KR102501021B1 - Light controlling device and transparent display device including the same - Google Patents

Abstract

An embodiment of the present invention provides a light control device that can have a uniform light blocking rate by applying different voltages to each of the patterned lower auxiliary electrodes and a transparent display device including the same. A light control device according to an embodiment of the present invention includes a lower electrode provided on one surface of a first base film facing the second base film, an upper electrode provided on one surface of the second base film facing the first base film, and It is provided between the lower electrode and the upper electrode, and includes a liquid crystal cell including liquid crystals and ionic materials. The lower electrode includes a plurality of lower auxiliary electrodes patterned at predetermined intervals.

Description

Light control device and transparent display device including the same {LIGHT CONTROLLING DEVICE AND TRANSPARENT DISPLAY DEVICE INCLUDING THE SAME}

Embodiments of the present invention relate to a light control device and a transparent display device including the same.

As the information society develops, demands for display devices for displaying images are increasing in various forms. Accordingly, various display devices such as a liquid crystal display (LCD), a plasma display panel (PDP), and an organic light emitting display (OLED) have recently been utilized.

Display devices are becoming thinner, lighter, and lower in power consumption, and as a result, application fields of display devices are continuously increasing. In particular, the display device is used as one of the user interfaces in most electronic devices or mobile devices.

In addition, recently, research on a transparent display device that allows a user to see an object or a background located on the rear side of the display device has been actively researched. A transparent display device has advantages in space utilization, interior design, and design, and may have various application fields. The transparent display device can solve the spatial and visual limitations of existing electronic devices by implementing functions of information recognition, information processing, and information display with transparent electronic devices. For example, the transparent display device may be applied to a window of a building or a vehicle to be implemented as a smart window that shows a background or displays an image.

The transparent display device may be implemented as an organic light emitting display device, and in this case, has an advantage of low power consumption, but has a disadvantage in that the contrast ratio is lowered in a light environment, although there is no problem in the contrast ratio in a dark environment. A contrast ratio in a dark environment may be defined as a dark room contrast ratio and a contrast ratio in a light environment may be defined as a bright room contrast ratio. That is, since the transparent display device has a transmissive area to allow viewing of objects or backgrounds located on the rear side, there is a problem in that the bright-room contrast ratio is lowered. Therefore, when a transparent display device is implemented as an organic light emitting display device, a light control device capable of implementing a light-blocking mode for blocking light and a transmission mode for transmitting light is required in order to prevent the bright-room contrast ratio from deteriorating.

An embodiment of the present invention provides a light control device that can have a uniform light blocking rate by applying different voltages to each of the patterned lower auxiliary electrodes and a transparent display device including the same.

A light control device according to an embodiment of the present invention includes a first base film and a second base film facing each other, a lower electrode provided on one surface of the first base film facing the second base film, and the first base film. An upper electrode provided on one surface of the second base film facing the second base film, and a liquid crystal cell provided between the lower electrode and the upper electrode and including liquid crystals and ionic materials. The lower electrode includes a plurality of lower auxiliary electrodes patterned at predetermined intervals.

A transparent display device according to an embodiment of the present invention includes a transparent display panel that transmits light and displays an image, and a light control device disposed on at least one surface of the transparent display panel. The light control device includes a first base film and a second base film facing each other, a lower electrode provided on one surface of the first base film facing the second base film, and the second base film facing the first base film. It includes an upper electrode provided on one surface of the base film, and a liquid crystal cell provided between the lower electrode and the upper electrode and including liquid crystals and ionic materials. The lower electrode includes a plurality of lower auxiliary electrodes patterned at predetermined intervals.

An embodiment of the present invention includes a plurality of patterned lower auxiliary electrodes, and applies different voltages to each of the plurality of lower auxiliary electrodes. Accordingly, in the embodiment of the present invention, when the cell gap between the upper and lower sides of the light control device is different due to the movement of the liquid crystal cell by gravity, uniform light blocking rate is obtained by adjusting the driving voltage of the light control device. can have

In addition to the effects of the present invention mentioned above, other features and advantages of the present invention will be described below, or will be clearly understood by those skilled in the art from such description and description.

1 is a perspective view showing a transparent display device according to an embodiment of the present invention;
2 is a plan view illustrating a transparent display panel, a gate driver, a source drive IC, a flexible film, a circuit board, and a timing controller of a transparent display device according to an embodiment of the present invention;
3 is an exemplary view showing pixels of the display area of FIG. 2;
4 is a cross-sectional view taken along line II′ of FIG. 3;
5 is a perspective view showing a light control device according to an embodiment of the present invention;
6 is a plan view showing the lower electrode of FIG. 5;
7 is a cross-sectional view showing a light control device according to an example of the present invention.
8 is a perspective view showing a light control device according to another example of the present invention;
9 is a plan view showing an upper electrode of FIG. 8;
10 is a cross-sectional view showing a light control device according to another example of the present invention.

The meaning of terms described in this specification should be understood as follows.

Singular expressions should be understood to include plural expressions unless the context clearly defines otherwise, and terms such as “first” and “second” are used to distinguish one component from another, The scope of rights should not be limited by these terms. It should be understood that terms such as "comprise" or "having" do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. The term “at least one” should be understood to include all possible combinations from one or more related items. For example, "at least one of the first item, the second item, and the third item" means not only each of the first item, the second item, and the third item, but also two of the first item, the second item, and the third item. It means a combination of all items that can be presented from one or more. The term "on" is meant to include not only a case in which a component is formed directly on top of another component, but also a case in which a third component is interposed between these components.

Hereinafter, preferred examples of a light control device and a transparent display device including the light control device according to the present invention will be described in detail with reference to the accompanying drawings. In adding reference numerals to components of each drawing, the same components may have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description may be omitted.

1 is a perspective view showing a transparent display device according to an exemplary embodiment of the present invention. 2 is a plan view illustrating a transparent display panel, a gate driver, a source drive IC, a flexible film, a circuit board, and a timing controller of a transparent display device according to an exemplary embodiment of the present invention. FIG. 3 is an exemplary diagram showing pixels of the display area of FIG. 2 . FIG. 4 is a cross-sectional view taken along line II′ of FIG. 3 .

Hereinafter, a transparent display device according to an exemplary embodiment of the present invention will be described in detail with reference to FIGS. 1 to 4 . 1 to 4 , the X axis represents a direction parallel to the gate line, the Y axis represents a direction parallel to the data line, and the Z axis represents the height direction of the transparent display device.

1 to 4, a transparent display device according to an embodiment of the present invention includes a transparent display panel 100, a gate driver 120, a source drive integrated circuit (hereinafter referred to as "IC") (130 ), a flexible film 140, a circuit board 150, a timing controller 160, a light control device 200, and an adhesive layer 300.

The transparent display device according to the embodiment of the present invention has been described mainly as being implemented as an organic light emitting display (OLED), but may also be implemented as a liquid crystal display (LCD) or an electrophoresis display (ELD). can

The transparent display panel 100 includes a lower substrate 111 and an upper substrate 112 . The upper substrate 112 may be an encapsulation substrate. The lower substrate 111 is formed to be larger than the upper substrate 112 , and thus, a portion of the lower substrate 111 may be exposed without being covered by the upper substrate 112 .

Gate lines and data lines may be formed in the display area DA of the transparent display panel 100 , and light emitting units may be formed in intersection areas of the gate lines and data lines. The light emitting units of the display area DA may display an image.

As shown in FIG. 3 , the display area DA includes a transmission area TA and an emission area EA. In the transparent display panel 100, an object or a background located on the rear surface of the transparent display panel 100 can be seen through the transparent areas TA, and an image can be displayed through the light emitting areas EA. . Although FIG. 3 illustrates that the transmission area TA and the light emitting area EA are formed long in the gate line direction (X-axis direction), it is not limited thereto. That is, the transmission area TA and the light emitting area EA may be formed long in the data line direction (Y-axis direction).

The transmission area TA is an area through which incident light passes almost as it is. The light emitting area EA is an area that emits light. The light emitting area EA may include a plurality of pixels P, and each of the pixels P may include a red light emitting part RE, a green light emitting part GE, and a blue light emitting part BE, as shown in FIG. 3 . It has been exemplified to include, but is not limited thereto. For example, each of the pixels P may further include a white light emitting part in addition to the red light emitting part RE, the green light emitting part GE, and the blue light emitting part BE. Alternatively, each of the pixels P may be a red light emitting part RE, a green light emitting part GE, a blue light emitting part BE, a yellow light emitting part, a magenta light emitting part, and a cyan light emitting part. Among the parts, at least two or more light emitting parts may be included.

The red light emitting part RE is an area emitting red light, the green light emitting part GE is an area emitting green light, and the blue light emitting part BE is an area emitting blue light. The red light emitting part RE, the green light emitting part GE, and the blue light emitting part BE of the light emitting area EA emit predetermined light and correspond to non-transmitting areas that do not transmit incident light.

A transistor T, an anode electrode AND, an organic layer EL, and a cathode electrode CAT are provided in each of the red light emitting part RE, the green light emitting part GE, and the blue light emitting part BE, as shown in FIG. 4 . It can be.

The transistor T includes an active layer ACT formed on the lower substrate 111, a first insulating film I1 formed on the active layer ACT, a gate electrode GE formed on the first insulating film I1, and a gate. A second insulating film I2 provided on the electrode GE, and a source electrode provided on the second insulating film I2 and connected to the active layer ACT through the first and second contact holes CNT1 and CNT2 ( SE) and a drain electrode DE. Although FIG. 4 illustrates that the transistor T is formed in a top gate method, it is not limited thereto, and the gate electrode GE may be formed in a bottom gate method in which the gate electrode GE is disposed under the active layer ACT.

The anode electrode AND is connected to the drain electrode DE of the transistor T through the third contact hole CNT3 penetrating the interlayer insulating film ILD provided on the source electrode SE and the drain electrode DE. . A bank B is provided between adjacent anode electrodes AND, so that the adjacent anode electrodes AND can be electrically insulated from each other.

An organic layer EL is provided on the anode electrode AND. The organic layer EL may include a hole transporting layer, an organic light emitting layer, and an electron transporting layer. A cathode electrode CAT is provided on the organic layer EL and the barrier rib B. When voltage is applied to the anode electrode AND and the cathode electrode CAT, holes and electrons move to the organic light emitting layer through the hole transport layer and the electron transport layer, respectively, and combine with each other in the organic light emitting layer to emit light.

In FIG. 4 , the transparent display panel 100 is embodied in a top emission method, but is not limited thereto and may be implemented in a bottom emission method. In the top emission method, since the organic layer EL emits light toward the upper substrate, the transistor T can be widely provided under the bank B and the anode AND. Accordingly, the top emission method has an advantage in that the design area of the transistor T is wider than that of the bottom emission method. In the top emission method, it is preferable that the anode electrode AND is formed of a highly reflective metal material such as aluminum or a laminated structure of aluminum and ITO, and the cathode electrode CAT is formed of a transparent metal material such as ITO or IZO.

As described above, each of the pixels P of the transparent display device according to the exemplary embodiment of the present invention includes a transmission area TA that passes incident light almost as it is and an emission area EA that emits light. . As a result, in the embodiment of the present invention, an object or a background located on the rear surface of the transparent display device can be viewed through the transparent areas TA of the transparent display device.

The gate driver 120 supplies gate signals to the gate lines according to the gate control signal input from the timing controller 160. 2 illustrates that the gate driver 120 is formed outside one side of the display area DA of the transparent display panel 100 by a gate driver in panel (GIP) method, but is not limited thereto. That is, the gate driver 120 may be formed on the outside of both sides of the display area DA of the transparent display panel 100 by the GIP method, or may be manufactured as a driving chip and mounted on a flexible film and used for tape automated bonding (TAB). It may also be attached to the transparent display panel 100 in this way.

The source drive IC 130 receives digital video data and a source control signal from the timing controller 160 . The source driver IC 130 converts digital video data into analog data voltages according to a source control signal and supplies them to data lines. When the source drive IC 130 is manufactured as a driving chip, it may be mounted on the flexible film 140 in a chip on film (COF) or chip on plastic (COP) method.

Since the size of the lower substrate 111 is greater than that of the upper substrate 112 , a portion of the lower substrate 111 may be exposed without being covered by the upper substrate 112 . Pads, such as data pads, are provided on a portion of the lower substrate 111 that is exposed and not covered by the upper substrate 112 . Wires connecting pads and the source drive IC 130 and wires connecting pads and wires of the circuit board 150 may be formed on the flexible film 140 . The flexible film 140 is attached to the pads using an anisotropic conducting film, and thereby the pads and the wires of the flexible film 140 can be connected.

The circuit board 150 may be attached to the flexible films 140 . A plurality of circuits implemented as driving chips may be mounted on the circuit board 150 . For example, the timing controller 160 may be mounted on the circuit board 150 . The circuit board 150 may be a printed circuit board or a flexible printed circuit board.

The timing controller 160 receives digital video data and timing signals from an external system board (not shown). The timing controller 60 generates a gate control signal for controlling the operation timing of the gate driver 120 and a source control signal for controlling the source drive ICs 130 based on the timing signal. The timing controller 60 supplies a gate control signal to the gate driver 120 and supplies a source control signal to the source drive ICs 30 .

The light control device 200 may block incident light in a light blocking mode and transmit incident light in a transmission mode. The light control device 200 blocks most of the light in the light blocking mode, and may be designed, for example, so that the ratio of incident light to output light (hereinafter referred to as “light transmittance”) is α% or less. In addition, the light control device 200 transmits most of the light in a transmission mode, and may be designed to have a light transmittance of, for example, β% or more. At this time, β is greater than α. The light control device 200 according to an embodiment of the present invention may implement a light blocking mode and a transmission mode using a liquid crystal layer to which a dynamic scattering mode is applied. A detailed description of the light control device 200 according to an embodiment of the present invention will be described later with reference to FIGS. 5 to 10 .

The adhesive layer 300 bonds the transparent display panel 100 and the light control device 200 together. The adhesive layer 300 may be a transparent adhesive film such as optically clear adhesive (OCA) or a transparent adhesive such as optically clear resin (OCR). In this case, the adhesive layer 300 may have a refractive index between 1.4 and 1.9 to match the refractive index between the transparent display panel 100 and the light control device 200 .

5 is a perspective view showing a light control device according to an example of the present invention. FIG. 6 is a plan view showing the lower electrode of FIG. 5 . 7 is a cross-sectional view showing a light control device according to an embodiment of the present invention.

5 to 7 , the light control device 200 according to an embodiment of the present invention includes a first base film 210, a second base film 220, a lower electrode 230, and an upper electrode 240. , a liquid crystal layer 250 and a spacer 252 .

The first base film 210 and the second base film 220 may be plastic films. For example, the first base film 210 and the second base film 220 may include a cellulose resin such as triacetyl cellulose (TAC) or diacetyl cellulose (DAC), or a cyclo olefin (COP) such as norbornene derivatives. polymer), COC (cyclo olefin copolymer), PMMA (poly (methylmethacrylate), etc. acrylic resin, PC (polycarbonate), PE (polyethylene) or PP (polypropylene), polyolefin (PVA (polyvinyl alcohol), PES ( Polyester such as poly ether sulfone), PEEK (polyetheretherketone), PEI (polyetherimide), PEN (polyethylenenaphthalate), PET (polyethyleneterephthalate), PI (polyimide), PSF (polysulfone), or fluoride resin, etc. It may be a sheet or film containing, but is not limited thereto.

The lower electrode 230 is provided on one surface of the first base film 210 facing the second base film 220 . The lower electrode 230 includes a plurality of lower auxiliary electrodes 231 to 234 . Each of the plurality of auxiliary lower electrodes 231 to 234 is patterned on the first base film 210 at predetermined intervals. Each of the plurality of lower auxiliary electrodes 231 to 234 may be disposed side by side in the Y-axis direction. Different voltages V1 to V4 may be applied to each of the plurality of auxiliary lower electrodes 231 to 234 . Each of the plurality of lower auxiliary electrodes 231 to 234 may have a stripe shape, but is not limited thereto.

Specifically, the lower electrode 230 may include first to fourth auxiliary lower electrodes 231 to 234 . Each of the first to fourth auxiliary lower electrodes 231 to 234 may be transparent electrodes patterned on the first base film 210 at predetermined intervals. When the light control device 200 is erected vertically (Y-axis direction), the first to fourth lower auxiliary electrodes 231 to 234 move from the upper side 200a to the lower side 200b of the light control device 200. Can be arranged sequentially. That is, the first auxiliary lower electrode 231 may be disposed on the upper side 200a of the light control device 200, and the fourth auxiliary lower electrode 234 may be disposed on the lower side 200b.

First to fourth voltages V1 to V4 may be applied to each of the first to fourth lower auxiliary electrodes 231 to 234 . A first voltage V1 may be applied to the first lower auxiliary electrode 231 , and a second voltage V2 may be applied to the second lower auxiliary electrode 232 . A third voltage V3 may be applied to the third auxiliary lower electrode 233 , and a fourth voltage V4 may be applied to the fourth auxiliary lower electrode 234 . In this case, the first voltage V1 is greater than the second voltage V2, the second voltage V2 is greater than the third voltage V3, and the third voltage V3 is greater than the fourth voltage V4. can (V1> V2> V3> V4) That is, when the light control device 200 is erected vertically (Y-axis direction), the first lower auxiliary electrode disposed at the highest position among the plurality of lower auxiliary electrodes 231 to 234 The highest first voltage V1 may be applied to the electrode 231 . Also, the lowest fourth voltage V4 may be applied to the fourth lower auxiliary electrode 234 disposed at the lowest position.

The upper electrode 240 is provided on one surface of the second base film 220 facing the first base film 210 . The upper electrode 240 may be a transparent electrode. In this case, a voltage different from the voltages V1 to V4 applied to each of the plurality of auxiliary lower electrodes 231 to 234 may be applied to the upper electrode 240 .

The lower electrode 230 and the upper electrode 240 may include, for example, oxide (eg AgO or Ag2O or Ag2O3), aluminum oxide (eg Al2O3), tungsten oxide (eg WO2 or WO3 or W2O3), magnesium oxide ( eg MgO), molybdenum oxide (eg MoO3), zinc oxide (eg ZnO), tin oxide (eg SnO2), indium oxide (eg In2O3), chromium oxide (eg CrO3 or Cr2O3), antimony oxide ( eg Sb2O3 or Sb2O5), titanium oxide (eg TiO2), nickel oxide (eg NiO), copper oxide (eg CuO or Cu2O), vanadium oxide (eg V2O3 or V2O5), cobalt oxide (eg CoO) , iron oxide (eg Fe2O3 or Fe3O4), niobium oxide (eg Nb2O5), indium tin oxide (eg Indium Tin Oxide, ITO), indium zinc oxide (eg Indium Zinc Oxide, IZO), aluminum doped zinc oxide (eg, Aluminum doped Zinc Oxide, ZAO), aluminum doped tin oxide (eg, Aluminum Tin Oxide, TAO), or antimony tin oxide (eg, Antimony Tin Oxide, ATO), but is not limited thereto.

A conventional light control device implements a light blocking mode by applying different voltages to the lower electrode and the upper electrode without patterning the lower electrode. When such a conventional light control device is driven for a long time in a vertical state, a gravity defect phenomenon in which the liquid crystal cells 251 are concentrated from the upper side 200a to the lower side 200b by gravity may occur. When the liquid crystal cells 251 are concentrated on the lower side 200b, a cell gap of the light control device may increase from the upper side to the lower side. Accordingly, the light control device may have a non-uniform light blocking rate.

However, in one example of the present invention, the lower electrode 230 is patterned to provide a plurality of lower auxiliary electrodes 231 to 234, and each of the plurality of lower auxiliary electrodes 231 to 234 has different voltages (V1). to V4) are applied. Accordingly, the light control device 200 is driven for a long time in a vertical state, and the movement of the liquid crystal cell due to gravity causes a cell gap between the upper side 200a and the lower side 200b of the light control device 200. ) is changed, it is possible to have a uniform light blocking rate by adjusting the driving voltage of the light control device 200 according to the position.

Specifically, when the light control device 200 is erected vertically (Y-axis direction), the liquid crystal cells 251 may be concentrated in the lower direction 200b due to gravity. Accordingly, the cell gap may increase toward the lower side 200b compared to the upper side 200a.

In an example of the present invention, the first voltage V1 is applied to the first lower auxiliary electrode 231 positioned on the upper side 200a having a relatively small cell gap. Further, a fourth voltage V4 lower than the first voltage V1 is applied to the fourth lower auxiliary electrode 234 positioned on the lower side 200b having a relatively large cell gap. Accordingly, an example of the present invention may have a uniform light blocking rate for each location.

In one example of the present invention, the present invention has been described by taking four lower auxiliary electrodes as an example, but is not limited thereto. That is, at least two or more lower auxiliary electrodes may be provided on the first base film 210 . In addition, in one example of the present invention, the present invention has been described by taking patterning of only the lower electrode as an example, but it is not limited thereto, and it is also possible to pattern only the upper electrode.

The liquid crystal layer 250 is provided between the lower electrode 230 and the upper electrode 240 . The liquid crystal layer 250 may be a dynamic scattering mode liquid cyrstal layer including liquid crystals, dichroic dyes, and ionic materials. In the case of the dynamic scattering mode, when a voltage is applied to the lower electrode 230 and the upper electrode 240, liquid crystals and dichroic dyes are randomly moved by ionic materials. In this case, since light incident on the liquid crystal layer 250 may be scattered by randomly moving liquid crystals or absorbed by dichroic dyes, a light blocking mode may be realized.

Specifically, the liquid crystal layer 250 may include liquid crystal cells 251 , a first alignment layer 253 and a second alignment layer 254 . The liquid crystal cells 251 are provided between the lower electrode 230 and the upper electrode 240 . The liquid crystal cells 251 include liquid crystals 251a, dichroic dyes 251b, and ionic materials 251c.

The long axis direction of the liquid crystals 251a may be aligned in the vertical direction (Z-axis direction) by the first and second alignment layers 253 and 254 even if no voltage is applied to the lower and upper electrodes 230 and 240. . The long axis direction of the dichroic dyes 251b is also the vertical direction (Z) by the first and second alignment layers 253 and 254 even if no voltage is applied to the lower and upper electrodes 230 and 240 like the liquid crystals 251a. axial direction). As a result, since the liquid crystals 251a and the dichroic dye 251b are arranged in a direction in which light is incident, scattering and absorption of light due to the liquid crystals 251a and the dichroic dye 251b are minimized. That is, since the long axes of the liquid crystals 251a are arranged in a vertical direction (Z-axis direction), light incident to the light control device passes through the long axes of the liquid crystals 251a. In this case, since the long axes of the liquid crystals 251a all have the same refractive index, scattering of light passing through the liquid crystals 251a is minimized. Therefore, most of the light incident on the light control device 200 may pass through the liquid crystal cells 251 . Therefore, since the light control device 200 can operate in a transmission mode even when no voltage is applied, the transmission mode can be implemented without power consumption.

The dichroic dyes 251b may be dyes that absorb light. For example, the dichroic dyes 251b may be a black dye that absorbs all light in a visible ray wavelength range or a specific color (eg, red) that absorbs light other than a wavelength range and a specific color (eg, red). ) may be a dye that reflects light in the wavelength range. In the embodiment of the present invention, it has been mainly described that the dichroic dyes 251b are black dyes, but it is not limited thereto. For example, the dichroic dyes 251b may be dyes having a color of any one of red, green, blue, and yellow, or a mixture thereof. there is. That is, the embodiment of the present invention can block the background while expressing various colors in the light blocking mode. Due to this, since the embodiment of the present invention can provide various colors in the light blocking mode, the user can feel the aesthetic sense. For example, the transparent display device according to an embodiment of the present invention can be used in a public place, and when applied to a smart window or public window requiring a transmission mode and a shading mode, various colors are expressed depending on time or place. You can shade while doing it.

The ionic materials 251c serve to randomly move the first and second liquid crystals 251a and 251d and the dichroic dye 251b. The ionic materials 251c may have a predetermined polarity, and thus, in the light blocking mode, the ionic materials 251c are directed toward the lower electrode 230 or the upper electrode 240 according to polarities of voltages applied to the lower electrode 230 and the upper electrode 240. can move For example, when the ionic materials 251c have a negative polarity, when a positive voltage is applied to the lower electrode 230 and a negative voltage is applied to the upper electrode 240, the ionic materials 251c are formed at the lower electrode ( 230). In addition, when the ionic materials 251c have a negative polarity, when a positive voltage is applied to the upper electrode 240 and a negative voltage is applied to the lower electrode 230, the ionic materials 251c form the upper electrode 240. go to In addition, when the ionic materials 251c have a positive polarity, when a positive voltage is applied to the lower electrode 230 and a negative voltage is applied to the upper electrode 240, the ionic materials 251c form the upper electrode 240. go to In addition, when the ionic materials 251c have a positive polarity, when a positive voltage is applied to the upper electrode 240 and a negative voltage is applied to the lower electrode 230, the ionic materials 251c form the lower electrode 230. go to Therefore, when a voltage is applied to the lower and upper electrodes 230 and 240, the ionic materials 251c go from the lower electrode 230 to the upper electrode 240 at a predetermined cycle and then return to the lower electrode 230 again. move is repeated. In this case, since the ionic materials 251c collide with the liquid crystals 251a and the dichroic dyes 251b while moving, the liquid crystals 251a and the dichroic dyes 251b move randomly. Here, the voltage applied to the lower and upper electrodes 230 and 240 may be an AC voltage.

Alternatively, the ionic materials 251c may exchange electrons with each other according to polarities of voltages applied to the lower electrode 230 and the upper electrode 240 . Therefore, when an AC voltage having a predetermined period is applied to the lower and upper electrodes 230 and 240, the ionic materials 251c exchange electrons at a predetermined period. In this case, since the electrons collide with the liquid crystals 251a and the dichroic dyes 251b while moving, the liquid crystals 251a and the dichroic dyes 251b may move randomly. Alternatively, since the electrons change or distort the vertical electric field while moving, the liquid crystals 251a and the dichroic dyes 251b may move randomly due to the change or distortion of the vertical electric field.

Since the liquid crystal cell 251 is in a liquid state, spacers 252 may be provided to maintain a cell gap of the liquid crystal cell 251 . The spacers 252 may be disposed on one surface of the lower electrode 230 facing the second base film 220 . The spacers 252 may be spaced apart at predetermined intervals.

The spacers 252 are for maintaining a cell gap of the liquid crystal layer 250 . Since the spacers 252 are provided, the inside of the liquid crystal layer 250 can be protected when force is applied from the outside. The spacers 252 may be formed of a transparent material. In this case, the spacers 252 may be formed of any one of photo resist, photocurable polymer, and polydimethylsiloxane, but are not limited thereto.

Alternatively, the spacers 252 may include a material capable of absorbing light. For example, each of the spacers 252 may be implemented in black. In this case, since the spacers 252 can absorb light scattered by the liquid crystals 251a in the light blocking mode, the light blocking rate in the light blocking mode can be increased. In addition, since the spacers 252 are provided to correspond to the light emitting area EA of the transparent display panel 100 in the embodiment of the present invention, even if each of the spacers 252 is implemented in black, the transmittance is hardly lost in the transmission mode. don't

Alternatively, the spacers 252 may include scattering particles capable of scattering light. The scattering particles may be beads or silica balls. In this case, since the spacers 252 may re-scatter light scattered by the liquid crystals 251a in the light blocking mode, an optical path may be lengthened. Since the probability of light being absorbed by the dichroic dyes 251b increases when the optical path becomes longer, the light blocking rate in the light blocking mode may be increased.

Meanwhile, the spacers 252 do not actively pass light or block light like the liquid crystal cells 251 do. That is, when the spacers 252 are made of a transparent material, they pass light and do not block light. In addition, when the spacers 252 include a material that absorbs light or a material that scatters light, they only scatter or block light and do not pass light. Therefore, when the spacers 252 are formed in an area corresponding to the transmissive area TA of the transparent display device, light leakage occurs in the spacers 252 in the light-shielding mode, resulting in increased light transmittance, or the spacers 252 in the transmissive mode. ), there is a problem that light transmittance is lowered by blocking light. Accordingly, the spacers 252 are disposed to correspond to the emission areas EA of the transparent display panel 100, and the liquid crystal cells 251 are disposed to correspond to the transmission areas TA of the transparent display panel 100. it is desirable The spacers 252 may have a ball shape, but are not necessarily limited thereto.

The first alignment layer 253 is provided on one surface of the lower electrode 230 facing the second base film 220 . The first alignment layer 253 is provided on one surface of the first to fourth lower auxiliary electrodes 231 to 234 . The first alignment layer 253 surrounds the spacer 252 and is provided on one surface of the spacer 252 . The second alignment layer 254 is provided on one surface of the upper electrode 240 facing the first base film 210 . When no voltage is applied to the lower and upper electrodes 230 and 240, the first and second alignment layers 253 and 254 direct the major axes of the liquid crystals 251a and the dichroic dyes 251b in the vertical direction (Z). axial direction) may be vertical alignment layers for arranging.

As described above, the light control device 200 according to an example of the present invention does not apply voltage to the lower and upper electrodes 230 and 240 in the transmission mode, and thus the first and second alignment layers ( 253 and 254 may align the major axes of the liquid crystals 251a and the dichroic dyes 251b in a vertical direction (Z-axis direction). As a result, since the liquid crystal 251a and the dichroic dye 251b are arranged in a direction in which light is incident, light scattering and absorption due to the liquid crystal 251a and the dichroic dye 251b are minimized. Therefore, most of the light incident on the light control device 200 may pass through the liquid crystal cells 251 .

In addition, the light control device 200 according to an example of the present invention applies a voltage to the lower and upper electrodes 230 and 240 in a light blocking mode, and in this case, the liquid crystals 251a are formed by the ionic materials 251c. And the dichroic dyes 251b may be randomly moved. As a result, since light is scattered by the liquid crystals 251a of the liquid crystal cells 251 or absorbed by the dichroic dyes 251b, most of the light incident on the light control device 200 is the liquid crystal cell ( 251) can be blocked.

In addition, the light control device 200 according to an embodiment of the present invention includes a plurality of patterned auxiliary lower electrodes 231 to 234, and different voltages are applied to each of the plurality of auxiliary lower electrodes 231 to 234. is authorized As a result, since the liquid crystal cells are moved by gravity, even if a difference occurs in the cell gap between the lower electrode and the upper electrode, a uniform light blocking rate can be obtained.

8 is a perspective view showing a light control device according to another example of the present invention. FIG. 9 is a plan view showing only the upper electrode of FIG. 8 . 10 is a cross-sectional view showing a light control device according to another example of the present invention. Another example of the present invention is the same as the example of the present invention described with reference to FIGS. 5 to 7 except that the upper electrode 240 includes a plurality of patterned upper auxiliary electrodes 241 to 244. . Therefore, the same reference numerals are assigned to the same components, and redundant descriptions of repetitive parts in the materials and structures of each component are omitted.

Referring to FIGS. 8 to 10 , a lower electrode 230 according to another example of the present invention may include first to fourth auxiliary lower electrodes 231 to 234 . First to fourth voltages V1 to V4 may be applied to each of the first to fourth lower auxiliary electrodes 231 to 234 . In this case, the first voltage V1 is greater than the second voltage V2, the second voltage V2 is greater than the third voltage V3, and the third voltage V3 is greater than the fourth voltage V4. can (V1 > V2 > V3 > V4)

The upper electrode 240 according to another example of the present invention is provided on one surface of the second base film 220 facing the first base film 210 . The upper electrode 240 includes a plurality of upper auxiliary electrodes 241 to 244 . Each of the plurality of auxiliary upper electrodes 241 to 244 is patterned on the second base film 220 at predetermined intervals. Each of the plurality of upper auxiliary electrodes 241 to 244 may be disposed side by side in the Y-axis direction. Each of the plurality of upper auxiliary electrodes 241 to 244 may have a stripe shape, but is not limited thereto. Each of the plurality of auxiliary upper electrodes 241 to 244 is provided at a position corresponding to each of the plurality of auxiliary lower electrodes 231 to 234 . Each of the plurality of auxiliary upper electrodes 241 to 244 is disposed to face each of the plurality of auxiliary lower electrodes 231 to 234 . Different voltages V6 to V9 may be applied to each of the plurality of auxiliary upper electrodes 241 to 244 . However, it is not limited thereto and the same voltages may be applied.

Specifically, the upper electrode 240 may include first to fourth upper auxiliary electrodes 241 to 244 . Each of the first to fourth auxiliary upper electrodes 241 to 244 may be transparent electrodes patterned on the second base film 240 at predetermined intervals. When the light control device 200 is erected vertically (in the Y-axis direction), the first to fourth upper auxiliary electrodes 241 to 244, like the first to fourth lower auxiliary electrodes 231 to 234, the light It may be sequentially arranged from the upper side 200a to the lower side 200b of the control device 200 . That is, the first auxiliary upper electrode 241 may be disposed on the upper side 200a of the light control device 200, and the fourth upper auxiliary electrode 244 may be disposed on the lower side 200b.

Sixth to ninth voltages V6 to V9 may be applied to the first to fourth upper auxiliary electrodes 241 to 244 , respectively. A sixth voltage V6 may be applied to the first auxiliary upper electrode 241 , and a seventh voltage V7 may be applied to the second auxiliary upper electrode 242 . An eighth voltage V8 may be applied to the third auxiliary upper electrode 243 , and a ninth voltage V9 may be applied to the fourth auxiliary upper electrode 244 . In this case, the sixth voltage V6 is less than the seventh voltage V7, the seventh voltage V7 is less than the eighth voltage V8, and the eighth voltage V8 is less than the ninth voltage V9. can be small (V6 < V7 < V8 < V9) That is, when the light control device 200 is erected vertically (Y-axis direction), the first upper auxiliary electrode disposed at the highest position among the plurality of upper auxiliary electrodes 241 to 244 A sixth voltage V6 may be applied to the electrode 241 . Also, a ninth voltage V9 higher than the sixth voltage V6 may be applied to the fourth upper auxiliary electrode 244 disposed at the lowest position.

Another example of the present invention increases the voltage difference between the first auxiliary lower electrode 231 and the first auxiliary upper electrode 241 located on the upper side 200a, and the fourth lower auxiliary electrode 234 located on the lower side 200b And by lowering the voltage difference between the fourth upper auxiliary electrode 244, it is possible to have a uniform light transmittance for each position.

In another example of the present invention, the present invention has been described by taking four upper auxiliary electrodes as an example, but is not limited thereto. That is, at least two or more patterned auxiliary electrodes may be provided on the second base film 220 .

The light control device 200 according to another example of the present invention provides the same effect as the example of the present invention. That is, in another example of the present invention, a plurality of lower auxiliary electrodes 231 to 234 are provided by patterning the lower electrode 230, and different voltages V1 are applied to the plurality of auxiliary lower electrodes 231 to 234, respectively. to V4) are applied. In addition, the upper electrode 230 is patterned to provide a plurality of auxiliary upper electrodes 241 to 244 facing the plurality of auxiliary lower electrodes 231 to 234, and a plurality of auxiliary upper electrodes 241 to 244 Different voltages V6 to V9 are applied to each. Accordingly, even when the cell gap between the upper side 200a and the lower side 200b of the light control device 200 is different due to the movement of the liquid crystal cell by gravity, the light control device 200 depending on the position It is possible to have a uniform light blocking rate by adjusting the driving voltage of .

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and it is common in the technical field to which the present invention belongs that various substitutions, modifications, and changes are possible without departing from the technical details of the present invention. It will be clear to those who have knowledge of Therefore, the scope of the present invention is indicated by the following claims, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts should be construed as being included in the scope of the present invention.

100: transparent display panel
111: lower substrate 112: upper substrate
120: gate driver 130: source drive IC
140: flexible film 150: circuit board
160: timing controller 200: light controller
210: first base film 220: second base film
230: lower electrode 240: upper electrode
250: liquid crystal layer 251: liquid crystal cell
251a: liquid crystal 251b: dichroic dye
251c: ionic material 252: spacer
253: first alignment layer 254: second alignment layer
300: adhesive layer

Claims (10)

a first base film and a second base film facing each other;
a lower electrode provided on one surface of the first base film facing the second base film;
an upper electrode provided on one surface of the second base film facing the first base film;
a liquid crystal cell provided between the lower electrode and the upper electrode and containing liquid crystals and ionic materials;
spacers for maintaining a cell gap of the liquid crystal cell;
a plurality of first regions having a light blocking mode or a transmission mode by the liquid crystal cell; and
a second region between the plurality of first regions and having the spacers;
The light control device of claim 1 , wherein the lower electrode includes a plurality of lower auxiliary electrodes patterned at predetermined intervals. According to claim 1,
The plurality of lower auxiliary electrodes are composed of first to fourth lower auxiliary electrodes disposed side by side,
The light control device of claim 1 , wherein different voltages are applied to each of the first to fourth auxiliary lower electrodes. According to claim 2,
A voltage applied to the first auxiliary lower electrode is greater than a voltage applied to the second auxiliary lower electrode, a voltage applied to the second auxiliary lower electrode is greater than a voltage applied to the third auxiliary lower electrode, and 3 A light control device in which a voltage applied to the lower auxiliary electrode is greater than a voltage applied to the fourth auxiliary lower electrode. According to claim 1,
The light control device of claim 1 , wherein a voltage different from a voltage applied to each of the plurality of lower auxiliary electrodes is applied to the upper electrode. According to claim 2,
The upper electrode includes first to fourth upper auxiliary electrodes patterned at predetermined intervals;
The light control device of claim 1 , wherein each of the first to fourth auxiliary upper electrodes is disposed to correspond to each of the first to fourth auxiliary lower electrodes. According to claim 5,
A light control device in which different voltages are applied to each of the first to fourth auxiliary upper electrodes. delete According to claim 1,
a first alignment layer provided on one surface of the lower electrode; and
Further comprising a second alignment layer provided on one surface of the upper electrode facing the lower electrode,
The first and second alignment layers align the liquid crystals in a vertical direction when no voltage is applied to the lower and upper electrodes. According to claim 1,
Each of the liquid crystal cells further includes dichroic dyes that absorb light,
The ionic materials move the liquid crystals and dichroic dyes when voltages are applied to the lower and upper electrodes. a transparent display panel that transmits light and displays an image; and
A transparent display device comprising the light control device according to any one of claims 1 to 6, 8 and 9, disposed on at least one side of the transparent display panel.

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