 222, and 40% to 100% of this beam irradiates the liquid crystal panel 11. Additionally, 40% to 70% of the remaining portion of the collimated total beam that does not irradiate the first light distribution section 222 irradiates the second light distribution section 223, and 40% to 100% of this beam irradiates the liquid crystal panel 11. By employing this method, the reduction in brightness under scattering conditions can be more effectively suppressed.

[0140] Preferably, the collimation section 221, the first light distribution section 222, and the second light distribution section 223 have the same length in the y-axis direction.

[0141] Preferably, the reflector 22 has a collimating section 221 for collimating the Lambertian light source 21, a first light distribution section 222, and a second light distribution section 223. When the thickness direction of the liquid crystal panel 11 is taken as the x-axis, the horizontal direction within the surface of the liquid crystal panel 11 is taken as the y-axis, and the vertical direction within the surface of the liquid crystal panel 11 is taken as the z-axis, the collimating section 221 is disposed away from the liquid crystal panel 11 in the z-axis direction, the second light distribution section 223 is disposed away from the liquid crystal panel 11 in the x-axis direction than the collimating section 221, and the first light distribution section 222 is disposed away from the liquid crystal panel 11 in the x-axis direction than the second light distribution section 223. By adopting this method, the reduction in brightness under scattering conditions can be effectively suppressed.

[0142] Furthermore, more preferably, 30% to 60% of the collimated total beam irradiates the second light distribution section 223, and 40% to 100% of this beam irradiates the liquid crystal panel 11. Additionally, 40% to 70% of the remaining portion of the collimated total beam that does not irradiate the second light distribution section 223 irradiates the first light distribution section 222, and 40% to 100% of this beam irradiates the liquid crystal panel 11. By employing this method, the reduction in brightness under scattering conditions can be more effectively suppressed.

[0143] Preferably, the amount of light irradiated from the first light distribution section 222 onto the liquid crystal panel 11 reaches a maximum of 60% from the edge portion 11X on the side of the liquid crystal panel 11 where the light source module 20 is located, and the amount of light irradiated from the second light distribution section 223 onto the liquid crystal panel 11 reaches a maximum of 50% from the edge portion 11Y on the side of the liquid crystal panel 11 opposite to the edge portion 11X on the side where the light source module 20 is located. By adopting this method, the reduction in brightness under scattered conditions can be suppressed more effectively. Here, the amount of light reaching a maximum within a predetermined proportion from the edge portion means that the amount of light is maximum from one edge portion toward the other edge portion opposite to that edge portion within a predetermined proportion relative to the total area of ​​the liquid crystal panel.

[0144] The reflector 22 has a collimating section 221 for collimating the light source 21 that emits Lambertian light, a first light distribution section 222, and a second light distribution section 223. If the thickness direction of the liquid crystal panel 11 is set as the x-axis direction, the horizontal direction in the plane of the liquid crystal panel 11 is set as the y-axis direction, the vertical direction in the plane of the liquid crystal panel 11 is set as the z-axis direction, the length of the liquid crystal panel 11 in the z-axis direction is set as A [mm], and the point of the light source module 20 that is closest to the liquid crystal panel 11 is set as the module relative coordinate (x, z) = (0, 0), and the unit of the above module relative coordinates is set as mm, then the module relative coordinates (x1, z1) of the light source 21, the module relative coordinates (x2, z2) of the collimating section 221, the module relative coordinates (x3, z3) of the first light distribution section 222, and the module block relative coordinates (x4, z4) of the second light distribution section 223 preferably satisfy the following (Equation 1) to (Equation 15). By adopting this method, the reduction in brightness under the scattering state can be effectively suppressed. (x1, z1) = (x e ,0)…(Equation 1) z2=(4×x e ×x2) 0.5 …(Equation 2) z3=-(4×a×x3) 0.5 +(b×x3)+α…(Equation 3) z4 = -(4 × c × x4) 0.5 +(d×x4)+β…(Equation 4) 1×(A / 300)≦x e ≦30×(A / 300)…(Equation 5) 0≦x1≦60×(A / 300)…(Equation 6) 30×(A / 300)≦x2≦80×(A / 300)…(Formula 7) 45×(A / 300)≦x3≦90×(A / 300)…(Formula 8) 55×(A / 300)≦x4≦90×(A / 300)…(Formula 9) 0≦a≦50…(Equation 10) -10≦b≦10…(Equation 11) 0≦c≦50…(Equation 12) -10≦d≦10…(Equation 13) 0×(A / 300)≦α≦100×(A / 300)…(Formula 14) 0×(A / 300)≦β≦100×(A / 300)…(Formula 15)

[0145] The reflector 22 also has a third light distribution section, wherein the module relative coordinates (x5, z5) of the third light distribution section preferably satisfy the following equations (16) to (19). By adopting this method, it is possible to more effectively suppress the reduction of brightness in the scattering state. z5 = -(4 × e × x5) 0.5 +(f×x5)+γ…(Equation 16) 0≦e≦50…(Equation 17) -10≦f≦10…(Equation 18) 0×(A / 300)≦γ≦100×(A / 300)…(Formula 19)

[0146] The third light distribution section, like the first light distribution section 222 and the second light distribution section 223, has the function of dispersing light. Preferably, the collimation section 221, the first light distribution section 222, the second light distribution section 223, and the third light distribution section have the same length in the y-axis direction.

[0147] Figure 8 This is a perspective view showing an example of the light source module included in the liquid crystal display element of Embodiment 1. Furthermore, it is preferable that, as... Figure 8 As shown, when the thickness direction of the liquid crystal panel 11 is set as the x-axis direction, the horizontal direction within the surface of the liquid crystal panel 11 is set as the y-axis direction, the vertical direction within the surface of the liquid crystal panel 11 is set as the z-axis direction, and the point of the light source module 20 closest to the liquid crystal panel 11 (the point in the group of points constituting the light source module 20 closest to the liquid crystal panel 11) is set as the module relative coordinates (x, z) = (0, 0), the light source module 20 has a diffuser plate 23 with a haze of more than 1% and less than 40% on the surface of z = 0. By adopting this method, the reduction in brightness under scattering conditions can be effectively suppressed.

[0148] The diffuser plate 23, for example, has a structure in which multiple particles are dispersed within a resin-containing substrate, and has the function of diffusing transmitted light. Light emitted from the light source 21 is incident on the back side surface (light incident surface) of the diffuser plate 23 and diffuses out from the surface side surface (light emitting surface) of the diffuser plate 23 toward the liquid crystal panel 11. The diffuser plate 23 can be plate-shaped or sheet-shaped.

[0149] The diffuser plate 23 is preferably disposed on the back side of the liquid crystal panel 11. By adopting this method, the reduction in brightness under scattering conditions can be more effectively suppressed. The back side of the liquid crystal panel 11 is in the range of x ≥ 0.

[0150] In addition to the components described above, the liquid crystal display element 1 of this embodiment is composed of multiple components, including external circuits such as TCP (tape carrier package) and PCB (printed wiring substrate), optical films such as viewing angle enhancement film and brightness enhancement film, and an outer frame. These components can also be assembled from other components. There are no particular limitations on components other than those already described; components commonly used in the field of liquid crystal display elements can be used, therefore, their description is omitted.

[0151] (Implementation Method 2) In this embodiment, the features unique to this embodiment will be described in detail, and the description of content that is repeated in Embodiment 1 will be omitted. In this embodiment, the light source module, which includes a light source and a reflector, is provided corresponding to one end of a pair of opposite end portions of the liquid crystal panel, and is also provided corresponding to the other end portion. Otherwise, it is substantially the same as Embodiment 1.

[0152] Figure 9 This is a perspective view of the liquid crystal display element according to Embodiment 2. Figure 9 As shown, the liquid crystal display element 1 of this embodiment includes the light source 21 as a first light source 21A, the reflector 22 as a first reflector 22A, and the light source module 20 as a first light source module 20A as described in Embodiment 1. It also includes a second light source module 20B, which has a second light source 21B and a second reflector 22B. The second light source 21B is located on the side of the liquid crystal panel 11 and is correspondingly disposed to the other end portion 11Y of a pair of end portions 11X and 11Y. The second reflector 22B reflects the light irradiated from the second light source 21B toward the liquid crystal panel 11. By employing this method, light can be irradiated onto the liquid crystal panel 11 from both sides of the pair of end portions 11X and 11Y, thereby further improving the uniformity of the in-plane brightness of the liquid crystal panel 11.

[0153] The first light source module 20A is the same as the light source module 20 in Embodiment 1 described above. The second light source module 20B is disposed corresponding to the other end portion 11Y, and is otherwise the same as the first light source module 20A. The shapes of the first light source module 20A and the second light source module 20B may be the same or different.

[0154] (Implementation Method 3) In this embodiment, the features unique to this embodiment will be described, and the content that is repeated in Embodiment 1 will be omitted. In this embodiment, a light source module having a light source and a reflector is provided on one of a pair of opposite edge portions of the liquid crystal panel, and a light source module without a light source is provided on the other edge portion with a reflector. Otherwise, it is substantially the same as Embodiment 1.

[0155] Figure 10 This is a perspective view of the liquid crystal display element according to Embodiment 3. Figure 10 As shown, the liquid crystal display element 1 of this embodiment includes a light source 21 as a first light source 21A, a reflector 22 as a first reflector 22A, and a light source module 20 as a first light source module 20A, as described in Embodiment 1. It also includes a third light source module 20C, which has a third reflector 22C but no light source. The third reflector 22C is located on the side of the liquid crystal panel 11 and is correspondingly disposed to the other end portion 11Y of a pair of end portions 11X and 11Y, reflecting incident light towards the liquid crystal panel 11. By employing this method, light irradiated from the first light source module 20A can be reflected again onto the liquid crystal panel 11 by the third reflector 22C in the third light source module 20C, which does not have a light source, thereby further improving the uniformity of the in-plane brightness of the liquid crystal panel 11.

[0156] The first light source module 20A is the same as the light source module 20 in Embodiment 1 described above. The third light source module 20C is disposed corresponding to the other end portion 11Y and does not have a light source; otherwise, it is the same as the first light source module 20A. The shapes of the first light source module 20A and the third light source module 20C may be the same or different.

[0157] While embodiments and comparative examples are disclosed below, and the invention is described in more detail, the invention is not limited to these embodiments.

[0158] (Comparative Example 1's liquid crystal display element) Figure 11 This is a cross-sectional schematic diagram of the liquid crystal display element of Comparative Example 1. A [material / structure] was fabricated. Figure 11 The liquid crystal display element shown in Comparative Example 1. For example... Figure 11 As shown, the liquid crystal display element 1R1 of Comparative Example 1 includes: a liquid crystal panel 11R, which sequentially includes a TFT substrate 100R with a light guide plate, a polymer-dispersed liquid crystal 300, and an ITO substrate 200R; and a rod-shaped LED light source 21XR, which is disposed along the edge of the TFT substrate 100R. That is, in the liquid crystal display element 1R1 of Comparative Example 1, an LED strip (rod-shaped LED light source 21XR) is disposed on the side of the TFT substrate 100R. Light incident from the LED strip onto the side of the light guide plate is repeatedly reflected in the liquid crystal panel, and is scattered only at the part of the polymer-dispersed liquid crystal 300 where a voltage is applied, and is emitted to the front of the panel, reaching the eye of an observer located on the front of the panel.

[0159] (Liquid crystal display element of Example 1) Figure 12This is a cross-sectional schematic diagram of the liquid crystal display element in Embodiment 1. A liquid crystal display element corresponding to Embodiment 1 was fabricated. Specifically, as shown... Figure 12 As shown, the liquid crystal display element 1 of Embodiment 1 includes a liquid crystal panel 11 and a light source module 20. The liquid crystal panel 11 includes a TFT substrate as a first substrate 100, a polymer-dispersed liquid crystal 300, and an ITO substrate as a second substrate 200. The light source module 20 is disposed at a position separated from the light source module 20 by an air layer 30. The light source module 20 includes a light source 21 and a reflector 22. The light source 21 is an LED light source. The reflector 22 satisfies the configurations described in (5), (7), (8), (10), and (11) above. In the above (Equation 1) to (Equation 16), x of the reflector 22 in Embodiment 1 e =10, a=10, b=0, c=30, d=0, α=55.6347, β=39.8217.

[0160] The liquid crystal panel 11 is manufactured more specifically as follows: A first substrate 100 including a pixel electrode 120 made of ITO and a second substrate 200 including a common electrode 220 made of ITO are prepared. An alignment film material comprising a photoisomerizing polymer is coated on the side of the pixel electrode 120 opposite to the first support substrate 110 and the side of the common electrode 220 opposite to the second support substrate 210, respectively, and a photoalignment process is performed to form a first alignment film 410 and a second alignment film 420. A photoalignment process is performed on the first alignment film 410 and the second alignment film 420 in an antiparallel alignment manner.

[0161] Next, with the first alignment film 410 and the second alignment film 420 as the inner sides, the first substrate 100 and the second substrate 200 are arranged opposite each other, and a composition (polymer dispersion liquid crystal material) is injected between the first substrate 100 and the second substrate 200. This composition contains 90.6 wt% of a main liquid crystal (liquid crystal component 320) as a positive liquid crystal, 9.0 wt% of a photopolymerizable liquid crystal compound (monomer), and 8.3 wt% of a polymerization initiator. The liquid crystal component 320 uses a liquid crystal compound with Δn = 0.213, Δε = +19.1, and rotational viscosity γ1 = 344 mPa·s. The photopolymerizable liquid crystal compound uses a monomer having mesocrystalline groups, photoreactive groups, and acrylate groups. OM.651 is used as the polymerization initiator.

[0162] The liquid crystal irradiation intensity of this polymer dispersion material was 70 mW / cm. 2 Light irradiation dose 5J / cm 2The monomers are polymerized by ultraviolet (UV) light (main wavelength 365nm) for 40 seconds, forming a polymer-dispersed liquid crystal 300 between the first substrate 100 and the second substrate 200, thus producing a liquid crystal panel 11 with a unit thickness of 3μm. No black matrix layer or color filter layer is provided in the liquid crystal panel 11.

[0163] The liquid crystal panel 11 manufactured according to the above method is an inverted type (inverted mode) liquid crystal panel that is transparent when no voltage is applied and scatters when voltage is applied.

[0164] Figure 13 This is a schematic diagram illustrating a method for measuring the front scattering of the liquid crystal panel of the liquid crystal display element of Embodiment 1. Figure 14 This is a graph showing the measurement results of the front scattering of the liquid crystal panel of the liquid crystal display element of Embodiment 1. (As shown...) Figure 13 As shown, the incident angle θ from the light source was changed for the liquid crystal panel 11 of Example 1, and front scattering was measured. The result was... Figure 14 The scattering characteristics are shown.

[0165] The light source module 20 is manufactured more specifically in the following manner. Furthermore, the thickness direction of the liquid crystal panel 11 is set as the x-axis direction, the horizontal direction within the surface of the liquid crystal panel 11 is set as the y-axis direction, and the vertical direction within the surface of the liquid crystal panel 11 is set as the z-axis direction.

[0166] Figure 15 This is a top view schematic diagram of the light source of the light source module of the liquid crystal display element in Embodiment 1. Figure 15 The light source 21 of the light source module 20 in Embodiment 1 shown is a rod-shaped light source with 144 red LED chips 21RL, green LED chips 21GL, and blue LED chips 21BL arranged in a central 0.8cm×36cm area on a 3cm×42cm LED strip. Color display can be achieved by driving the light source 21 with FSC.

[0167] Figure 16 This is a diagram showing the configuration coordinates of the liquid crystal panel and the light source module of the liquid crystal display element in Embodiment 1. Figure 16 This indicates the configuration of the liquid crystal display element 1 in Embodiment 1 when viewed from a horizontal (cross-section) perspective. The point of the light source module 20 closest to the liquid crystal panel 11, i.e., the end of the reflector 22, is taken as the origin (0, 0). The horizontal axis is the x-axis direction, and the vertical axis is the z-axis direction. The unit is mm.

[0168] The module relative coordinates (x1, z1) of the LED strip (light source 21) are (10, 0), and the light source 21 is configured to emit light parallel to the z-axis direction. The reflector 22 consists of three parts: a collimating part 221, a first light distribution part 222, and a second light distribution part 223. When the module relative coordinates (x2, z2) of the collimating part 221, the module relative coordinates (x3, z3) of the first light distribution part 222, and the module relative coordinates (x4, z4) of the second light distribution part 223 are set, within the range of 0 ≤ x2 ≤ 54.5, z2 = (40 × x2). 0.5 Within the range of 54.5 ≤ x3 ≤ 77, the condition z3 = -(40 × (x3 - 52.5)) is satisfied. 0.5 +55.6347. Within the range of 77 ≤ x4 ≤ 88.5, z4 = -(120 × (x4 - 75)) is satisfied. 0.5 +39.8217. Furthermore, the area of ​​the active region of the LCD panel 11 is 300mm in the z-axis direction and 400mm in the y-axis direction. The xz coordinates of the major axis of the Y-axis at the top of the LCD panel 11 are (0, -10), and the xz coordinates of the major axis of the Y-axis at the bottom of the LCD panel 11 are (0, -310).

[0169] In the liquid crystal display element 1 of Embodiment 1, when the polymer-dispersed liquid crystal 300 is in a state where no voltage is applied (e.g., the applied voltage is 0V), the light irradiating the liquid crystal panel 11 passes through the lower side of the screen, so the light cannot reach the eyes of the observer located on the front of the panel. When the polymer-dispersed liquid crystal 300 is in a state where a voltage is applied (e.g., the applied voltage is 8.5V), the light irradiating the liquid crystal panel 11 is emitted to the front of the panel, and the light reaches the eyes of the observer located on the front of the panel.

[0170] (Evaluation of Example 1 and Comparative Example 1) Figure 17 This is a front view schematic diagram illustrating the upper, central, and lower portions of the screen of a liquid crystal display element. The liquid crystal display elements of Embodiment 1 and Comparative Example 1 were determined... Figure 17 The brightness of the central portion of the screen, and the in-plane brightness ratios of the upper, central, and lower portions of the screen are shown. Table 1 below shows the results of the brightness characteristics when a voltage is applied to the entire surface of the liquid crystal panel. Furthermore, the brightness was determined using a luminance meter (SR-UL2) manufactured by Topcon. In addition, the power settings of the LED light source in Example 1 and Comparative Example 1 were the same.

[0171] [Table 1]

[0172] According to Table 1 above, in Example 1, the illuminance distribution in the surface can be appropriately distributed by the light distribution of the reflector 22. More specifically, the illuminance can be increased at a position far from the screen, the brightness uniformity in the surface can be improved, and high brightness can be obtained in the center of the screen.

[0173] On the other hand, in Comparative Example 1, a portion of the light reflected by the light guide plate is diffracted and lost in components such as the TFT. Therefore, the further away from the LED light source, the greater the light loss, and the brightness decreases in areas far from the LED light source. Explanation of reference numerals in the attached figures

[0174] 1. 1R1: Liquid Crystal Display Element 1B, 1G, 1R: Input grayscale data 1b, 1g, 1r: Apply grayscale data 1RB: Transparent Display 2R: Box 4: Pixel forming section 11, 11R: LCD panel 11A: Display Unit 11P: Main surface on the back side 11X, 11Y: End edge portion 20: Light source module 20A: First Light Source Module 20B: Second Light Source Module 20C: Third Light Source Module 21, 21A, 21B: Light source 21BL: Blue LED chip 21GL: Green LED Chip 21RL: Red LED chip 21XR: LED light source 22, 22A, 22B, 22C: Reflectors 23: Diffuser plate 30: Air layer 40: TFT (Thin Film Transistor) 42: Liquid Crystal Capacitor 43: Auxiliary capacitor 45: Auxiliary capacitor electrode 46: Pixel Capacitor 100: First substrate 100R: TFT substrate 110: First support substrate 120: Pixel Electrode 200: Second substrate 200R: ITO substrate 210: Second support substrate 220: Common electrode 221: Collimation part 222: First light distribution department 223: Second light distribution section 300: Polymer-dispersed liquid crystal 310: Polymer Network 320: Liquid crystal composition 410: First orientation film 420: Second-Orientation Film 1000: Pre-processing Department 1100: Signal separation circuit 1200: Data Correction Circuit 1300(R): Red Field Memory 1300(G): Green Field Memory 1300(B): Blue Field Memory 2000: Timing Controller 3100: Gate driver 3200: Source Driver 3300: LED Driver DIN: Input image signal DV: Digital Video Signal GCK: Gate clock signal GSP: Gate Start-up Pulse Signal GL, GL1~GLm: Gate lines LS: Latch strobe signal S1: LED driver control signal S2: Light source control signal SCK: Source clock signal SL, SL1~SLn: Source lines SSP: Source Startup Pulse Signal

Claims

1. A liquid crystal display element, characterized in that, include: A liquid crystal panel having a polymer network and a polymer-dispersed liquid crystal containing liquid crystal components; as well as A light source module includes a light source and a reflector. The light source is located to the side of the liquid crystal panel, and the reflector reflects the light emitted by the light source toward the liquid crystal panel. The liquid crystal panel includes a pair of end edge portions that are opposite each other. The light source module is provided corresponding to one of the pair of end edge portions. The reflector has a collimating section for collimating the light source that emits Lambertian light, a first light distribution section, and a second light distribution section. When the thickness direction of the liquid crystal panel is taken as the x-axis, the horizontal direction within the surface of the liquid crystal panel is taken as the y-axis, and the vertical direction within the surface of the liquid crystal panel is taken as the z-axis... The collimation section is positioned away from the liquid crystal panel in the z-axis direction. The first light distribution section is positioned further away from the liquid crystal panel in the x-axis direction than the collimating section. The second light-distributing portion is positioned further away from the liquid crystal panel in the x-axis direction than the first light-distributing portion. Of the collimated total light beam, 30% to 60% illuminates the first light distribution section, and of this portion, 40% to 100% illuminates the liquid crystal panel. Of the collimated total light beam, more than 40% and less than 70% that did not reach the first light distribution section illuminate the second light distribution section, and of these, more than 40% and less than 100% illuminate the liquid crystal panel.

2. The liquid crystal display element according to claim 1, characterized in that, The light source is a first light source, the reflector is a first reflector, and the light source module is a first light source module. The liquid crystal display element further includes a second light source module, which has a second light source and a second reflector. The second light source is located on the side of the liquid crystal panel and is disposed corresponding to the other end edge portion of the pair of end edge portions. The second reflector reflects the light irradiated by the second light source toward the liquid crystal panel side.

3. The liquid crystal display element according to claim 1, characterized in that, The light source is a first light source, the reflector is a first reflector, and the light source module is a first light source module. The liquid crystal display element further includes a third light source module, which has a third reflector but no light source. The third reflector is located on the side of the liquid crystal panel and is disposed corresponding to the other end of the pair of end portions, and reflects the incident light toward the liquid crystal panel side.

4. The liquid crystal display element according to any one of claims 1 to 3, characterized in that, The reflector is a single, freeform surface reflector.

5. The liquid crystal display element according to any one of claims 1 to 3, characterized in that, The reflector has a shape that can be represented by two or more independent functions.

6. The liquid crystal display element according to any one of claims 1 to 3, characterized in that, The reflector has a shape that can be represented by three or more independent functions.

7. The liquid crystal display element according to claim 1, characterized in that, The amount of light irradiated from the first light distribution unit onto the liquid crystal panel reaches a maximum of 60% from the edge portion of the liquid crystal panel on the side where the light source module is located. The amount of light irradiated from the second light distribution unit onto the liquid crystal panel reaches a maximum value of 50% from the edge portion of the liquid crystal panel opposite to the edge portion on the side where the light source module is located.

8. The liquid crystal display element according to any one of claims 1 to 3 and 7, characterized in that, When the thickness direction of the liquid crystal panel is set as the x-axis, the horizontal direction within the surface of the liquid crystal panel is set as the y-axis, the vertical direction within the surface of the liquid crystal panel is set as the z-axis, and the point of the light source module that is closest to the liquid crystal panel is set as the module's relative coordinates (x, z) = (0, 0), The light source module has a diffuser plate on the z=0 surface, and the diffuser plate has a haze of more than 1% and less than 40%.

9. The liquid crystal display element according to claim 8, characterized in that, The diffuser plate is disposed on the back side of the liquid crystal panel.

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