Smart film for display

Abstract

The invention provides an optical device comprising a first transparent conductive electrode (1), a second transparent conductive electrode (2) and an active optical material (3) arranged between the first transparent conductive electrode (1) and the second transparent conductive electrode (2) in electrical contact with the first transparent conductive electrode (1) and the second transparent conductive electrode (2). The active optical material (3) is configured to change at least one optical property when a voltage is applied. The first transparent conductive electrode (1) and the second transparent conductive electrode (2) are divided into sub-regions (11-19, 21-23), each sub-region being electrically isolated from the other sub-regions within the sub-region. The optical device further comprises a control unit (6) configured to provide an electrical signal to each of the first zones (11-15) and to each of the second zones (21-23), where the control unit (6) is configured to provide at least a first scene and a second scene, where the first scene and the second scene are different from each other. All the second partitions receive the same electric signals in the first scene and at least two first partitions receive different electric signals, and all the first partitions receive the same electric signals in the second scene and at least two second partitions receive different electric signals.

Description

Technical Field

[0001] The present invention belongs to the field of smart films and smart glazes, and includes electro-modifiable elements embedded between two conductive substrates. Background Art

[0002] Smart film and glaze systems are typically used to create instant privacy and / or scenic images, and are applied to partitions and windows in exhibition halls, exhibitions, hotels, and the automotive industry. They are further used as barriers against ultraviolet and infrared rays to save energy and bring comfort to the application space.

[0003] As a specific example of switchable smart films and glazes, polymer dispersed liquid crystals (PDLCs) are studied herein. The device is capable of converting transparent partitions of a substrate into opaque partitions, and vice versa, by independently controlling each partition or converting these partitions to translucent according to the state of the liquid crystal.

[0004] The present invention uses this technology, but proposes a system that advantageously improves the use and final result of the device. Summary of the Invention

[0005] The present invention provides an alternative solution for PDLC screens by means of the device of claim 1. Preferred embodiments of the present invention are defined in the dependent claims.

[0006] Unless otherwise defined, all terms (including technical and scientific terms) used in the present invention shall be interpreted in accordance with the custom in the art. It should also be understood that terms in common usage shall also be interpreted in accordance with the custom in the art, rather than in an idealized or overly formal sense, unless explicitly defined in the present invention.

[0007] In this document, the terms "comprising" and its variants (e.g., "including", etc.) should not be construed in an exclusive sense, i.e., these terms should not be construed as excluding the possibility that the described and defined content may include other elements, steps, etc.

[0008] In a first aspect of the invention, the present invention provides an optical device, the optical device including a first transparent conductive electrode, a second transparent conductive electrode, and an active optical material, the active optical material being disposed between the first transparent conductive electrode and the second transparent conductive electrode and being in electrical contact with the first transparent conductive electrode and the second transparent conductive electrode,

[0009] wherein the active optical material is configured to change at least one optical property when a voltage is applied;

[0010] wherein the first transparent conductive electrode is divided into first partitions, each first partition being electrically isolated from the remaining first partitions in the first partition,

[0011] Wherein, the second transparent conductive electrode is divided into second partitions, and each second partition is electrically isolated from the remaining second partitions in the second partition.

[0012] Wherein, the optical device further includes a control unit configured to provide electrical signals to each first partition in the first partition and each second partition in the second partition. Wherein, the control unit is configured to provide at least a first scenario and a second scenario. In the first scenario, all the second partitions receive the same electrical signal and at least two first partitions receive different electrical signals. In the second scenario, all the first partitions receive the same electrical signal and at least two second partitions receive different electrical signals.

[0013] An active optical material is a material configured to change at least one optical property (e.g., transparency to a specific range of light wavelengths) when a voltage is applied across its two sides. There are various different types of active optical materials.

[0014] Due to this structure, the same optical device can operate in two different scenarios. In the first scenario, since all the second partitions are fed the same electrical signal, all the second partitions act as a single electrode. The first partitions will be fed different signals (it is not necessary for each first partition to have its own different signal, and the second partitions can be grouped), and the relationship between the signal of each specific first partition and the common signal of the second partitions will define the transparency level of each first partition.

[0015] The second scenario has the same principle, but the first partitions are replaced by the second partitions and vice versa.

[0016] Therefore, depending on the selected scenario, the same optical system is configured to provide two completely different patterns.

[0017] In some specific embodiments, the control unit includes a first element configured to receive a sinusoidal alternating current and convert it into a direct current signal, and includes a second element configured to convert the direct current signal into an alternating square wave, and includes a third element configured to generate a phase shift signal according to the square wave and feed the phase shift signal to the first partition and the second partition.

[0018] The control unit uses a common power supply to generate multiple phase-shifted square waves. These square waves are easy to compare. Since the optical properties of the active optical element depend on the voltage across its two sides, comparing two square waves is beneficial for defining the operation of each partition of the optical device.

[0019] In some specific embodiments, the thickness of the active optical material is 5 microns to 100 microns.

[0020] A smaller thickness is not sufficient for the present application.

[0021] In some specific embodiments, the first transparent conductive electrode and / or the second transparent conductive electrode comprises indium tin oxide, silver nanowires, carbon nanotubes, graphene, a transparent conductive polymer, or a nano metal.

[0022] These examples correspond to materials that provide a good compromise between transparency and conductivity.

[0023] In some specific embodiments, the first transparent conductive electrode is disposed on a first transparent substrate and / or the second transparent conductive electrode is disposed on a second transparent substrate.

[0024] The present invention can be applied to a variety of different types of substrates. In some specific embodiments, the first transparent substrate and / or the second transparent substrate comprises glass. In different specific embodiments, the first transparent substrate and / or the second transparent substrate comprises a plastic film made of polyethylene terephthalate.

[0025] In some specific embodiments, the first transparent substrate and / or the second transparent substrate comprises an infrared coating.

[0026] This is beneficial for blocking infrared radiation.

[0027] In some specific embodiments, the active optical material comprises polymer dispersed liquid crystal.

[0028] This material can operate over a wide range of voltage values and provides good transparent and opaque characteristics.

[0029] In some specific embodiments, the active optical material comprises black dichroic dye Polymer Dispersed Liquid Crystal.

[0030] This material further provides infrared protection.

[0031] In a further aspect of the invention, the present invention provides a method of manufacturing an optical device according to any one of the above claims, comprising the steps of:

[0032] Providing a first transparent conductive electrode, a second transparent conductive electrode, and an active optical material, wherein the active optical material is configured to change at least one optical property when a voltage is applied, and the active optical material comprises a first surface and a second surface, the second surface being opposite to the first surface;

[0033] Attaching the first transparent conductive electrode to the first surface of the optical material and attaching the second transparent conductive electrode to the second surface of the active optical material, thereby obtaining a prepared film;

[0034] Etch the first transparent conductive electrode into first partitions, each first partition being electrically isolated from the rest of the first partitions, wherein the etching process is accomplished by means of a picosecond ultraviolet laser device;

[0035] Etch the second transparent conductive electrode into second partitions, each second partition being electrically isolated from the rest of the second partitions, wherein the etching process is accomplished by means of a picosecond ultraviolet laser device;

[0036] Connect a control unit to the first transparent conductive electrode and the second transparent conductive electrode, wherein the control unit is configured to provide at least a first scenario and a second scenario, in the first scenario, all the second partitions receive the same electrical signal and at least two first partitions receive different electrical signals, and in the second scenario, all the first partitions receive the same electrical signal and at least two second partitions receive different electrical signals.

[0037] Using this method, the etching of the conductive electrodes is carried out directly on the prepared film, rather than on individual electrode parts. In addition, with this method, there is no need to precisely adjust the two electrodes together during the process of laminating the PDLC film, which is both time-consuming and generates waste. In this case, since the electrodes are already installed and thus automatically aligned, such complex operations are not required.

[0038] Another advantage is that since the risk of contamination is eliminated, there is no need to provide a clean room environment.

[0039] Finally, the etching operation is cleaner, faster, more environmentally friendly (saving a large amount of waste, not requiring a clean room, and saving a large amount of energy during this process), and more economical compared to etching each conductive layer separately.

[0040] In some specific embodiments, the method further includes a step of rotating the prepared film between the step of etching the first transparent conductive electrode and the step of etching the second transparent conductive electrode.

[0041] By this step, the same picosecond ultraviolet laser device can be used to operate on both sides, and the rotating mechanism can be calibrated to precisely perform the etching operation.

[0042] In some specific embodiments, the shape of at least one second partition in the second partitions is different from the shape of at least one first partition in the first partitions.

[0043] When each side has a different pattern, the same final product can be used to create different patterns. Description of the Drawings

[0044] To complete the description and better understand the present invention, a set of drawings is provided. The drawings form an essential part of the specification and illustrate embodiments of the present invention, which should not be construed as limiting the scope of the present invention, but only as examples of how the present invention may be implemented. The drawings include the following figures:

[0045] Figure 1 A schematic diagram showing a first embodiment of a membrane device according to the present invention.

[0046] Figure 2 A perspective view showing such a membrane device.

[0047] Figure 3 Shows different perspective views of such a membrane device.

[0048] Figure 4 And Figure 5 Shows different operating scenarios of such a membrane device.

[0049] The reference numerals used in the drawings are as follows:

[0050] 1 First transparent electrode

[0051] 2 Second transparent electrode

[0052] 3 Active optical material

[0053] 4 PET sheet

[0054] 5 PET sheet

[0055] 6 Control unit

[0056] 11 - 19 First partition

[0057] 21 - 23 Second partition Detailed description of the specific implementation

[0058] The exemplary embodiments are described in sufficient detail so that those of ordinary skill in the art can implement and realize the systems and processes described in the present invention. It is important to understand that the embodiments may be provided in many alternative forms and should not be construed as limited to the examples described in the present invention.

[0059] Accordingly, although the embodiments may be modified in various ways and take various alternative forms, specific embodiments thereof are shown in the drawings and described in detail below as examples. It is not intended to be limited to the specific forms disclosed herein. On the contrary, all modifications, equivalents, and alternatives within the scope of the appended claims should be included. In the drawings and the detailed description, elements of the exemplary embodiments are always denoted by the same reference numerals where appropriate.

[0060] Figure 1Schematic diagram showing a first embodiment of a membrane device according to the present invention.

[0061] In this schematic diagram, the membrane device includes a first transparent electrode 1, a second transparent electrode 2, and an active optical material 3 disposed between the first transparent electrode 1 and the second transparent electrode 2. The active optical material 3 is in direct contact with the first transparent electrode 1 and the second transparent electrode 2.

[0062] The optical properties of such an active optical material are determined by the voltage it receives. When the received voltage exceeds a predefined threshold, the transparency of the material changes.

[0063] In some cases, the material is opaque when no voltage is applied and changes from opaque to transparent when a voltage is applied between the two sides. In other cases (referred to as "reverse mode cases"), the material is transparent when no voltage is applied and changes from transparent to opaque when a voltage is applied between the two sides.

[0064] Although different materials may be used in other embodiments belonging to the present invention, in this specific embodiment, the active optical material 3 is polymer dispersed liquid crystal (PDLC). In addition, the transparent electrodes are indium tin oxide (ITO), although in other cases, other types of transparent electrodes (such as silver nanowires, AgNW) may be used.

[0065] Each transparent electrode is placed on PET sheets 4, 5. Thus, for example, this structure can be installed in the partitions of an office. However, in other embodiments, these electrodes can be installed in other substrates, such as glass plates, so that this structure can be installed in a house (in a door or in a window).

[0066] In this figure, it can also be seen how the first transparent electrode 1 is divided into first partitions 11 - 19. Although 9 first partitions are shown in this figure, it is only a general example. These element partitions are obtained by etching, which is usually done by laser cutting. The end result is that each first partition is electrically independent - although there may be additional connections between some of these partitions - to create partition groups.

[0067] Correspondingly, the second transparent electrode 2 is also divided into second partitions 21 - 23. These partitions are obtained by etching, which is usually done by laser cutting. The end result is that each second partition is electrically independent - although there may be additional connections between some of these partitions - to create partition groups. Again, although only three second partitions are shown, any number of second partitions can be implemented in different embodiments.

[0068] The electrical signal is provided by the control unit 6 to each partition. The control unit 6 receives the standard alternating current voltage, converts it into a direct current voltage, and then into an alternating square wave with or without a phase shift.

[0069] This drawing is simplified for the purpose of understanding the present invention, as there may be dozens of different partitions in a real product, as shown below.

[0070] Figure 2 An embodiment of the first scenario using such an optical device is shown.

[0071] In this first scenario, all the second segments are fed the same signal S1, so they operate as a single electrode.

[0072] Different groups of first segments are fed different phase-shifted signals. For example, the first group of first segments is fed a second signal S2 that is offset by 45° with respect to the first signal S1 fed to the second segments.

[0073] As a result, the corresponding partitions are activated only during 25% of the period of the wave (where waves S1 and S2 provide different values, so there is a transparency value of 25% in the corresponding partitions).

[0074] The second group of first segments is fed a third signal S3 that is offset by 135° with respect to the first signal S1 fed to the second segments.

[0075] As a result, the corresponding partitions are activated only during 75% of the period of the wave (where waves S1 and S3 provide different values, so there is a transparency value of 75% in the corresponding partitions).

[0076] Finally, the third group of first segments is fed a third signal S4 that is offset by 0° with respect to the first signal S1 fed to the second segments.

[0077] As a result, the corresponding partitions are never activated during the period of the wave (waves S1 and S4 never provide different values, so the voltage value in the corresponding partitions is 0).

[0078] Figure 3 and Figure 4 Examples of this operation are shown by referring to different embodiments of the first scenario.

[0079] As can be seen from these figures, the first partition is defined in the shape of a tree trunk contour. In this figure, there are nine different groups, although in different examples, any number of groups is possible.

[0080] In this first scenario, since all segments of the second transparent electrode are provided with the same electrical signal, all segments of the second transparent electrode operate as a single electrode. Thus, the pattern to be seen will be defined by different signals provided to each of the first partitions.

[0081] According to the figure above, some trees will be fed signal S2, some trees will be fed signal S3, and some trees will be fed signal S4. More signals can be used for other trees, but these three signals are sufficient to illustrate the present invention.

[0082] Thus, each tree will have a different transparency level (the tree fed with signal S2 will have 25% transparency, the tree fed with signal S3 will have 75% transparency, and the tree fed with signal S4 will be opaque).

[0083] Figure 4 The same embodiment is shown, but with the signals provided to each group changed (for example, Figure 2 the trees that received signal S2 in now receive signal S3, and so on).

[0084] Therefore, through dynamic control, patterns of changes in the transparency (shading) of each group of trees can be gradually generated in thousands of different combinations. By exploiting these differences, different levels can be achieved by moving the rear trees to the front and the front trees to the rear, and vice versa, thus creating a dynamic artistic landscape. This effect can be continued or stopped as desired by the user through an application installed on the user's mobile phone or tablet.

[0085] Figure 5 An optical device in the same but second scenario is shown. Here, all first partitions are fed the same common electrical signal, while the second partitions are fed different electrical signals. Now, the pattern is defined by the second partitions, which is completely different from the first partitions. In this figure, it can be seen that many different effects can be achieved using this device.

[0086] The prominent advantage of this device is that since the two conductive elements are transparent, different effects can be seen from each of the two sides of the same piece of glass: the same piece of glass seen from the same side can provide a circular pattern or a tree pattern. Needless to say, these two patterns can be complex according to design requirements, and the examples shown in these figures are deliberately simplified for clarity and ease of understanding of the present invention.

[0087] Figure 6 Some steps of a method according to the present invention are shown, which method is applicable to manufacturing the product as described in the previous figure.

[0088] In this figure, a first transparent conductive electrode 1, a second transparent conductive electrode 2, and a PDLC film 3 are provided. The PDLC film 3 is configured to change at least one optical property when a voltage is applied, and includes a first surface and a second surface, the second surface being opposite to the first surface.

[0089] The first transparent conductive electrode 1 is attached to the first surface of the PDLC film 3, and the second transparent conductive electrode 2 is attached to the second surface of the active optical material 3, thereby obtaining a prepared film.

[0090] Figure 7a and Figure 7b Some additional steps of the method are shown. First, the first transparent conductive electrode 1 is etched into first partitions, each first partition being electrically isolated from the rest of the first partitions. The etching process is completed by a picosecond ultraviolet laser device 20.

[0091] Then, the prepared film is rotated and the second transparent conductive electrode 2 is etched into second partitions, each second partition being electrically isolated from the rest of the second partitions. These shapes are different from the shapes of the first partitions. This etching process is also completed by the picosecond ultraviolet laser device 20.

[0092] Finally, a control unit is connected to the first transparent conductive electrode and the second transparent conductive electrode. The control unit is configured to provide at least a first scenario and a second scenario. In the first scenario, all the second partitions receive the same electrical signal and at least two first partitions receive different electrical signals. In the second scenario, all the first partitions receive the same electrical signal and at least two second partitions receive different electrical signals.

Claims

1. An optical device, comprising a first transparent conductive electrode (1), a second transparent conductive electrode (2), and an active optical material (3), wherein the active optical material (3) is disposed between the first transparent conductive electrode (1) and the second transparent conductive electrode (2) and is in electrical contact with the first transparent conductive electrode (1) and the second transparent conductive electrode (2). Wherein, the active optical material (3) is configured to change at least one optical property when a voltage is applied thereto; wherein the first transparent conductive electrode (1) is divided into first partitions (11 - 15), and each first partition is electrically isolated from the remaining first partitions in the first partitions (11 - 15); wherein the second transparent conductive electrode (2) is divided into second partitions (21, 22, 23), and each second partition is electrically isolated from the remaining second partitions in the second partitions (21, 22, 23); wherein the optical device further comprises a control unit (6), the control unit (6) being configured to provide electrical signals to each first partition in the first partitions (11 - 15) and each second partition in the second partitions (21 - 23), wherein the control unit (6) is configured to provide at least a first scenario and a second scenario, in the first scenario, all the second partitions receive the same electrical signal and at least two first partitions receive different electrical signals, and in the second scenario, all the first partitions receive the same electrical signal and at least two second partitions receive different electrical signals.

2. The optical device according to claim 1, wherein, the control unit (6) includes a first element configured to receive a sinusoidal alternating current and convert it into a direct current signal, and includes a second element configured to convert the direct current signal into an alternating square wave, and includes a third element configured to generate a phase shift signal according to the square wave and feed the phase shift signal to the first partitions and the second partitions.

3. The optical device according to any one of the preceding claims, wherein, the thickness of the active optical material (3) is from 5 microns to 100 microns.

4. The optical device according to any one of the preceding claims, wherein, the first transparent conductive electrode (1) and / or the second transparent conductive electrode (2) includes indium tin oxide, silver nanowires, carbon nanotubes, graphene, a transparent conductive polymer, or nano - metal.

5. The optical device according to any one of the preceding claims, wherein, the first transparent conductive electrode (1) is disposed on a first transparent substrate (4) and / or the second transparent conductive electrode (2) is disposed on a second transparent substrate (5).

6. The optical device according to claim 5, wherein, the first transparent substrate (4) and / or the second transparent substrate (5) includes glass.

7. The optical device according to claim 5, wherein, the first transparent substrate (4) and / or the second transparent substrate (5) includes a plastic film made of polyethylene terephthalate.

8. The optical device according to any one of claims 5 to 7, wherein, The first transparent substrate (4) and / or the second transparent substrate (5) comprises an infrared coating.

9. The optical device according to any one of the preceding claims, wherein, the active optical material (3) comprises polymer dispersed liquid crystal.

10. The optical device according to any one of claims 1 to 7, wherein, the active optical material (3) comprises black dichroic dye polymer dispersed liquid crystal.

11. A method for manufacturing an optical device according to any one of the preceding claims, comprising the steps of: providing a first transparent conductive electrode (1), a second transparent conductive electrode (2) and an active optical material (3), wherein the active optical material (3) is configured to change at least one optical property when a voltage is applied, and the active optical material (3) comprises a first face and a second face opposite to the first face; attaching the first transparent conductive electrode (1) to the first face of the optical material (3) and attaching the second transparent conductive electrode (2) to the second face of the active optical material (3) to obtain a prepared film; etching the first transparent conductive electrode (1) into first partitions (11 - 15), each first partition being electrically isolated from the remaining partitions of the first partitions (11 - 15), wherein the etching process is completed by means of a picosecond ultraviolet laser device (20); etching the second transparent conductive electrode (2) into second partitions (21, 22, 23), each second partition being electrically isolated from the remaining partitions of the second partitions (21, 22, 23), wherein the etching process is completed by means of a picosecond ultraviolet laser device (20); connecting a control unit (6) to the first transparent conductive electrode and the second transparent conductive electrode, wherein the control unit (6) is configured to provide at least a first scenario and a second scenario, in the first scenario, all the second partitions receive the same electrical signal and at least two first partitions receive different electrical signals, and in the second scenario, all the first partitions receive the same electrical signal and at least two second partitions receive different electrical signals.

12. The method according to claim 11, further comprising the step of rotating the prepared film between the step of etching the first transparent conductive electrode and the step of etching the second transparent conductive electrode.

13. The method according to any one of claims 11 or 12, wherein the shape of at least one of the second partitions is different from the shape of at least one of the first partitions.

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