KR102644001B1 - Transparent liquid crystal display device - Google Patents

Abstract

The present invention does not require a color filter and a polarizer to implement a transparent display device, and the alignment film composition process and ultraviolet ray irradiation process can be omitted, and the liquid crystal molecules inside the liquid crystal layer are uniformly dispersed and the arrangement direction is consistently aligned. The goal is to provide a transparent liquid crystal display device that can
The present invention includes a liquid crystal layer; Inside the liquid crystal layer, it includes a liquid crystal sheet including micro tubes of a core-shell structure, the core of the micro tube includes a first liquid crystal molecule, the shell includes a liquid crystal polymer, and the liquid crystal sheet includes the A liquid crystal display device is provided in which microtubes are formed in the form of a non-woven fabric intertwined with each other.

Description

Transparent liquid crystal display device {TRANSPARENT LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates to a transparent liquid crystal display device, and in particular, to a transparent liquid crystal display device including a liquid crystal sheet formed of micro tubes in a liquid crystal layer, and liquid crystal molecules impregnated between spaces between the micro tubes within the liquid crystal sheet.

The liquid crystal display device includes a liquid crystal panel and a backlight unit composed of liquid crystals and thin film transistors. The arrangement of the liquid crystals changes depending on the voltage applied to each pixel of the liquid crystal panel, and accordingly, the transmittance of light emitted from the backlight unit changes. Adjusted to display an image.

A liquid crystal display device can have high transparency depending on the arrangement state of the liquid crystals, and this property can be used to implement a transparent display device.

The purpose of the present invention is to not require a color filter and a polarizer to implement a transparent display device, the alignment film composition process and the ultraviolet ray irradiation process can be omitted, and the liquid crystal molecules inside the liquid crystal layer are uniformly dispersed and the arrangement direction is changed. The goal is to provide a transparent liquid crystal display device that can be aligned consistently.

In order to achieve the above object, the present invention includes a liquid crystal sheet including a liquid crystal layer and, inside the liquid crystal layer, micro tubes of a core-shell structure, and the core of the micro tube contains first liquid crystal molecules. It provides a liquid crystal display device in which the shell includes a liquid crystal polymer, and the liquid crystal sheet is formed in the form of a non-woven fabric in which the micro tubes are entangled with each other.

In addition, it further includes second liquid crystal molecules, wherein the second liquid crystal molecules are impregnated in the space where the micro tubes of the liquid crystal sheet are spaced apart.

In addition, when an electric field is not applied to the liquid crystal layer, the arrangement direction of the first liquid crystal molecules and the second liquid crystal molecules is the same as the arrangement direction of the liquid crystal polymer contained in the shell of the micro tube.

In addition, the abnormal refractive index (n _e ) and normal refractive index ( _no ) of the first liquid crystal molecules are the same as the abnormal refractive index (ne _e ) and normal refractive index ( _no ) of the second liquid crystal molecules, respectively. do.

When an electric field is not applied to the liquid crystal layer, the light emitted from the backlight is totally reflected inside the liquid crystal layer to display a transparent state, and when an electric field is applied to the liquid crystal layer, the light emitted from the backlight is displayed in a transparent state. A liquid crystal display device is provided that displays an image by scattering outside the liquid crystal layer.

In addition, the liquid crystal polymer contained in the shell of the micro tube includes a first monomer and a second monomer, and is formed by polymerizing the first monomer and the second monomer, and the first monomer is formed in a chain structure, The second monomer provides a liquid crystal display device formed of the third liquid crystal molecule.

In addition, the abnormal refractive index (n _e ) and normal refractive index ( _no ) of the third liquid crystal molecules are the same as the abnormal refractive index (n _e ) and normal refractive index ( _no ) of the first liquid crystal molecules, respectively. do.

Additionally, a liquid crystal display device that displays colors using a field sequential color driving method is provided.

Another embodiment of the present invention includes forming a micro tube including a core containing a first liquid crystal molecule and a shell containing a liquid crystal polymer; It provides a method of manufacturing a liquid crystal display device, comprising forming a liquid crystal sheet including the micro tubes, wherein the liquid crystal sheet is formed in the form of a non-woven fabric in which the micro tubes are entangled with each other.

And, the liquid crystal sheet includes preparing the first liquid crystal molecule in a first capillary of a nozzle and preparing the liquid crystal polymer in a second capillary of a nozzle; applying an electric field to the nozzle to discharge the first liquid crystal molecules and the liquid crystal polymer from the nozzle, respectively; A method of manufacturing a liquid crystal display device is provided, including collecting the first liquid crystal molecules and the liquid crystal polymer released while a collection plate rotates.

And, preparing the liquid crystal sheet including the micro tubes; forming a first electrode on a first substrate; adhering the liquid crystal sheet onto the first electrode; Applying second liquid crystal molecules on the liquid crystal sheet and impregnating the space where the micro tubes of the liquid crystal sheet are spaced apart by the second liquid crystal molecules; A method of manufacturing a liquid crystal display device is provided, further comprising the step of adhering a second electrode to the liquid crystal sheet.

As described above, the liquid crystal display device of the present invention is a transparent liquid crystal display device in which liquid crystal molecules are uniformly dispersed within the liquid crystal layer and the arrangement direction is consistently aligned by impregnating liquid crystal molecules into a liquid crystal sheet in the form of a non-woven fabric in which micro tubes are intertwined. can be implemented. And since transparent and scattering states can be implemented by using the difference in refractive index between liquid crystal molecules and liquid crystal polymers, color filters and polarizers are not required to implement a transparent liquid crystal display device. In addition, a transparent liquid crystal display device can be implemented without the need for a separate alignment film composition process or ultraviolet irradiation process, which has the effect of simplifying the process and reducing manufacturing costs.

1 is a diagram showing a cross section of a liquid crystal panel of a transparent liquid crystal display device according to a first embodiment of the present invention.
2A and 2B are diagrams showing a cross section of a liquid crystal panel when an electric field is or is not applied to the liquid crystal layer of a transparent liquid crystal display device according to a second embodiment of the present invention.
FIG. 3A is a diagram showing a cross section of a liquid crystal sheet according to a third embodiment of the present invention, and FIG. 3B is a diagram showing a cross section of a liquid crystal panel of a transparent liquid crystal display device according to a third embodiment of the present invention.
Figure 4 is a diagram showing the structure of a micro tube according to a third embodiment of the present invention.
5A and 5B are diagrams showing a cross section of a liquid crystal sheet when an electric field is or is not applied to the liquid crystal layer according to a third embodiment of the present invention.
Figure 6 is a diagram showing the manufacturing process of a liquid crystal sheet according to a third embodiment of the present invention.
7A to 7D are diagrams showing the manufacturing process of a liquid crystal panel according to a third embodiment of the present invention.

The word “impregnation” used in the present invention means allowing a gaseous or liquid substance to penetrate or permeate into a specific object.

Hereinafter, an embodiment according to the present invention will be described in detail with reference to the drawings.

1 is a diagram showing a cross section of a liquid crystal panel of a transparent liquid crystal display device according to a first embodiment of the present invention.

The liquid crystal panel 100 of the liquid crystal display device according to the first embodiment of the present invention may include a first substrate 110 and a second substrate 120 that face each other and are spaced apart from each other. A liquid crystal layer 130 containing liquid crystal molecules 131 may be interposed between the two substrates 120.

The upper part of the first substrate 110 may be provided with a plurality of gate wires (not shown) arranged in parallel and spaced at a predetermined distance, and data wires (not shown) that intersect the gate wires to define a pixel area.

A thin film transistor (not shown) may be formed at the intersection of the gate wire and the data wire, and a first electrode 140 and a second electrode 150 may be provided in the pixel area where an image is displayed.

The first electrode 140 and the second electrode 150 may be formed of a transparent conductive material to implement a transparent display device, and the first electrode 140 may be formed on the top of the first substrate 110. , the second electrode 150 may be formed on the lower part of the second substrate 120.

A thin film transistor may be composed of a gate electrode, a gate insulating film, a semiconductor layer, a source electrode, and a drain electrode.

Additionally, a protective film may be formed on the front surface of the array substrate including the thin film transistor, and a first electrode 140 may be formed on top of the protective film to be electrically connected to the drain electrode of the thin film transistor.

And, according to the data signal applied to the thin film transistor, an electric field is generated between the first electrode 140 and the second electrode 150 to change the arrangement of the liquid crystal molecules 131.

The liquid crystal molecules 131 may change their position and arrangement direction irregularly when an electric field is not applied. Therefore, the liquid crystal molecules 131 must be aligned in a certain direction. As a method of forming the orientation direction, an alignment film made of polyimide (PI), etc. is formed on a substrate and the surface of the orientation film is rubbed in a predetermined direction with a cloth such as rayon or cotton, or a rubbing method is used, or a polarized ultraviolet ray is used. A photo-alignment method that generates optical anisotropy on the surface of the polyimide alignment film by irradiation can be used. Through this method of forming the orientation direction, the liquid crystal molecules 131 are strongly bound to the surface of the substrate and are arranged in a certain direction. In the first embodiment of the present invention, an alignment film 160 is formed on the top of the first electrode 140 and the bottom of the second electrode 150 to form the alignment direction of the liquid crystal molecules 131.

Since the liquid crystal panel 100 cannot emit light on its own, it may include a backlight unit, which is a device that separately supplies light. The liquid crystal display device according to the present invention includes a backlight unit (not shown) including a backlight (not shown) and a backlight driver (not shown) that drives the backlight, a light guide plate (not shown), a reflector (not shown), and an optical sheet (not shown). Poetry) may be included. Backlight units are divided into direct type and edge type depending on the location of the light source.

The direct type backlight unit places the light source at the bottom of the liquid crystal panel 100 to directly supply the light emitted from the light source to the liquid crystal panel 100, and the side type backlight unit places the light source at the bottom of the liquid crystal panel 100. By placing a light guide plate on and placing a light source on one side of the light guide plate, the light emitted from the light source is indirectly supplied to the liquid crystal panel 100 using refraction and reflection in the light guide plate.

The backlight unit according to the present invention can use either of these two methods. In addition, Cold Cathode Fluorescent Lamp (CCFL), External Electrode Fluorescent Lamp (EEFL), and Light Emitting Diode (LED) can be used as light sources, and other lights can be used as liquid crystals. Any device that can be supplied to the panel 100 can be used.

The light guide plate is disposed to guide the light emitted from the light source to the front of the liquid crystal panel 100, and the light incident from the light source spreads evenly as it travels inside the light guide plate by total reflection to provide a surface light source to the liquid crystal panel.

The reflector is located below the light guide plate, and can improve the luminance of light emitted from the light source by reflecting light passing through the back of the light guide plate toward the liquid crystal panel 100.

The optical sheet includes a diffusion sheet, a prism sheet, and a protective sheet, and is located on top of the light guide plate. It diffuses or condenses the light passing through the light guide plate to create a more uniform surface light source and then emits it to the liquid crystal panel 100. can do.

A polarizing plate 170 having a first polarization axis may be attached to the lower part of the first substrate 110, and a polarizing plate 170 having a first polarization axis may be attached to the upper part of the second substrate 120. Red, green, and blue plates are sequentially and repeatedly arranged corresponding to each pixel area. A color filter layer 180 including color filters 181, 182, and 183 may be formed.

The red, green, and blue color filters 181, 182, and 183 may be made of red, green, and blue color dyes, respectively, and may have the same polarization axis as the first polarization axis of the polarizer 170.

The red, green, and blue color filters 181, 182, and 183 transmit light having the same color as the self-polarized light polarized in a direction parallel to the first polarization axis and transmit light having a color other than the self-color. Absorbs all light.

Additionally, the red, green, and blue color filters 181, 182, and 183 transmit all light polarized in a direction perpendicular to the first polarization axis.

Accordingly, light having a polarization axis parallel to the first polarization axis is transmitted only through the color filter having the same color as the color filter among the red, green, and blue color filters 181, 182, and 183, and is absorbed by the remaining color filters to change the color. It can be implemented. Light having a polarization axis perpendicular to the first polarization axis is transmitted through all of the red, green, and blue color filters 181, 182, and 183, thereby displaying a transparent state. Accordingly, it is possible to implement a transparent display device that allows viewing objects or images located on the other side of the liquid crystal display device.

2A and 2B are diagrams showing a cross section of a liquid crystal panel when an electric field is or is not applied to the liquid crystal layer of a transparent liquid crystal display device according to a second embodiment of the present invention.

Liquid crystal molecules 231 may be included within the liquid crystal layer 230, and liquid crystal polymers 232 formed in a network form by polymerizing photo-reactive liquid crystal molecules may be included.

When an electric field (E) is applied between the first electrode 240 and the second electrode 250 to display an image on a liquid crystal display device, the long axis of the liquid crystal molecules 231 is aligned in the direction of the electric field, as shown in FIG. 2A. do. However, since the liquid crystal polymer 232 forms a network by polymerizing liquid crystal molecules, the magnitude of the electric field applied between the first electrode 240 and the second electrode 250 to change the arrangement direction of the liquid crystal molecules 231 is sufficient to The arrangement direction of the liquid crystal polymer 232 cannot be changed. Therefore, the long axis of the liquid crystal molecules 231 is aligned in the direction of the electric field, and the long axis of the liquid crystal molecules forming the liquid crystal polymer 232 remains aligned in a direction perpendicular to the direction of the electric field, resulting in a difference in the alignment direction. I do it. As a result, a difference in the refractive index of the liquid crystal molecules 231 and the liquid crystal polymer 232 occurs in the direction of the electric field applied to the liquid crystal layer, so that the light emitted from the backlight cannot directly pass through the liquid crystal layer 230 and is absorbed into the liquid crystal molecules 231. ) or is scattered while colliding with the liquid crystal polymer 232. Since the scattered light is emitted to the outside of the liquid crystal display device to express an image, an image can be created accordingly.

The liquid crystal display device according to the second embodiment can display colors using a field sequential color (FSC) driving method. The field sequential color driving method does not use a color filter, but sequentially drives light sources that emit the three primary colors of light, red, green, and blue, to display mixed colors using the afterimage effect that appears in the human eye. There is a way to do this.

To explain in more detail, one frame displaying an image is divided into three sub-frames displaying red, green, and blue colors, and the light sources of each color are turned on at intervals in time. The time to turn on the light source within the subframe section is the time excluding the data writing time and the liquid crystal response time. If 1 frame is displayed during a time when humans cannot visually distinguish color changes, and light sources emitting red, green, and blue colors are flashed sequentially, even if each light source stops emitting light, it will not be recognized during 1 frame. It becomes impossible. At this time, the colors displayed by the blinking light source become an afterimage and are mixed, allowing multiple colors to be displayed. For example, if a red light source is turned on during one sub-frame section and a green light source is turned on during the next sub-frame section, a yellow color can be displayed.

When a color filter is used to display color, there is a disadvantage in that the luminance is lowered because the light emitted from the backlight may be lost while passing through the color filter. On the other hand, the field sequential color driving method does not use a color filter, so light is not lost due to the color filter and the luminance is relatively increased.

Meanwhile, when an electric field is not applied between the first electrode 240 and the second electrode 250, the liquid crystal molecules 231 are aligned in a direction perpendicular to the direction in which the electric field is applied. Since there is no difference in the arrangement direction of the liquid crystal molecules 231 and the liquid crystal polymer 232, light passes through the liquid crystal layer 230 as is. Accordingly, the light reflected from an object or image located on the opposite side of the liquid crystal display device passes through the liquid crystal display device as is, so that a transparent state can be displayed.

In the second embodiment, the liquid crystal polymer 232 can be formed by mixing photoreactive liquid crystal molecules and monomers and then irradiating them with ultraviolet (UV) rays. The liquid crystal polymer 232 may be formed in a network form and may be formed of a photo-reactive liquid crystal molecule and a photo-curable monomer made of a transparent material that allows light to pass through. This can be formed through the process of mixing liquid crystal molecules and monomers together, irradiating ultraviolet rays to the mixed solution, and then changing the liquid crystal molecules and monomers into a liquid crystal polymer 232 by phase separation.

However, during the process of forming the liquid crystal polymer 232 by irradiating ultraviolet rays, depending on the ultraviolet irradiation conditions or the external environment, the arrangement direction of the liquid crystal polymer is uniformly aligned, and the liquid crystal polymer 232 is uniformly distributed inside the liquid crystal layer 230. It may be difficult to place it properly.

As such, in the second embodiment of the present invention, a transparent display device can be implemented without the need for the polarizer 170 and the color filter layer 180 included in the liquid crystal display device of the first embodiment, and the field sequential color driving method allows color change. can be displayed, which has the effect of eliminating the need to form the color filter layer 180. However, a process for forming an alignment film 260 is necessary to prevent the position and arrangement direction of the liquid crystal molecules 231 from changing irregularly, and a separate ultraviolet irradiation process is required to form the liquid crystal polymer 232, so the manufacturing process and manufacturing costs may increase. In addition, during the ultraviolet irradiation process, it is difficult to consistently align the arrangement direction of the liquid crystal polymers 232 and uniformly arrange the liquid crystal polymers 232 within the liquid crystal layer. And, in order to orient the liquid crystal molecules 231, it is necessary to form an alignment film 260.

FIG. 3A is a diagram showing a cross section of a liquid crystal sheet according to a third embodiment of the present invention, FIG. 3B is a diagram showing a cross section of a liquid crystal panel of a transparent liquid crystal display device according to a third embodiment of the present invention, and FIG. 4 is a diagram showing a cross section of a liquid crystal sheet according to a third embodiment of the present invention. This is a diagram showing the structure of a micro tube according to a third embodiment of the present invention.

As shown in FIG. 3B, the first electrode 340 may be formed on the top of the first substrate 310, and the second electrode 350 may be formed on the bottom of the second substrate 320. A liquid crystal layer 330 may be interposed between the first electrode 340 and the second substrate 320. The first electrode 340 and the second electrode 350 may be formed of a transparent conductive material, for example, indium-tin-oxide (ITO) or indium-zinc-oxide (IZO). there is.

The inside of the liquid crystal layer 330 may include second liquid crystal molecules 331 and a liquid crystal sheet 400, and the liquid crystal sheet 400 is a micro tube consisting of a core 420 and a shell 430 as shown in Figure 3a ( 410) may be included.

Like a non-woven fabric formed by irregularly entangling a plurality of fiber strands according to their mutual characteristics and then stacking the tangled plurality of fiber strands, the liquid crystal sheet 400 is formed by randomly entangling a plurality of micro tubes 410. By forming it into a shape and then continuously stacking it, it can have a form similar to a non-woven fabric. In Figure 3a, for convenience of explanation, a cross-section of the liquid crystal sheet 400 in which the micro tubes 410 are regularly arranged in a lattice shape is shown, but the structure is not limited to this and the micro tubes 410 are irregularly arranged to form a liquid crystal sheet ( 400) may be formed.

Just as empty spaces are formed between fiber strands constituting a non-woven fabric, empty spaces may be formed between micro tubes 410 in the liquid crystal sheet 400. This space is formed randomly, but is arranged uniformly when looking at the liquid crystal sheet as a whole, so by impregnating the empty space with the second liquid crystal molecule 331, it is equivalent to uniformly arranging the liquid crystal molecules inside the liquid crystal layer 330. The effect can be obtained. The micro tube 410 can be formed as a structure consisting of a core 420 and a shell 430. The outer diameter of the micro tube is 3 to 5 μm, and the inner diameter, which is the diameter of the core, is 1. ~3 μm is preferred. This means that if the diameter of the shell 430 (=outer diameter of the micro tube - inner diameter) is smaller than the wavelength of visible light with a wavelength of 400 to 800 nm, the light emitted from the backlight is not scattered by the liquid crystal sheet 400. This is because it can be transmitted as is. Therefore, it is desirable to make the diameter of the shell 430 longer than the wavelength of visible light so that an image can be displayed by scattering the light emitted from the backlight.

The core 420 may contain first liquid crystal molecules 421. The normal refractive index (n _o ) and abnormal refractive index (n _e ) of the first liquid crystal molecule 421 are the second liquid crystal molecules included in the space where the micro tubes 410, which are empty spaces of the liquid crystal sheet 400, are spaced apart from each other. (331) may be the same as the normal refractive index (n _o ) and the abnormal refractive index (n _e ), respectively. This is to form the same arrangement direction of the first liquid crystal molecules 421 and the second liquid crystal molecules 331, and when an electric field is applied inside the liquid crystal layer 330, the first liquid crystal molecules 421 and the second liquid crystal molecules (331) are arranged in the same direction and can display a transparent state.

When an electric field is applied to the liquid crystal layer 330, the long axes of the first liquid crystal molecules 421 and the second liquid crystal molecules 331 are aligned in the direction in which the electric field is applied, and the electric field is applied to the liquid crystal layer 330. In order for the short axis of the liquid crystal molecules to be aligned in the direction in which the electric field is applied when this is not possible, the first liquid crystal molecules 421 and the second liquid crystal molecules 331 have a difference between the abnormal refractive index (n _e ) and the normal refractive index (n _o ). It is preferable that the refractive index anisotropy is 0.2 to 0.3. This means that if the refractive index anisotropy is smaller than the above numerical range, there is no difference in the size of the long axis and short axis of the liquid crystal molecules, so the arrangement direction of the liquid crystal molecules does not change even when an electric field is applied to the liquid crystal layer. If the refractive index anisotropy is larger than the above numerical range, birefringence occurs. This is because images may be displayed repeatedly on the display device. Therefore, in order to display a transparent state and display an image normally, it is desirable for the refractive index anisotropy to be in the range of 0.2 to 0.3. For this purpose, the normal refractive index (n _o ) may be 1.5, and the abnormal refractive index (n _e ) may be 1.7 to 1.8.

The shell 430 may be formed to include a main chain liquid crystal polymer 440, and the main chain liquid crystal polymer 440 is polymerized after alternately arranging the first monomer 441 and the second monomer 442. It can be formed through a process.

The first monomer 441 may be formed as a chain structure including an alkyl group or an alkoxy group. The first monomer 441 can control the solubility when the micro tube 410 is dissolved in a solvent and can determine the form of the liquid crystal phase formed by the second monomer 442.

The second monomer 442 may be formed of the third liquid crystal molecule 443, and the normal refractive index (n _o ) and abnormal refractive index (ne _e ) of the third liquid crystal molecule 443 are those of the first liquid crystal molecule 421. and may be the same as the normal refractive index (n _o ) and the abnormal refractive index (n _e ) of the second liquid crystal molecule 331, respectively. This is to ensure that the arrangement direction of the first liquid crystal molecules 421 and the second liquid crystal molecules 331 is the same as that of the third liquid crystal molecules 433 when an electric field is not applied.

A liquid crystal sheet 400 in the form of a non-woven fabric can be formed by processing a plurality of micro tubes 410 that can have such a structure to be entangled with each other. Since the micro tubes 410 can be randomly arranged to form the liquid crystal sheet 400, the main chain liquid crystal polymer 440 can be uniformly arranged inside the liquid crystal layer 330.

The first liquid crystal molecule 421 included in the liquid crystal sheet 400 having this structure is contained inside the core 420 of the micro tube 410 and is surrounded by the shell 430, and is included in the shell 430. It may be arranged in the same direction as the arrangement direction of the third liquid crystal molecules 443.

In addition, the second liquid crystal molecules 331 are impregnated into the space where the micro tubes 410, which are empty spaces of the liquid crystal sheet 400, are separated from each other, and the space outside the liquid crystal sheet 400 and inside the liquid crystal layer 330. , It can be arranged in the same direction as the arrangement direction of the first liquid crystal molecules 421 and the third liquid crystal molecules 443, and during the impregnation process, the liquid crystal layer 330 is evenly permeated into the space where the micro tubes 410 are spaced apart. It can be placed uniformly inside. Therefore, the first liquid crystal molecules 421 and the second liquid crystal molecules 331 can be uniformly arranged inside the liquid crystal layer 330 or the liquid crystal sheet 400, and since the alignment directions are aligned, a separate alignment film is not required. It will not be done.

Also, by using a field sequential color driving method as in the second embodiment of the present invention, colors can be displayed without using a color filter.

5A and 5B are diagrams showing a cross section of a liquid crystal sheet when an electric field is or is not applied to the liquid crystal layer according to a third embodiment of the present invention.

As shown in FIG. 5A, when an electric field is applied between the first electrode 340 and the second electrode 350 to display an image on a liquid crystal display device, the first liquid crystal molecules contained in the core 420 of the micro tube 410 The second liquid crystal molecules 331 impregnated in the space between 421 and the micro tube 410 are arranged in the direction of the electric field. However, since the third liquid crystal molecule 443 contained in the shell 430 of the micro tube 410 polymerizes with the first monomer 441 to form the main chain liquid crystal polymer 440, the first electrode 340 and The arrangement direction of the third liquid crystal molecules 443 cannot be changed solely by the magnitude of the electric field applied between the second electrodes 350 to change the arrangement direction of the first liquid crystal molecules 421 and the second liquid crystal molecules 331. do. Accordingly, the first liquid crystal molecules 421 and the second liquid crystal molecules 331 are aligned in the direction of the electric field, and the third liquid crystal molecules 443 maintain their alignment in the direction perpendicular to the direction of the electric field, so that they are aligned with each other. There is a difference in direction. As a result, a difference in the refractive index of the first liquid crystal molecules 421, the second liquid crystal molecules 331, and the third liquid crystal molecules 443 occurs in the direction of the electric field applied to the liquid crystal layer, so that the light emitted from the backlight is transmitted through the liquid crystal layer. During the process of total reflection inside the layer 330, scattering occurs while colliding with liquid crystal molecules. Since the scattered light is emitted to the outside of the liquid crystal display device to express an image, an image can be created accordingly.

Meanwhile, as shown in Figure 5b, if the electric field is not applied between the first electrode 340 and the second electrode 350, the electric field in the original arrangement direction is applied to the first liquid crystal molecules 421 and the second liquid crystal molecules 331. They are arranged in a direction perpendicular to the direction in which they are placed. Since there is no difference in the arrangement direction of the first liquid crystal molecules 421, the second liquid crystal molecules 331, and the third liquid crystal molecules 443, the light emitted from the backlight is totally reflected inside the liquid crystal layer 330. It does not spawn. Accordingly, light reflected from an object or image located on the opposite side of the liquid crystal display device can directly pass through the liquid crystal display device, thereby displaying a transparent state. Accordingly, the third embodiment of the present invention has the effect of eliminating the need for a polarizer and a color filter to display a transparent state.

Figure 6 is a diagram showing the manufacturing process of a liquid crystal sheet according to a third embodiment of the present invention.

To manufacture the liquid crystal sheet 400 of the present invention, as shown in FIG. 6, first prepare a nozzle 500 including a first capillary 510 and a second capillary 520 surrounding the first capillary 510, and , the first liquid crystal molecule 421 is injected into the first capillary 510, and the main chain liquid crystal polymer 440 is injected into the second capillary 520. Additionally, a power supply device 600 and a rotatable collection plate 700 are prepared, and the power supply device 600 is connected to the nozzle 500 and the collection plate 700.

A voltage is applied to the nozzle 500 through the power supply 600, and the first liquid crystal molecules 421 and the main chain liquid crystal polymer 440 are emitted through the spinneret of the nozzle 500.

Since the main chain liquid crystal polymer 440 is discharged from the second capillary 520 surrounding the first capillary 510, it is arranged to have a shape similar to the circumference of a circle when looking at the spinneret of the nozzle 500. In addition, while the main chain liquid crystal polymer 440 is discharged from the spinneret of the nozzle 500, a voltage is applied, thereby electrically coupling adjacent main chain liquid crystal polymers 440. The electrically coupled main chain liquid crystal polymers 440 continue to be released, continuously forming the shell 430 of the micro tube 410 having a shape similar to the circumference of a cylinder, as shown in FIG. 4. In addition, the interior of the shell 430 made of electrically bonded main chain liquid crystal polymers 440 includes a core 420 having a shape similar to a cylinder. Since the first liquid crystal molecules 421 are released from the first capillary 510 surrounded by the second capillary 520, they are surrounded by the shell 430 made of the electrically coupled main chain liquid crystal polymer 440. Included in the core 420. In this way, the micro tubes 410 formed of the core 420 and the shell 430 are formed continuously and are collected on the rotating collection plate 700.

Since the micro tubes 410 are not gathered at a certain position on the rotating collection plate 700 but at a random position, the micro tubes 410 can be formed in a randomly entangled form. And by placing the micro tubes 410, which are continuously formed by electrospinning through the nozzle 500, on the micro tubes 410 already gathered in an entangled form on the collection plate 700, the micro tubes in an entangled form are formed. (410) can be stacked to form a liquid crystal sheet (400) having a shape similar to a non-woven fabric on the collection plate (700).

6a, 6b, and 6c show the arrangement state of the main chain liquid crystal polymers 440 inside each device, and the arrangement direction of the main chain liquid crystal polymers 440 injected into the second capillary 520 is not constant as shown in 6a. and is irregular. However, as voltage is applied to the nozzle 500 and the main chain liquid crystal polymers 440 move to the spinneret, they begin to be aligned in the direction in which they are emitted from the spinneret due to the surface tension of the nozzle 500, as shown in 6b. Thereafter, as the collection plate 700 collects and rotates the continuous main chain liquid crystal polymers 440, the main chain liquid crystal polymers 440 are arranged in the direction in which the collection plate 700 rotates, as shown in FIG. 6C. Accordingly, a micro tube 410 including a shell 430 made of main chain liquid crystal polymer 440 arranged in a certain direction can be formed. Additionally, the first liquid crystal molecule 421 may be surrounded by the main chain liquid crystal polymer 440 and arranged in the same direction as the main chain liquid crystal polymer 440. Therefore, there is no need to proceed with the process of forming an alignment film and forming an alignment direction separately for the first liquid crystal molecules 421.

The first liquid crystal molecules 421 emitted from the nozzle 500 through electrospinning and the main chain liquid crystal polymer 440 surrounding them are not collected at a certain location on the collection plate 700, but are randomly distributed on the collection plate 700. Since they are collected at the positions, the liquid crystal sheet 400 can be formed in a laminated structure in which the micro tubes 410 are entangled with each other like non-woven fabric. Accordingly, the main chain liquid crystal polymer 440 can be uniformly disposed within the liquid crystal sheet 400, which solves the problem of difficulty in uniformly forming the liquid crystal polymer inside the liquid crystal layer due to irradiation conditions or external environment during the ultraviolet irradiation process. It has a solving effect.

7A to 7D are diagrams showing the manufacturing process of the liquid crystal panel according to the third embodiment of the present invention. The liquid crystal sheet 400 of FIGS. 7A to 7D is formed by forming a micro tube 410 on the collection plate 700 of FIG. 6. The liquid crystal sheet 400, which has a form similar to a non-woven fabric formed by stacking layers in an entangled manner, is partially removed from the collection plate 700.

7A to 7D show a cross section of a liquid crystal sheet in which micro tubes are regularly arranged in a grid form for convenience of explanation, but the present invention is not limited to this and the micro tubes may be irregularly arranged within the liquid crystal sheet.

First, as shown in FIG. 7A, a first substrate 310 and a first electrode 340 are formed. Next, a thin layer of adhesive is applied on the first electrode 340, and then the liquid crystal sheet 400 is placed on the first electrode 340 and bonded together.

Thereafter, the second liquid crystal molecules 331 are applied on the liquid crystal sheet 400 bonded to the first substrate 310 as shown in FIG. 7B. The applied second liquid crystal molecules 331 permeate into every space between the micro tubes, which are empty spaces within the liquid crystal sheet 400, as shown in FIG. 7C, and the second liquid crystal molecules 331 are uniformly impregnated into the spaces between the micro tubes. is arranged in the same direction as the arrangement direction of the third liquid crystal molecules 443 included in the main chain liquid crystal polymer.

Thereafter, as shown in FIG. 7D, the second electrode 350 and the second substrate 320 are bonded on the liquid crystal sheet 400 to complete the manufacture of the liquid crystal panel.

The liquid crystal panel formed in this way has the direction of arrangement of the second liquid crystal molecules impregnated into the space between the first liquid crystal molecules included in the micro tubes in the liquid crystal sheet and the micro tubes without the need to proceed with the process of forming an alignment film, and the shell of the micro tube. It can be aligned in the same direction as the arrangement direction of the main chain liquid crystal polymer included in .

As such, the present invention is not limited to the above embodiments, and can be implemented with various changes without departing from the spirit of the present invention or impairing its effectiveness.

100, 200, 300: liquid crystal panel 110, 210, 310: first substrate
120, 220, 320: second substrate 130, 230, 330: liquid crystal layer
131, 231: liquid crystal molecule 232: liquid crystal polymer
140, 240, 340: first electrode 150, 250, 350: second electrode
160: alignment film 170: polarizer
180: Color filter layer 181, 182, 183: Red, green, blue color filter
331: second liquid crystal molecule 400: liquid crystal sheet
410: micro tube 420: core
421: first liquid crystal molecule 430: shell
440: main chain liquid crystal polymer 441: first monomer
442: second monomer 443: third liquid crystal molecule
500: nozzle 510: first capillary
520: second capillary 600: power supply device
700: Collector's Edition

Claims (12)

a liquid crystal layer;
Inside the liquid crystal layer, it includes a liquid crystal sheet including micro tubes of a core-shell structure,
The core of the micro tube contains a first liquid crystal molecule, and the shell contains a liquid crystal polymer,
The liquid crystal sheet is formed in the form of a non-woven fabric in which the micro tubes are entangled with each other,
A liquid crystal display device further comprising second liquid crystal molecules impregnated in spaces where the micro tubes of the liquid crystal sheet are spaced apart.
According to claim 1,
When an electric field is applied to the liquid crystal layer, the arrangement direction of the first liquid crystal molecules and the second liquid crystal molecules is different from the arrangement direction of the liquid crystal polymer contained in the shell of the micro tube.
According to claim 2,
When an electric field is not applied to the liquid crystal layer, the arrangement direction of the first liquid crystal molecules and the second liquid crystal molecules is the same as the arrangement direction of the liquid crystal polymer contained in the shell of the micro tube.
According to any one of claims 1 to 3,
The abnormal refractive index (n _e ) and normal refractive index (n _o ) of the first liquid crystal molecule are,
A liquid crystal display device that has the same abnormal refractive index (n _e ) and normal refractive index (n _o ) of the second liquid crystal molecule, respectively.
According to any one of claims 1 to 3,
When an electric field is not applied to the liquid crystal layer, the light emitted from the backlight is totally reflected inside the liquid crystal layer to display a transparent state,
A liquid crystal display device that displays an image by scattering light emitted from a backlight to the outside of the liquid crystal layer when an electric field is applied to the liquid crystal layer.
According to any one of claims 1 to 3,
The liquid crystal polymer contained in the shell of the micro tube includes a first monomer and a second monomer, and is formed by polymerizing the first monomer and the second monomer,
The first monomer is formed in a chain structure,
A liquid crystal display device in which the second monomer is formed of a third liquid crystal molecule.
According to claim 6,
The abnormal refractive index (n _e ) and normal refractive index (n _o ) of the third liquid crystal molecule are,
A liquid crystal display device having the same abnormal refractive index (n _e ) and normal refractive index (n _o ) of the first liquid crystal molecule, respectively.
According to any one of claims 1 to 3,
A liquid crystal display device that displays colors using a field sequential color driving method.
forming a micro tube including a core containing a first liquid crystal molecule and a shell containing a liquid crystal polymer;
Comprising the step of forming a liquid crystal sheet containing the micro tubes,
The liquid crystal sheet is formed in the form of a non-woven fabric in which the micro tubes are entangled with each other,
A method of manufacturing a liquid crystal display device further comprising the step of applying second liquid crystal molecules on the liquid crystal sheet and impregnating the spaces where the micro tubes of the liquid crystal sheet are spaced apart by the second liquid crystal molecules.
According to clause 9,
The liquid crystal sheet is,
preparing the first liquid crystal molecule in the first capillary of the nozzle and preparing the liquid crystal polymer in the second capillary of the nozzle;
applying an electric field to the nozzle to discharge the first liquid crystal molecules and the liquid crystal polymer from the nozzle, respectively;
A method of manufacturing a liquid crystal display device comprising collecting the first liquid crystal molecules and the liquid crystal polymer released while rotating a collection plate.
According to claim 9 or 10,
preparing the liquid crystal sheet including the micro tubes;
forming a first electrode on a first substrate;
adhering the liquid crystal sheet onto the first electrode;
Further comprising the step of adhering a second electrode on the liquid crystal sheet,
The step of impregnating the second liquid crystal molecules is performed between the step of adhering the liquid crystal sheet to the first electrode and the step of adhering the second electrode to the liquid crystal sheet.
According to claim 6,
A liquid crystal display device in which the first monomer is formed in a chain structure containing an alkyl group or an alkoxy group.

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