Method for switching the state of switchable glass

Abstract

The present invention provides a method for switching the state of a switchable glass to eliminate the time delay when the conventional switchable glass switches from a cloudy state to a transparent state. The method includes a transparent stage, an operation stage, and a state switching stage. In the transparent stage, no voltage is applied to the switchable glass, and the switchable glass is in a transparent state. In the operation stage, an alternating current is applied to the switchable glass, and the amplitude of the alternating current is maintained at a first voltage, and the switchable glass is in a scattered state. In the state switching stage, after the operation stage, the amplitude of the alternating current is raised to a second voltage, and the second voltage is higher than the first voltage, and the switchable glass is maintained in a scattered state. After maintaining the state switching stage over a duration, the application of the alternating current is stopped to return to the transparent state and restore the switchable glass to the transparent state.

Description

Technical Field

[0001] The present invention relates to the technology of optoelectronic components, and more particularly, to a method for switching a switchable glass to a privacy protection state and quickly returning it to a transparent state.

Background Art

[0002] Conventional glass provides shielding or protection of the space inside the glass while enabling illumination and visual recognition of objects on different sides of the glass. The surface of the glass may be clouded or a matte film may be attached to the surface of the glass, whereby light passes through and scatters through the glass to form a blurred image on the other side of the glass. In this way, the glass realizes privacy protection while maintaining the lighting function. In addition, conventional switchable glass can be switched between a transparent state and a cloudy state through an active control method such as energization.

[0003] In conventional switchable glass, an electric field is changed to disrupt liquid crystal molecules, which multiply-scatter light incident on the glass. However, after the voltage source stops power supply, residual charge ions can form a temporary internal electric field. As a result, the liquid crystal molecules cannot quickly return to the transparent state before energization. Therefore, conventional switchable glass has problems such as delay in mode switching, poor controllability, and reduced visual effects.

[0004] From the above, it is necessary to improve conventional switchable glass.

Summary of the Invention

Problems to be Solved by the Invention

[0005] In order to solve the above problems, an object of the present invention is to provide a method for switching the state of switchable glass, which enables quick switching between a privacy protection state and a transparent state.

[0006] Another object of the present invention is to provide a method for switching the state of switchable glass that can improve the cloudy visual effect of the switchable glass.

[0007] Still another object of the present invention is to provide a method for switching the state of switchable glass that can reduce the power consumption of state switching.

[0008] As used herein, the terms "a", "an", or "one" representing the number of elements and members of the present invention are used for convenience and provide a general meaning of the scope of the present invention and should be construed as including one or at least one. Further, unless otherwise expressly stated, the concept of a single component also includes the case of a plurality of components.

Means for Solving the Problems

[0009] The method for switching the state of the switchable glass of the present invention includes a transparent stage, an operation stage, and a state switching stage. In the transparent stage, no voltage is applied to the switchable glass, and the switchable glass is in a transparent state. In the operation stage, an alternating current is applied to the switchable glass, and the amplitude of the alternating current is maintained at a first voltage, and the switchable glass is in a scattered state. In the state switching stage, the amplitude of the alternating current is increased to a second voltage after the operation stage, and the second voltage is higher than the first voltage, and the switchable glass maintains the scattered state. The application of the alternating current is stopped after being maintained for a duration of the state switching stage and returns to the transparent stage, and the switchable glass returns to the transparent state.

[0010] In this way, in the method for switching the state of the switchable glass according to the present invention, by applying an alternating current of a first voltage to the switchable glass, the power consumption for maintaining the scattering state can be reduced. Further, by applying an alternating current of a second voltage to the switchable glass and stopping the power supply after a duration, the response time required for the switchable glass to return from the scattering state to the transparent state can be shortened. Therefore, according to this method, the delay of mode switching can be reduced, the visual effect of the switchable glass can be improved, and the power consumption can be reduced.

[0011] For example, the first voltage is the minimum voltage value at which the alternating current causes the haze value of the switchable glass to reach 80% or more. Therefore, the switchable glass can maintain privacy protection with minimum energy consumption, thereby saving power.

[0012] For example, the second voltage is the voltage value at which the shortest response time is required for the switchable glass to return to the transparent state when the application of the alternating current to the switchable glass is stopped. Therefore, the switching delay from the scattering state to the transparent state can be significantly reduced for the switchable glass, thereby improving the controllability of state switching.

[0013] For example, the above-mentioned duration is the shortest time required to apply the alternating current of the second voltage when the response time required for the switchable glass to return to the transparent state is less than 0.5 seconds. Therefore, the application time of the alternating current of high voltage can be shortened, thereby reducing the power consumption and realizing the high-speed state switching of the switchable glass.

[0014] For example, the switchable glass includes two substrates and a liquid crystal material located between the two substrates. The two substrates are transparent and conductive. The liquid crystal material includes a negative liquid crystal and salt ions. Therefore, the electric field can be switched to act on the liquid crystal material, whereby the liquid crystal material is disturbed by the change of the electric field and exhibits a plurality of scattering states, thereby realizing the switching of the switchable mode through electric control.

Brief Description of the Drawings

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Figure 1

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Figure 2

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Figure 3

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Figure 4

[0019]

Figure 5

Modes for Carrying Out the Invention

[0020] Detailed Description of the Invention

[0021] The present invention will be more fully understood from the following detailed description and the accompanying drawings (which are for illustrative purposes only and thus do not limit the present invention). Further, the same reference numerals in different accompanying drawings represent the same components, and the description thereof is omitted in this specification.

[0022] Figure 1 is an exemplary embodiment of a method for switching the state of switchable glass according to the present invention. This method includes a transparent stage S1, an operating stage S2, and a state switching stage S3. The state switching stage S3 includes a transition from the operating stage S2 to the transparent stage S1, thereby switching the switchable glass from a privacy protection state to a bi-directional transmission state.

[0023] Referring to FIG. 2, the switchable glass can be formed by injecting a liquid crystal material 1 between two transparent and conductive substrates 2. The two substrates 2 are electrically connected to a voltage source to form an electric field acting on the liquid crystal material 1, thereby controlling the alignment direction of the liquid crystal. In this way, incident light can directly pass through the liquid crystal material 1 or be scattered, thereby realizing switching of the switchable glass between a transparent and a cloudy state. In this embodiment, the liquid crystal material 1 includes a negative liquid crystal and salt ions, and the two substrates 2 act on the vertically aligned liquid crystal material 1. As shown in FIG. 2, when the two substrates 2 are not charged, the liquid crystal molecules in the liquid crystal material 1 are regularly arranged perpendicular to the two substrates 2, whereby light directly passes through the switchable glass, which indicates a transparent state. When an alternating voltage is applied between the two substrates 2, the liquid crystal molecules are disturbed by the change in the electric field and thus arranged randomly, whereby light diffuses after its path changes several times within the liquid crystal material 1, which indicates a scattered state.

[0024] Referring to FIG. 1, during the transparent stage S1, no voltage is applied to the switchable glass, whereby the switchable glass is in a transparent state. In this case, a clear image passing through the switchable glass can be viewed on its inner or outer side.

[0025] When switching from the transparent state S1 to the operating state S2, an alternating current is applied to the switchable glass. The amplitude of the alternating current is the first voltage V1, and the frequency of the alternating current may be the normal operating frequency of a general power transmission network, such as 50 Hz or 60 Hz. In this regard, the present invention is not limited. When the alternating current is maintained at the first voltage, the switchable glass is in a scattered state. In this case, a cloudy image can be seen through the switchable glass.

[0026] When entering from the operation stage S2 to the state switching stage S3, the amplitude of the alternating current is raised to the second voltage V2. The second voltage V2 is greater than the first voltage V1. The frequency of the alternating current can be maintained unchanged. The state switching stage S3 includes maintaining the alternating current at the second voltage V2 over a duration T, thereby maintaining the switchable glass in a scattered state. After the duration T, the supply of the alternating current is stopped and it returns to the transparent stage S1, thereby immediately restoring the switchable glass to the transparent state.

[0027] Figure 3 shows the relationship between the haze value of the switchable glass and the voltage value applied to the switchable glass in this embodiment. When the alternating current applied to the switchable glass rises above 15 volts, the haze value can reach 80% - 94%. Since it is difficult for the human eye to distinguish the difference in the shielding effect brought about by a haze value of 80% or more, the minimum voltage value that can achieve a haze value of 80% or more is used when the switchable glass is used for long-term privacy protection in the operation stage S2, which can save power. Referring to FIGS. 1 and 3, in this embodiment, the voltage value that can achieve a haze value of 80% is in the range of 10V - 15V. Therefore, the first voltage V1 used in the operation stage S2 can be 15 volts.

[0028] FIG. 4 shows the relationship between the response time required for the switchable glass of the present embodiment to restore transparency after the application of the alternating current is stopped and the applied voltage value. When the amplitude of the alternating current is 14 volts, when the power supply to the switchable glass is stopped, the switchable glass requires a response time of 8.5 seconds to return from the scattered state to the transparent state. On the other hand, when an alternating current of more than 22 volts is used, the response time can be shortened to less than 1 second. Referring again to FIGS. 1 and 4, in the present embodiment, the second voltage V2 used in the state switching stage S3 is preferably 40 volts, and the required response time is 0.36 seconds.

[0029] Please refer to FIGS. 1, 3, and 4. From FIG. 4, it can be seen that when the alternating current is less than 12 volts, the response time for the switchable glass to restore transparency can be made less than 0.35 seconds. However, from FIG. 3, it can be seen that when the alternating current is less than 12 volts, the haze value of the switchable glass is less than 80%, and complete privacy protection cannot be achieved. Therefore, neither the first voltage V1 used in the operation stage S2 nor the second voltage V2 used in the state switching stage S3 can be less than 12 volts.

[0030] FIG. 5 shows the relationship between the duration for which the alternating current applied to the switchable glass of the present embodiment is maintained at 40 V and the response time required to restore transparency. Referring again to FIG. 1, in the present embodiment, an alternating current of 15 V is first applied to the switchable glass for 10 seconds, after which the alternating current is raised to 40 V and the supply of the alternating current is stopped after the duration T has elapsed. As shown in FIG. 5, when the duration T is 90 milliseconds, the response time required for the switchable glass to restore transparency can be shortened to 0.5 seconds. On the other hand, when the power supply is directly stopped at 15 V without raising the alternating current to 40 volts (i.e., when the duration T is 0 seconds), a response time of nearly 11 seconds is required to restore the transparency of the switchable glass. Therefore, when the duration T is more than 90 milliseconds, the delay in switching from the scattered state to the transparent state of the switchable glass can be significantly reduced. Also, from FIG. 5, it can be seen that after the duration T increases beyond 90 milliseconds, the response time does not decrease significantly. Therefore, the duration T is preferably 90 milliseconds.

[0031] According to the above, in the state switching method of the switchable glass of the present invention, by applying an alternating current of a first voltage to the switchable glass, the power consumption for maintaining the scattered state can be reduced. Also, by applying an alternating current of a second voltage to the switchable glass and stopping the power supply after the duration has elapsed, the response time required for the switchable glass to return from the scattered state to the transparent state can be shortened. Therefore, according to this method, the delay in mode switching can be reduced, the visual effect of the switchable glass can be improved, and the power consumption can be reduced.

[0032] Although the present invention has been described in detail with reference to the preferred embodiments herein, those skilled in the art will understand that various modifications can be made without departing from the spirit and scope of the invention as set forth in the appended claims.

Explanation of Reference Numerals

[0033] Reference number S1 Transparency stage S2 Operation stage S3 State switching stage 1 Liquid crystal material 2 Substrate V1 First voltage V2 Second voltage T Duration

Claims

1. A method for switching the state of switchable glass, comprising: A transparent stage where no voltage is applied to the switchable glass and the switchable glass is in a transparent state; An operating stage where an alternating current is applied to the switchable glass, the amplitude of the alternating current is maintained at a first voltage, and the switchable glass is in a scattered state; and A state switching stage where, after the operating stage, the amplitude of the alternating current is raised to a second voltage, the second voltage is greater than the first voltage, the switchable glass maintains the scattered state, and after the application of the alternating current is maintained for a duration of the state switching stage and then stopped, the switchable glass returns to the transparent state and the switchable glass reverts to the transparent state. A method for switching the state of switchable glass, including the above steps.

2. The method for switching the state of switchable glass according to Claim 1, wherein the first voltage is the minimum voltage value at which the alternating current causes the haze value of the switchable glass to reach 80% or more.

3. The method for switching the state of switchable glass according to Claim 1, wherein the second voltage is the voltage value at which the shortest response time is required for the switchable glass to return to the transparent state when the application of the alternating current to the switchable glass is stopped.

4. The method for switching the state of switchable glass according to Claim 1, wherein the duration is the shortest time when it is necessary to apply the alternating current of the second voltage when the response time required for the switchable glass to return to the transparent state is less than 0.5 seconds.

5. The method for switching the state of switchable glass according to any one of Claims 1 to 4, wherein the switchable glass includes two substrates and a liquid crystal material located between the two substrates, the two substrates are transparent and conductive, and the liquid crystal material includes a negative liquid crystal and salt ions.

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