Variable transparency glass and device for controlling its transmittance

Abstract

The present invention relates to variable transparency glass and a device for controlling the transmittance thereof. A variable transparency glass comprises: a first film having a first transparent electrode on an inner surface of the first film; a second film having a second transparent electrode on an inner surface of the second film; and a liquid crystal capsule disposed between the first film and the second film. The variable transparency glass is configured to control the transmittance of incident light in response to a voltage applied to each of the first transparent electrode and the second transparent electrode. When the first film and the second film overlap, the transmittance corresponding to an alignment pattern of each of the first transparent electrode and the second transparent electrode is partially controlled.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the priority of Korean Patent Application No. 10-2019-0082655 filed on July 9, 2019, in the Korean Intellectual Property Office, which is incorporated herein by reference. Technical Field

[0003] The invention relates to variable transparency glass and a device for controlling the same. Background Art

[0004] A variable transparency switching window (VTSW) applied to a front glass, a sunroof, etc. of a vehicle can switch transmittance in response to each transparency. Therefore, a device for controlling transmittance is designed to provide transparency according to a user's selection.

[0005] Generally, variable transparency glass includes a transmission layer capable of changing light transmittance and optical properties in response to power applied to power electrode terminals through two power electrodes. In order to make the transmission layer have the above properties, the variable transparency glass includes a transmission layer mainly including a liquid polymer.

[0006] Recently, the above-mentioned variable transparency glass has been applied to the glass of the vehicle, and thus, the transparency of the vehicle glass can be switched based on the user's selection. In addition, when the head-up display is applied to the vehicle, adjusting the transparency of the front glass of the vehicle is an indispensable element.

[0007] Meanwhile, in the variable transparency glass having the above configuration, it is difficult to adjust the transparency based on the user's selection. In addition, when manufacturing a transparency-adjusting glass in which the transmission layer is formed to have a gas structure, the gas density is not balanced and an additional circuit for driving the gas structure is required. Summary of the invention

[0008] The present invention relates to a variable transparency glass and a control device thereof. In a specific embodiment, the present invention relates to a glass capable of variably controlling the transmittance of incident light.

[0009] The embodiments of the present invention can solve the problems in the prior art while maintaining the advantages achieved by the prior art.

[0010] One aspect of the present disclosure provides a variable transparency glass capable of adjusting transparency and selectively adjusting a specific portion of the glass based on user's needs and environment, and an apparatus for controlling transparency thereof.

[0011] The technical problems to be solved by the present invention are not limited to the above problems, and those skilled in the art to which the present disclosure belongs will clearly understand any other technical problems not mentioned herein from the following description.

[0012] According to one aspect of the present disclosure, a variable transparency glass includes: a first film having a first transparent electrode on an inner surface of the first film; a second film having a second transparent electrode on an inner surface of the second film; and a liquid crystal capsule disposed between the first film and the second film and controlling the transmittance of incident light in response to a voltage applied to each of the first transparent electrode and the second transparent electrode. When the first film and the second film overlap, the transmittance of an alignment pattern corresponding to each of the first transparent electrode and the second transparent electrode is partially controlled.

[0013] According to another aspect of the present invention, a device for controlling variable transparency glass includes: glass that variably controls transmittance according to a voltage; a voltage controller that supplies the voltage to the variable transparency glass; and a controller that selects a transmittance mode in response to input information and controls the level of the voltage based on the selected transmittance mode. The transparent glass includes: a first film having a first transparent electrode on an inner surface of the first film; a second film having a second transparent electrode on an inner surface of the second film; and a liquid crystal capsule that is disposed between the second film and the second film and variably controls the transmittance of incident light in response to a voltage applied to each of the first transparent electrode and the second transparent electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and other objects, features and advantages of the present disclosure will become more apparent through the following detailed description in conjunction with the accompanying drawings:

[0015] Figure 1 is a view illustrating a concept of a variable transparency glass according to an embodiment of the present disclosure;

[0016] Figure 2 is a block diagram of an apparatus for controlling variable transparency glass according to an embodiment of the present disclosure;

[0017] Figure 3 is a detailed structural diagram of a variable transparency glass according to an embodiment of the present disclosure;

[0018] Figure 4 and Figure 5 yes Figure 3 A cross-sectional view of a variable transparency glass;

[0019] Figure 6 Show Figure 5 Embodiment of the variable transmission layer of the liquid crystal capsule;

[0020] Fig. 7A and Figure 7B It is used to illustrate Figure 3 A view of a patterned structure of a variable transparency glass;

[0021] Figure 8 It is used to illustrate Figure 3 A view of the partial transmittance of a variable transparency glass;

[0022] Fig. 9 and Fig.10 A view for showing a transparent mode and a non-transparent mode depending on a transmittance switch

[0023] Fig.11 It is used to illustrate Figure 3 A diagram showing the linear control level of transmittance of a variable transparency glass;

[0024] Fig.12 yes Figure 2 Block diagram of the voltage controller;

[0025] Fig.13 Yes Description Fig.12 A waveform diagram of a control method of a voltage controller; and

[0026] Fig.14 is a flow chart illustrating a method of controlling a variable transparency glass according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It should be noted that when adding reference numerals to constituent elements of the accompanying drawings, even if the same constituent elements are shown in different drawings, the same constituent elements are represented by the same reference numerals as much as possible. In addition, in the following description of embodiments of the present disclosure, when it is not a decisive difference that the embodiments of the present disclosure can be incorporated, the detailed description of the known functions and configurations incorporated herein will be omitted.

[0028] Figure 1 2 is a view illustrating a concept of a variable transparency glass according to an embodiment of the present disclosure.

[0029] refer to Figure 1 , the embodiment of the present disclosure can use the variable transparency glass 10 in the form of a smart window film to control the difference in transmittance and refractive index in response to an electric field reaction. The variable transparency glass 10 is cut according to the shape of the vehicle glass or the shape of the object using the smart window film and is molded for installation.

[0030] The variable transparency glass 10 can variably control the transmittance of a vehicle window. When the variable transparency glass 10 is applied to a vehicle, the safety and convenience of the vehicle can be improved.

[0031] As the functions of vehicles gradually develop and meet the future age of autonomous driving, the value of vehicles can be used as living spaces rather than just transportation. To this end, the variable transparency glass 10 according to the embodiment of the present disclosure can be applied to autonomous driving vehicles. Here, a private area can be formed, and the occupants can be protected from external environments such as ultraviolet rays, infrared rays, excessive temperature changes, etc.

[0032] Figure 2 is a block diagram of an apparatus for controlling variable transparency glass according to an embodiment of the present disclosure.

[0033] refer to Figure 2 , an apparatus for controlling a variable transparency glass according to an embodiment of the present disclosure includes a variable transparency glass 10 , a voltage controller 20 , a controller 30 , and a memory 40 .

[0034] Here, the variable transparency glass 10 has a thin film structure in which a transparent electrode film is deposited and rubbed. The variable transparency glass 10 can switch transmittance and can control the change of the low refractive index. The variable transparency glass 10 has light transmittance and variably controls the light transmittance based on a voltage source applied to an internal transparent electrode, and the light transmittance depends on the change of the electric field formed between the internal transparent electrodes.

[0035] The variable transparency glass 10 switches the transmittance of each window manually or automatically using a separate switch operation, integrated control of a display device of the vehicle (e.g., a navigation terminal and audio video navigation (AVN)), control of a user interface (UI), or a smartphone application (Bluelink, etc.). The transmittance of the variable transparency glass 10 can be changed based on a user control mode or an automatic transmittance control mode to provide an optimal window transmittance in the driving environment of the vehicle.

[0036] In addition, the voltage controller 20 is controlled by the controller 30 and provides a linear voltage to the transparent electrode of the variable transparency glass 10. The voltage controller 20 uses a converter including a switching device (such as a MOSFET) to reduce or increase the voltage. Therefore, the linear voltage is provided to the variable transparency glass 10. In addition, the voltage controller 20 blocks the voltage output when turned off, ramps the adjustable soft start current, and limits the foldback output current.

[0037] In addition, the controller 30 may select and control a transmittance mode corresponding to the input information IN. The controller 30 controls the voltage applied to the variable transparency glass 10 in the voltage controller 20 based on the transparency information selected by the user. The controller 30 may apply a voltage having one level selected from a plurality of levels for implementing the transmittance of the variable transparency glass 10 in multiple stages and varyingly.

[0038] In addition, the controller 30 can automatically control the transmittance mode based on the driving environment of the vehicle (e.g., weather, amount of sunlight, brightness changes, tunnels, glare, autonomous mode). Here, the controller 30 can work with a global positioning system (GPS) and a rain sensor to automatically control a transmittance mode optimized in a dark driving environment such as a tunnel and rain. In addition, the transparency of the sunroof glass to be shielded is controlled by detecting the outside temperature and visible light through sensors.

[0039] For example, the controller 30 may set a mode for transmitting natural light in a bright mode (transmittance of 70% or more). For example, when the surrounding environment is dark due to low brightness in a tunnel or rain, the controller 30 may automatically set to the bright mode.

[0040] In addition, the controller 30 can set the bright mode when the vehicle moves backward. That is, when the vehicle moves backward, the rear glass and side mirrors (inner side rearview mirror (ISRVM), outer side rearview mirror (OSRVM)) can be automatically switched to the bright mode, thereby ensuring safety and improving the visibility of the vehicle. According to another embodiment, during the automatic driving of the vehicle, the controller 30 can be set to the bright mode by the driver's demand or manual operation.

[0041] The controller 30 can set a mode to variably shield light in a variable tint mode (transmittance of 69% to 25%). That is, the controller 30 can set a variable tint mode to shield direct sunlight when the vehicle is parked or stopped. In addition, the transmittance of each glass is controlled based on the viewing mode of the display device of the vehicle (in response to the gradual non-transparent mode of the brightness and backlight) to improve the visibility of the content.

[0042] In addition, the controller 30 can set a mode that completely shields the light of the private suite area in the private mode (transmittance is 25% or less). That is, when the driver is resting or sleeping during the automatic driving of the vehicle, the controller 30 switches the mode to the private mode, thereby providing a comfortable transmittance (transmittance of 30% or less).

[0043] Here, the driver's sleep state can be detected by checking the driver's heart rate, by tracking the pupils using a camera, or by the driver's needs. In addition, the transmittance of the rear window can be controlled when the occupant in the back seat requests to switch to privacy mode.

[0044] According to an embodiment, when the outside temperature changes or the weather changes after the vehicle is parked, the transmittance can be remotely switched. When the outside temperature rises after the vehicle is parked, the user can use a smartphone application to switch the setting mode of the controller 30 to a non-transparent mode to shield ultraviolet rays, visible light, etc.

[0045] The memory 40 may include a lookup table (LUT) derived through preliminary experiments and evaluations to be established, and may store transmittance control information corresponding to each mode. The lookup table is a data table in which a voltage value supplied to the variable transparency glass 10 is set in response to the transparency or gray level of the variable transparency glass 10. In an embodiment of the present disclosure, the controller 30 controls the voltage of the voltage controller 20 based on the data stored in the lookup table of the memory 40.

[0046] When a user's selection is input under the voltage control of the controller 30 , the memory 40 may provide data of the lookup table to maximize the response speed of the transmittance adjustment in response to the user's selection.

[0047] Figure 3 is a detailed structural diagram of a variable transparency glass according to an embodiment of the present disclosure.

[0048] refer to Figure 3 , a variable transparency glass 10 according to an embodiment of the present disclosure includes a first film 11 , a second film 12 , and a liquid crystal (LC) capsule 13 .

[0049] The first film 11 and the second film 12 may be formed of a plate-shaped transparent material and may be disposed on the upper and lower sides of the variable transparency glass 10, respectively. The first film 11 and the second film 12 may control the refractive index corresponding to the electric field reaction. Here, the first film 11 and the second film 12 may be integrally embedded with a transparent electrode that is aligned in a vertical, horizontal or diagonal direction relative to the optical axis on the inner surface of each of the first film 11 and the second film 12 and rubbed.

[0050] In addition, a liquid crystal capsule 13 capable of controlling a phase is installed between the first film 11 and the second film 12. In response to the phase of the liquid crystal capsule 13, the transmittance can be controlled by the power provided by the voltage controller 20. The liquid crystal capsule 13 controls the phase of the first film 11 and the second film 12. The liquid crystal capsule 13 has a refractive index that can maintain the same or similar level with respect to the vertical direction of the circularly polarized light source.

[0051] Here, the liquid crystal capsule 13 is a capsule-type liquid crystal bundle of a polymer dispersed liquid crystal (PDLC) structure, and can be changed to a transparent or opaque state according to whether an electric field is applied.

[0052] For example, the liquid crystal capsule 13 may have the following physical properties: Min@100 μm, ε≤9.5, ε⊥≤3.3, anisotropy ne=1.6, and no=1.2. In an embodiment of the present disclosure, the physical properties of the liquid crystal capsule 13 as representative values ​​of a polymer satisfying surface resistance, conductivity, and refractive index may be calculated based on experimental data. However, the physical properties of the liquid crystal capsule 13 are not limited thereto.

[0053] The liquid crystal capsule 13 may have an anisotropic dielectric constant and may have an excellent contrast ratio. The liquid crystal capsule 13 may be arranged vertically, horizontally, or diagonally to the substrate surface by vertical and horizontal arrangement. As described above, the liquid crystal capsule 13 does not greatly affect the arrangement of the liquid crystal, and may control the transmittance with low turbidity (low refractive index) before and after voltage application, and may have excellent viewing angle characteristics.

[0054] In addition, the variable transparency glass 10 and the voltage controller 20 are connected by a power cable 50. The power cable 50 may be formed of a flexible flat cable (FFC) structure. The power cable 50 is connected to the variable transparency glass 10 as an integral type or as a fastening type of a lead type.

[0055] Figure 4 and Figure 5 yes Figure 3 Cross-sectional view of variable transparency glass.

[0056] refer to Figure 4 The variable transparency glass 10 includes a liquid crystal capsule 13 disposed between a first film 11 and a second film 12 .

[0057] According to one embodiment, the first film 11 and the second film 12 may be made of various polyesters (eg, polyethylene terephthalate (PET), 1PLY, 2PLY), dyed, slice-dyed, carbon, metal, ceramic, sputtered, nano-carbon ceramic, and the like.

[0058] Here, the dye film is a color conversion film that utilizes the relaxation and contraction of the film. In addition, the sheet dye film is a film formed by the color film material itself. The carbon film is a film in which carbon is added to the film material to improve durability. The metal film is a film in which a metal is deposited on the surface of the film to be coated.

[0059] Ceramic film is a film in which non-metallic and inorganic materials are processed and molded at high temperature. Sputtered film is a film in which metal components are coated in a thin layer of atomic structure under vacuum. Nano-carbon ceramic film is a film in which carbon film and ceramic film are combined.

[0060] In addition, a first transparent electrode 14 is included on the inner surface of the first film 11, and a second transparent electrode 15 is included on the inner surface of the second film 12. Here, the first transparent electrode 14 and the second transparent electrode 15 may be a light-transmitting inorganic substrate or an organic substrate, or an inorganic substrate or an organic substrate may be stacked in a uniform manner or in a heterogeneous manner.

[0061] The transparent electrodes 14 and 15 have sufficient carriers, which are media for transporting charges, and have low resistance to allow the carriers to move easily, thereby increasing the current rate. The transparent electrodes 14 and 15 are transparent materials that allow light to pass through. The transparent electrodes 14 and 15 can be defined based on the thickness, resistance and conductivity of each electrode 14 and 15, and the correlation of transmittance.

[0062] Since the transparent electrodes 14 and 15 are very thin films, the resistance changes sensitively even if the thickness changes slightly. The transparent electrodes 14 and 15 may have a sheet resistance, which is the resistance of the material surface, set to be lower than the specific resistance (e.g., 1000Ω / square) regardless of the thickness.

[0063] The conductivity and transmittance can be determined according to the band gap width of the transparent electrodes 14 and 15. That is, when the band gap width increases, the conductivity decreases, but the transparent electrodes 14 and 15 become transparent. When the band gap width decreases, the conductivity increases, but the transparent electrodes 14 and 15 become opaque.

[0064] Therefore, when the thickness increases, the resistance decreases, and the conductivity increases, but the transmittance decreases. Conversely, when the thickness decreases, the resistance increases, and the conductivity decreases to become transparent.

[0065] For example, the transparent electrodes 14 and 15 may be formed of a transparent conductive material of indium tin oxide (ITO), indium zinc oxide (IZO), graphene, poly(ethylene dioxythiophene), polystyrene sulfonate (PEDOT:PSS), silver nanowires, and carbon nanotubes (CNTs).

[0066] Here, indium tin oxide is formed by combining indium oxide (In2O3) and tin oxide (SnO2) to have excellent conductivity, high transmittance, provide electrical signals and transmit light. Graphene is a planar layer structure arranged in a carbon honeycomb hexagonal network. Graphene has high electrical conductivity, fast electron transfer, high strength and thermal conductivity, and can be applied to flexible devices.

[0067] Polystyrene sulfonate as a conductive polymer polymerizes ethylenedioxythiophene (EDOT) monomers to be synthesized. Polystyrene sulfonate has high conductivity, excellent flexibility and stability, and undergoes a simple coating process.

[0068] Silver nanowires are nano-microscopic wire bundles with silver cross-sections. Silver nanowires formed by growing nanosilver (Ag) in a linear shape on a substrate have excellent transparency and conductivity. Carbon nanotubes are bundle-shaped materials in which carbon is connected like a honeycomb, have a hexagonal honeycomb pattern, and have a size of 1 nanometer.

[0069] In addition, the liquid crystal capsule 13 includes a variable transmission layer 16, a liquid crystal droplet 17 and a liquid crystal molecule 18. The variable transmission layer 16 as a polymer optical device can be used as a polymer optical refractive material. The variable transmission layer 16 can be made of a transmissive liquid crystal polymer structure. The liquid crystal capsule 13 can be arranged to fill the space between the first transparent electrode 14 and the second transparent electrode 15.

[0070] The liquid crystal capsule 13 having the above structure has a light transmittance that varies depending on the electric field formed between the first transparent electrode 14 and the second transparent electrode 15. Therefore, the liquid crystal capsule 13 forms an opaque glass because the light transmittance becomes low when power is applied. The liquid crystal capsule 13 is characterized in that the light transmittance decreases as the voltage to be applied increases.

[0071] refer to Figure 5 When no voltage is applied between the first transparent electrode 14 and the second transparent electrode 15, the variable transmission layer 16 becomes a shadow state, thereby shielding light. The liquid crystal capsule 13 is a material having a light-transmitting property. Therefore, when a voltage is applied between the first transparent electrode 14 and the second transparent electrode 15, an electric field is formed in the liquid crystal capsule 13.

[0072] Therefore, the variable transmission layer 16 has polarization characteristics to change the phase of light incident from the outside to pass therethrough.

[0073] For example, the variable transmission layer 16 can convert incident light based on the voltage applied to both ends of the first transparent electrode 14 and the second transparent electrode 15. When the polymer has a phase in a vertical state, light incident from the outside is converted by 0°. Then, when the polymer has an inclined phase (an intermediate state between the vertical and horizontal states), light incident from the outside is converted by about 45°. In addition, when the polymer has a phase in a horizontal state, light incident from the outside is converted by about 90°.

[0074] Therefore, depending on the electric field applied to the variable transmission layer 16, the variable transparency glass 10 is configured to have various light transmittances based on the applied voltage, and can control transparency and transmittance.

[0075] Figure 6 An embodiment is shown in which the liquid crystal droplets 17 included in the above-mentioned variable transmission layer 16 are configured as a polymer three-dimensional spherical structure.

[0076] Fig. 7A and Figure 7B It is used to illustrate Figure 3 A view of a pattern structure of the variable transparency glass 10.

[0077] refer to Fig. 7A and Figure 7BIn the variable transparency glass 10 according to the embodiment of the present disclosure, the alignment pattern structures of the first transparent electrode 14 and the second transparent electrode 15 may be different from each other. For example, the sub-electrodes of the first transparent electrode 14 may have the following structure: Figure 7B The sub-electrodes of the second transparent electrode 15 may have the following Fig. 7A The pattern structure shown is arranged horizontally.

[0078] Figure 8 It is used to illustrate Figure 3 View of the partial transmittance of the variable transparency glass.

[0079] refer to Figure 8 , the variable transparency glass 10 according to the embodiment of the present disclosure performs partial control on the internal phase when the films 11 and 12 overlap each other, thereby controlling the transmittance of the selected portion.

[0080] The variable transparency glass 10 according to the embodiment of the present disclosure can separate the regions of the films 11 and 12 based on the mode set in the controller 30 to control the regions of different transmittances. That is, the portion overlapped by the films 11 and 12 in the same glass is divided into upper / lower and left / right regions. In addition, the variable transparency glass 10 can separately provide the voltage applied from the voltage controller 20 to each separated region, thereby partially controlling the transmittance of the region.

[0081] For example, in region (1), a voltage of 12 V is provided in the vertical direction, a voltage of 6 V is provided in the horizontal direction, and thus the potential difference is set to 6 V. In region (2), a voltage of 6 V is provided in the vertical direction, a voltage of 6 V is provided in the horizontal direction, and thus the potential difference is set to 0 V.

[0082] In region (3), a voltage of 12 V is provided in the vertical direction, a voltage of 3 V is provided in the horizontal direction, and thus the potential difference is set to 9 V. In region (4), a voltage of 6 V is provided in the vertical direction, a voltage of 3 V is provided in the horizontal direction, and thus the potential difference is set to 3 V. Therefore, in the embodiment of the present disclosure, the transmittance can be partially controlled in response to the potential difference of the separate regions (1) to (4), respectively.

[0083] Fig. 9 as well as Fig.10 is a view for illustrating a transparent mode and a non-transparent mode depending on a transmittance switcher.

[0084] The embodiments of the present disclosure may control the phases of the transparent electrodes 14 and 15 to switch the transmittance and the refractive index, thereby controlling the linear change of the transparent mode and the non-transparent mode.

[0085] refer to Fig. 9, in the "transparent mode", the transparent electrodes 14 and 15, each having an isotropic refractive index, are aligned and rubbed to be molded. Then, the voltage of the liquid crystal capsule 13 is controlled to control the refractive index and transmittance having an isotropic refractive index. For example, the refractive index n1 of the films 11 and 12 including the transparent electrodes 14 and 15 can be controlled to be 1.2, and the refractive index n2 of the liquid crystal capsule 13 can be controlled to be 1.2.

[0086] That is, the refractive indexes of the liquid crystal capsule 13, the transparent electrode 14 having a vertical pattern, and the transparent electrode 15 having a horizontal pattern are all controlled to be isotropic refractive indexes. Then, non-polarized light can be transmitted from the light source to realize the transparent mode.

[0087] refer to Fig.10 In the "non-transparent mode", the voltage is controlled to shift the phase of the liquid crystal capsule 13 to π / 2 relative to the transparent mode while maintaining the isotropic refractive index. That is, circularly polarized light is shielded, the refractive index of the liquid crystal capsule 13 is changed, and thus the transmittance is controlled. For example, the refractive index n1 of the films 11 and 12 including the transparent electrodes 14 and 15 can be maintained at 1.2, and the refractive index n2 of the liquid crystal capsule 13 can be phase-shifted to 1.6 or more.

[0088] That is, when the transparent electrode 14 with a vertical pattern and the transparent electrode 15 with a horizontal pattern overlap, circularly polarized light is transmitted. Then, when the refractive index is switched by the liquid crystal capsule 13, the circularly polarized light is scattered, and the linearly polarized light is absorbed or quenched to realize a non-transparent mode in which circularly polarized light is not transmitted.

[0089] Fig.11 It is used to illustrate Figure 3 A plot of the linear control level of transmittance of the variable transparency glass.

[0090] refer to Fig.11 In the embodiment of the present disclosure, when the voltage increases, the transmittance can be linearly controlled. Conversely, an inverse control can be performed so that the transmittance decreases as the voltage increases.

[0091] In the embodiment of the present disclosure, the voltage applied by the voltage controller 20 is linearly controlled to perform linear control of the transparent mode or the non-transparent mode. In addition, the refractive index is matched with each stacked layer for haze control, and thus the transmittance can be switched without haze and scattering.

[0092] Fig.12 yes Figure 2 A block diagram of the voltage controller 20 is shown in FIG.

[0093] refer to Fig.12 The voltage controller 20 includes a control signal generator 21 and an output switching device 22 .

[0094] Here, the control signal generator 21 controls the linear voltage level value to automatically switch the transmittance in response to the vehicle environment. That is, the control signal generator 21 controls the voltage level value to automatically select the transmittance level in response to the control signal CON applied from the controller 30.

[0095] For example, the control signal generator 21 may control the voltage level value to have a transmittance of 70% or more for transmitting natural light in the bright mode. The control signal generator 21 may control the voltage level value to change the transmittance to a range of 69% to 25% for variably shielding light in the variable tint mode. In addition, the control signal generator 21 may control the voltage level value to have a transmittance of 25% or less for completely shielding light relative to the privacy optimal area in the private mode.

[0096] The control signal generator 21 generates a control signal TG for providing a linear output voltage VOUT in response to the control signal CON. 1 TG 2 , BG 1 and BG 2 The control signal generator 21 can variably control the control signal TG by pulse width modulation. 1 TG 2 , BG 1 and BG 2 .

[0097] In addition, the output switching device 22 includes a plurality of switching elements T 1 To T 4 , resistor R 1 and a current tilting device 25 .

[0098] Here, multiple switching elements T 1 To T 4 A switching converter may include a metal oxide semiconductor field effect transistor (MOSFET) structure,

[0099] That is, in the switching element T 1 and T 2 Connected in series between the input voltage VIN application terminal and the resistor R 1 Control signal TG 2 The gate terminal is applied to the switching element T 1 .

[0100] In addition, the control signal BG 2 The gate terminal is applied to the switching element T 2 In addition, the switching element T 3 and T 4 The output voltage VOUT is connected in series with the resistor R 1Control signal TG 1 The gate terminal is applied to the switching element T 3 . Control signal BG 1 The gate terminal is applied to the switching element T 4 .

[0101] Resistor R 1 Connect the switch element T 2 and T 4 The current tilting device 25 is connected between the switching element T 1 and T 2 The contact and switch element T 3 and T 4 Here, the current tilting device 25 may include an inductor.

[0102] In response to the plurality of switch elements T 1 To T 4 By means of the selective switching operation, the output switching device 22 having the above configuration reduces or increases the input voltage VIN to linearly control the output voltage VOUT.

[0103] For example, when the switching element T 1 The switch element T is turned on and 2 When disconnected, the control signal TG 1 and BG 1 To switch the switching element T 3 and T 4 , to increase the output voltage VOUT. On the other hand, when the switching element T 4 The switch element T is turned on and 3 When disconnected, the control signal TG 2 and BG 2 To switch the switching element T 1 and T 2 , to reduce the output voltage VOUT.

[0104] In addition, when the output switching device 22 is turned off, the plurality of switch elements T 1 To T 4 is turned off, so the input voltage VIN and the output voltage VOUT can be cut off from each other.

[0105] In addition, the output switching device 22 switches the phase of the voltage to prevent permanent adhesion of the liquid crystal capsule 13. For example, the output voltage VOUT is switched from 12V to -12V or from 6V to -6V.

[0106] Therefore, when the vehicle is started or shut down, the phase of the liquid crystal capsule 13 is reversely driven. For example, the phase of the liquid crystal capsule 13 may be reversed from π to 2π or from π / 2 to 3π / 2.

[0107] Fig.13 It is shown Fig.12 20 is a waveform diagram of a control method of the voltage controller 20.

[0108] refer to Fig.13 , the voltage controller 20 can provide a linear control voltage. In the embodiment of the present disclosure, it will be described as an example that the output switching device 22 has a buck converter structure.

[0109] The voltage controller 20 generates the power supply current IS based on the pulse width of the control signal applied from the control signal generator 21. 1 and diode current ID 1 In addition, the inductor current IL1 maintains a constant current value within a specific range corresponding to the power supply current IS1 and the diode current ID1. The output voltage VS1 can be set to Ton (low pulse width) / T (period).

[0110] Fig.14 is a flow chart illustrating a method of controlling variable transparency glass according to an embodiment of the present disclosure.

[0111] refer to Fig.14 In S1, opening or closing of the first film 11 and the second film 12 of the variable transparency glass 10 is selected. Thereafter, the refractive index of each of the selected first film 11 and the second film 12 is controlled in S2.

[0112] Next, the voltage controller 20 is enabled in S3, and the output switching device 22 performs an increase or decrease in voltage in S4. When shutdown occurs, the output voltage VOUT is cut off in S5.

[0113] Thereafter, corresponding to the control of the controller 30 in S6, the voltage controller 20 controls the output voltage VOUT supplied to the variable transparency glass 10. In S7, the controller 30 controls the voltage level supplied to the variable transparency glass 10 with reference to the data stored in the memory 40. Then, in S8, the voltage controller 20 outputs a linear voltage to the variable transparency glass 10 to control the transparency of the variable transparency glass 10 in S9.

[0114] As described above, the embodiments of the present disclosure can apply variable transparency glass to window devices of autonomous vehicles. For example, vehicle glass can be applied to windshields, sunroofs, door windows, rear glass, interior rearview mirrors, exterior rearview mirrors, etc.

[0115] In this case, the embodiments of the present disclosure can be implemented in vehicle glass without changing the configuration of glass hardware pre-configured in existing vehicles. In addition, marketability can be improved while minimizing cost increases without reducing performance. In addition, technical and commercial competitiveness can be improved by adding a polarization function.

[0116] That is, the transmittance of the vehicle glass can be automatically switched using a simple switching operation according to the environment (e.g., weather, sunlight) to automatically shield the sunlight passing through the window. A privacy zone can be built into an autonomous vehicle to protect passengers from the external environment and reflect the needs of consumers.

[0117] In addition, the embodiments of the present disclosure can replace electrically driven curtains and shades for vehicles to reduce costs. In addition, the use of air conditioners can be reduced to reduce energy consumption. The embodiments of the present disclosure can be applied to private areas, energy-saving areas, or aesthetic and invisible areas.

[0118] In addition, the embodiments of the present disclosure can be applied to devices that replace blinds and curtains (automotive smart window fields, office buildings, greenhouses, commercial and residential buildings, greenhouses, security, private buildings, briefing rooms, conference rooms, video promotion rooms, situation centers, etc.). Therefore, glass with variable transmittance can be realized and used as a device to replace blinds and curtains.

[0119] In addition, the embodiments of the present disclosure can be used for environmentally friendly energy reduction projects. For example, it can be applied to eco-friendly buildings (living spaces that automatically shield sunlight on windows) to save energy for lighting, heating and cooling. When polysilicon is applied to the interior of glass, green energy technology can be implemented as solar power generation and power conversion.

[0120] Embodiments of the present disclosure allow for variably controlling the transparency of glass in response to user and environmental demands.

[0121] Furthermore, embodiments of the present disclosure provide a glass in which the transparency of certain portions of the glass is selectively adjusted to precisely control the glass.

[0122] In addition, the embodiments of the present disclosure are for illustrative purposes, and those skilled in the art will understand that various changes, modifications, substitutions and additions may be made thereto within the spirit and scope of protection of the appended claims, and these changes and modifications should be deemed to fall within the scope of protection of the appended claims.

[0123] Although the present disclosure has been described above with reference to exemplary embodiments and the accompanying drawings, the present disclosure is not limited thereto but may be variously modified and changed by those skilled in the art without departing from the spirit and scope of the present disclosure as claimed in the appended claims.

Claims

1. A variable transparency glass, comprising: a first film having a first transparent electrode on an inner surface of the first film; a second film having a second transparent electrode on an inner surface of the second film; as well as a liquid crystal capsule disposed between the first film and the second film, and configured to control transmittance of incident light in response to a voltage applied to each of the first transparent electrode and the second transparent electrode, wherein when the first film and the second film overlap, the liquid crystal capsule partially controls transmittance corresponding to an alignment pattern of each of the first transparent electrode and the second transparent electrode, Wherein, when the refractive index of the first transparent electrode and the refractive index of the second transparent electrode are respectively the same as the refractive index of the liquid crystal capsule, the glass is configured to be controlled in a transparent mode, When the refractive index of the first transparent electrode and the refractive index of the second transparent electrode are respectively different from the refractive index of the liquid crystal capsule, the glass is controlled in a non-transparent mode. The first transparent electrode, the second transparent electrode, and the liquid crystal capsule all have isotropic refractive index, and When the vehicle is started or shut down, the phase of the liquid crystal capsule is driven in reverse according to the switching of the voltage phase.

2. The variable transparency glass according to claim 1, wherein: The transmittance changes in response to a level of the voltage.

3. The variable transparency glass according to claim 1, wherein: The voltage has a linear voltage level.

4. The variable transparency glass according to claim 1, wherein: The first transparent electrode and the second transparent electrode are aligned in a vertical direction, a horizontal direction, or a diagonal direction with respect to an optical axis.

5. The variable transparency glass according to claim 1, wherein: The liquid crystal capsule has a polymer dispersed liquid crystal structure.

6. The variable transparency glass according to claim 1, wherein: The liquid crystal capsule is disposed between the first transparent electrode and the second transparent electrode, and the liquid crystal capsule includes a variable transmission layer of a liquid crystal polymer structure.

7. An apparatus for controlling the transmittance of variable transparency glass, comprising: a variable transparency glass configured to variably control transmittance according to a voltage; a voltage controller configured to supply the voltage to the variable transparency glass; as well as a controller configured to select a transmittance mode in response to input information and control a level of the voltage based on the selected transmittance mode, Wherein, the variable transparency glass comprises: a first film having a first transparent electrode on an inner surface of the first film; a second film having a second transparent electrode on an inner surface of the second film; and a liquid crystal capsule disposed between the first film and the second film and configured to variably control transmittance of incident light in response to a voltage applied to each of the first transparent electrode and the second transparent electrode, Wherein, when the refractive index of the first transparent electrode and the refractive index of the second transparent electrode are respectively the same as the refractive index of the liquid crystal capsule, the glass is configured to be controlled in a transparent mode, When the refractive index of the first transparent electrode and the refractive index of the second transparent electrode are respectively different from the refractive index of the liquid crystal capsule, the glass is controlled in a non-transparent mode. The first transparent electrode, the second transparent electrode and the liquid crystal capsule all have isotropic refractive index, and When the vehicle is started or shut down, the phase of the liquid crystal capsule is driven in reverse according to the switching of the voltage phase.

8. The device according to claim 7, wherein: The voltage controller comprises: a control signal generator configured to generate a control signal that changes a pulse width according to control of the controller; and An output switching device is configured to increase or decrease the voltage based on the control signal.

9. The device according to claim 8, wherein: The output switching device is configured to linearly control the voltage based on the control signal.

10. The device according to claim 8, wherein: The output switching device comprises: a plurality of switch elements configured to be selectively switched in response to the control signal; and The current ramping device is configured to ramp the current flowing at the plurality of switch elements and limit the foldback output current.

11. The device according to claim 10, wherein: The output switching device is configured such that the voltage is not provided during an off operation when the plurality of switching elements are turned off.

12. The device according to claim 7, wherein: The controller is configured to control the transmittance differently based on a level value of the voltage when the transmittance mode is changed to a bright mode, a variable tint mode, or a privacy mode.

13. The apparatus according to claim 7, wherein: The controller is configured to change the transmittance mode in response to environmental information, user input information, or manual operation. 14 . The apparatus of claim 7 , further comprising a memory configured to store transmittance control information in response to the transmittance mode.

15. The device according to claim 14, wherein: The memory includes a lookup table in which a value of the voltage is set in response to the transmittance pattern.

16. The apparatus according to claim 7, wherein: The variable transparency glass is configured to partially control transmittance corresponding to an alignment pattern of each of the first transparent electrode and the second transparent electrode when the first film overlaps the second film.

17. The device according to claim 16, wherein: The variable transparency glass is divided into a plurality of regions within an overlapping region of the first film and the second film, and is configured to control the transmittance differently according to a potential difference of each of the regions when a separate voltage is applied to each of the regions.

18. The apparatus according to claim 7, wherein: The first transparent electrode and the second transparent electrode are aligned in a vertical direction, a horizontal direction, or a diagonal direction with respect to an optical axis.

19. The apparatus according to claim 7, wherein: The liquid crystal capsule is disposed between the first transparent electrode and the second transparent electrode, and includes a variable transmission layer of a liquid crystal polymer structure.

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