Double-layer dye liquid crystal film and liquid crystal dimming device thereof
By using a double-layer dye liquid crystal film structure and employing spirally arranged liquid crystal molecules and optically transparent adhesive bonding technology, the problem of low contrast in liquid crystal films is solved, achieving a dimming effect with high contrast and low haze.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHENZHEN WICUE OPTOELECTRONICS CO LTD
- Filing Date
- 2025-01-14
- Publication Date
- 2026-04-10
AI Technical Summary
Existing liquid crystal films have low contrast ratios and unsatisfactory dimming effects. In particular, the contrast ratio of dye liquid crystal technology is below 40, which is insufficient to meet the high requirements of optical performance.
The structure employs a dual-layer dye liquid crystal film, comprising a first liquid crystal unit and a second liquid crystal unit stacked together. The liquid crystal molecules within each liquid crystal unit are arranged in a spiral shape, and the two liquid crystal layers are bonded together with an optically transparent adhesive to improve contrast.
The contrast ratio of the liquid crystal film has been significantly improved to 50-450, with dark state haze less than 5% and bright state haze less than 2%, achieving a high-contrast dimming effect.
Smart Images
Figure CN224109761U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of liquid crystal dimming, in particular to a double-layer dye liquid crystal film and a liquid crystal dimming device thereof. BACKGROUND
[0002] The liquid crystal film generally comprises a pair of transparent electrode layers and a liquid crystal layer between the electrode layers, the liquid crystal molecules in the liquid crystal layer can change with the change of the applied electric field due to their arrangement mode, and have electric response characteristics; the liquid crystal molecules arranged in a certain degree of order by surface orientation or the like have the function of modulating the light passing through the inside thereof, and have light modulation characteristics.
[0003] Due to the electric response and light modulation characteristics of the liquid crystal material, the liquid crystal material has been widely used in the display field since the 1960s-1970s. At present, the liquid crystal film has been widely applied to building curtain walls, partitions, automobile canopies, side windows, dimming glasses, virtual reality glasses and other products and optical devices requiring light modulation function.
[0004] The application of the liquid crystal film in the market is more and more, and the requirements for the optical properties of the liquid crystal film such as haze, color, transmittance range, contrast ratio and the like, especially the bright-dark contrast ratio, are higher and higher.
[0005] At present, four types of dimming technologies have been put on the market: polymer dispersed liquid crystal technology (Polymer Dispersed Liquid Crystal, PDLC), suspended particle technology (Suspended-particle devices, SPD), electrochromic technology (Electrochromic, EC) and dye liquid crystal technology (Dye Liquid Crystal, DLC). The bright-dark contrast ratio (the contrast ratio is defined as the ratio of the bright state transmittance to the dark state transmittance) of the above four dimming technologies is basically within 40, the contrast ratio is low, the bright-dark change is not obvious, and the dimming sensory effect is not ideal.
[0006] For the DLC technology, the liquid crystal layer of the liquid crystal film is a guest-host (Guest-Host, GH) type dye-liquid crystal prepared by mixing dichroic dye molecules and liquid crystal molecules. Because the dye itself has absorption in a certain waveband of visible light, the GH type dye-liquid crystal can adjust the light transmittance in a certain color. In view of the problem of low contrast ratio existing in the DLC technology, a double-box dye liquid crystal structure is appeared, which comprises two layers of dye liquid crystal films, the transmittance range is 1%-35%, and the contrast ratio is close to 40. This contrast ratio is still not high, and the dimming effect is not ideal. CONTENT OF THE INVENTION
[0007] In view of the above technical problems, the present application provides a double-layer dye liquid crystal film with high contrast ratio.
[0008] In one aspect of the present application, a double-layer dye liquid crystal film is provided, which comprises a first liquid crystal unit and a second liquid crystal unit arranged in a stack, the first liquid crystal unit comprising a first liquid crystal layer, and the second liquid crystal unit comprising a second liquid crystal layer.
[0009] The first liquid crystal layer comprises first liquid crystal molecules, first dye molecules and first chiral agent molecules, the first chiral agent molecules being capable of making the first liquid crystal molecules helically twisted in space; and the second liquid crystal layer comprises second liquid crystal molecules, second dye molecules and second chiral agent molecules, the second chiral agent molecules being capable of making the second liquid crystal molecules helically twisted in space.
[0010] The double-layer dye liquid crystal film of the present application comprises a first liquid crystal layer and a second liquid crystal layer. Firstly, the first / second liquid crystal molecules in the first / second liquid crystal layer alone are helically twisted in the whole, which improves the contrast of the single-layer first / second liquid crystal layer. Secondly, the double-layer dye liquid crystal film of the present application further improves the contrast by using two liquid crystal layers arranged in a stack.
[0011] Preferably, the thickness of the first liquid crystal unit is D1, the liquid crystal pitch of the first liquid crystal molecules is P1, the thickness of the second liquid crystal unit is D2, and the liquid crystal pitch of the second liquid crystal molecules is P2, and the ratio of D1:P1 and / or D2:P2 is in the range of 1.5-5.0.
[0012] Preferably, the light transmittance of the first liquid crystal unit and / or the second liquid crystal unit is in the range of any one of 6%-46%, 1.5%-30% and 3%-38%.
[0013] Preferably, the first liquid crystal unit and the second liquid crystal unit arranged in a stack are bonded by an optically transparent adhesive.
[0014] Preferably, the contrast of the double-layer dye liquid crystal film is in the range of 50-450.
[0015] Preferably, the haze of the double-layer dye liquid crystal film in a dark state is less than 5%, and the haze of the double-layer dye liquid crystal film in a bright state is less than 2%.
[0016] Preferably, the thickness of the double-layer dye liquid crystal film is in the range of 0.8mm-1.0mm.
[0017] In another aspect of the present application, a liquid crystal dimming device is provided, which comprises two transparent substrate layers arranged oppositely and a double-layer dye liquid crystal film as described above arranged between the two transparent substrate layers.
[0018] Preferably, the double-layer dye liquid crystal film and the two transparent substrate layers are bonded by an optically transparent adhesive.
[0019] Compared with the prior art, the beneficial effects of the technical scheme of the present application are that the double-layer dye liquid crystal film of the present application comprises a first liquid crystal layer and a second liquid crystal layer. Firstly, for the first liquid crystal layer or the second liquid crystal layer alone, the first / second liquid crystal molecules inside are arranged in a spiral twist type as a whole, thereby improving the contrast of the single-layer first / second liquid crystal layer. Secondly, the double-layer dye liquid crystal film of the present application further improves its contrast in the state of two-layer liquid crystal layer superposition. BRIEF DESCRIPTION OF DRAWINGS
[0020] Figure 1 FIG. 1 is a structural schematic diagram of a double-layer dye liquid crystal film in an embodiment of the present application;
[0021] Figure 2 FIG. 2 is a structural schematic diagram of a single-layer liquid crystal unit in an embodiment of the present application;
[0022] Figure 3 FIG. 3 is a structural schematic diagram of a liquid crystal dimming device in an embodiment of the present application.
[0023] FIG. 1 is a structural schematic diagram of a double-layer dye liquid crystal film in an embodiment of the present application; FIG. 2 is a structural schematic diagram of a single-layer liquid crystal unit in an embodiment of the present application; FIG. 3 is a structural schematic diagram of a liquid crystal dimming device in an embodiment of the present application; and FIG. 4 is a structural schematic diagram of a liquid crystal dimming device in another embodiment of the present application. DETAILED DESCRIPTION
[0024] The schemes in the embodiments of the present application will be described in detail below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.
[0025] As described in the background, the application of dye liquid crystal film is more and more extensive, and its transmittance range and corresponding contrast performance are also more and more valued by people.
[0026] The dye molecules and liquid crystal molecules in the liquid crystal layer of the dye liquid crystal film are mixed to form a guest-host type dye liquid crystal, which has a modulation function for light passing through the inside, so that the dye liquid crystal film has different transmittance.
[0027] Among them, the anisotropic dye molecules align with the alignment of the liquid crystal molecules to exhibit anisotropic light absorption properties with respect to the direction of the orientation of the anisotropic dye molecules and the direction perpendicular to the direction of the orientation. In the present specification, the term "dye" refers to a material that can strongly absorb and / or convert light in some or all of the visible light region (for example, a wavelength range of 400 nm to 700 nm), and the term "anisotropic dye" refers to a material that can allow anisotropic absorption of light in some or all of the visible light region. For example, anisotropic dyes are selected to have dye molecules that are oriented according to the orientation state of the liquid crystal molecules, such dye molecules include azo dyes or anthraquinone dyes known in the related art, but are not limited thereto. The dichroic ratio of the anisotropic dye commonly referred to is a value obtained by dividing the absorption of polarized light parallel to the long axis direction of the anisotropic dye by the absorption of polarized light parallel to the direction perpendicular to the long axis direction.
[0028] For example, the dichroic dye molecules are materials whose degree of absorption of light varies depending on the polarization direction, and thus when the dye molecules have a high degree of absorption of light polarized in the long axis direction, they can be referred to as p-type dyes, and when the dye molecules have a high degree of absorption of light polarized in the short axis direction, they can be referred to as n-type dyes. When p-type dyes are used, polarized light vibrating in the long axis direction of the dye molecules can be absorbed, and polarized light vibrating in the short axis direction of the dye molecules can be transmitted, which is poorly absorbed. The dye liquid crystal layer can adjust the orientation of the liquid crystal molecules and the dichroic dye molecules to adjust the anisotropic light absorption with respect to polarized light in the direction parallel to the orientation direction of the dichroic dye molecules and polarized light in the perpendicular direction. Since the orientation of the liquid crystal molecules and the dichroic dye molecules can be adjusted by applying an external action (for example, a magnetic field or an electric field), the dye liquid crystal layer can adjust the anisotropic light absorption according to the application of the external action.
[0029] For the liquid crystal molecules, liquid crystal molecules whose alignment state can be switched upon application of a voltage can be appropriately selected. For example, nematic liquid crystals, which refer to liquid crystals oriented parallel to the long axis direction of rod-shaped liquid crystal molecules, can be used.
[0030] In the present specification, the transmittance range of the dye liquid crystal film is designed to be between a relatively high transmittance state (transmission state or bright state) and a relatively low transmittance state (cut-off state or dark state). The value of the transmittance is desired to be higher in the bright state, and the value of the transmittance is desired to be lower in the dark state. The transmittance range of a typical single-layer dye liquid crystal film is 6% to 46% or 1.5% to 30%, and the contrast ratio is ≤ 20, where the contrast ratio is defined as the ratio of the bright state transmittance to the dark state transmittance.
[0031] To further improve the dimming effect and obtain a high-contrast dye liquid crystal film, the inventors of the present application creatively propose a double-layer dye liquid crystal film 100, which comprises a first liquid crystal unit 101 and a second liquid crystal unit 102 arranged in a stack, the first liquid crystal unit 101 comprises a first liquid crystal layer 1011, and the second liquid crystal unit 102 comprises a second liquid crystal layer 1021; the first liquid crystal layer 1011 comprises first liquid crystal molecules, first dye molecules and first chiral agent molecules, and the first chiral agent molecules can make the first liquid crystal molecules present in a spiral shape in space; the second liquid crystal layer 1021 comprises second liquid crystal molecules, second dye molecules and second chiral agent molecules, and the second chiral agent molecules can make the second liquid crystal molecules present in a spiral shape in space.
[0032] In the embodiments of the present application, the first liquid crystal unit 101 and the second liquid crystal unit 102 overlap with each other in space, and the light passing through the first liquid crystal unit 101 can be incident on the second liquid crystal unit 102, or the light passing through the second liquid crystal unit 102 can also be incident on the first liquid crystal unit 101. Figure 1 is a structural schematic view schematically showing the first liquid crystal unit 101 and the second liquid crystal unit 102 overlapping with each other.
[0033] In addition to containing the liquid crystal layer, the first liquid crystal unit 101 and / or the second liquid crystal unit 102 can also include a substrate layer, a conductive layer and an alignment layer, etc. The specific structure of the first liquid crystal unit 101 and the second liquid crystal unit 102 is not limited herein. For example, the first liquid crystal unit 101 and the second liquid crystal unit 102 can each further include two alignment films (not shown in the figure) arranged on both sides of the first liquid crystal layer 1011 and the second liquid crystal layer 1021; the first liquid crystal unit 101 can sequentially include a first vertical alignment film, the first liquid crystal layer 1011 and a second vertical alignment film, and the second liquid crystal unit 102 can sequentially include a third vertical alignment film, the second liquid crystal layer 1021 and a fourth vertical alignment film.
[0034] The first liquid crystal unit 101 and the second liquid crystal unit 102 include a structure of two guest-host liquid crystal layers, and the orientation of the respective dichroic dye molecules in the first liquid crystal layer 1011 and the second liquid crystal layer 1021 can be adjusted respectively, so as to switch between the bright state and the dark state. The first liquid crystal layer 1011 and the second liquid crystal layer 1021 can be switched between the vertical alignment state and the horizontal alignment state according to different applied voltages. For example, the liquid crystal molecules in the vertical alignment state when no voltage is applied can be switched to the horizontal alignment state by applying a voltage to the liquid crystal layer; or the liquid crystal molecules in the horizontal alignment state can be switched to the vertical alignment state by applying a voltage to the liquid crystal layer.
[0035] For the design of the single-layer liquid crystal cell (only the first liquid crystal cell 101 is taken as an example below, and the second liquid crystal cell 102 has a similar situation), the first liquid crystal layer 1011 of the first liquid crystal cell 101 contains chiral agent molecules, and the amount of the chiral agent molecules added can be represented as C = 1 / HTP*P, where C represents the amount of the chiral agent molecules added, HTP represents the twist ability of the liquid crystal molecules (for a specific liquid crystal molecule, HTP is a specific value), and P represents the liquid crystal pitch. As can be seen from the above relationship, for a selected liquid crystal molecule, the liquid crystal pitch P of the liquid crystal molecule can be adjusted by changing the amount of the chiral agent molecules added in the first liquid crystal layer 1011. At the same time, by controlling the thickness D1 of the first liquid crystal cell 101, a film with a large difference between the transmittance in the bright state and the transmittance in the dark state, i.e., a film with a high contrast ratio, can be achieved. The ratio D1:P1 between the thickness D1 of the first liquid crystal cell 101 and the liquid crystal pitch P1 not only relates to the contrast ratio of the first liquid crystal cell 101, but also affects the haze of the first liquid crystal cell 101. In the embodiments of the present application, the range of the liquid crystal pitch P1 is limited to 2um-8um, the range of D1 is designed to be 6um-12um, and finally the range of D1:P1 is 1.5-5.0. In this way, the contrast ratio of the first liquid crystal cell 101 can be greater than 7 and the haze can be less than 3.
[0036] The transmittance range of the first liquid crystal cell 101 and / or the second liquid crystal cell 102 can be designed to be any one of 6%-46%, 1.5%-30%, and 3%-38%.
[0037] The first liquid crystal cell 101 and the second liquid crystal cell 102 which are spatially overlapped can be bonded by an optical clear adhesive (OCA) or by a middle film hot lamination process. Similarly, for the high-contrast double-layer dye liquid crystal film 100 manufactured, it can be arranged between the oppositely arranged double-sided glass (or other transparent hard / flexible materials), and bonded by OCA or other lamination processes to manufacture a liquid crystal dimming device 200; in addition, the high-contrast double-layer dye liquid crystal film 100 can also be directly attached to the building glass outer wall, vehicle window, lens and other application scenarios that need to be applied. The thickness of the high-contrast double-layer dye liquid crystal film 100 of the present application is about 0.8mm-1.0mm, and at the same time, it can be manufactured into a flexible and bendable structure, and has the characteristics of lightness, which can meet the dimming film requirements in various complex application scenarios.
[0038] The specific embodiments of the present application will be described below in conjunction with the accompanying drawings, but the present application is not limited to the embodiments disclosed below.
[0039] Embodiment 1
[0040] As Figure 1As shown, a double-layer dye liquid crystal film 100 includes a first liquid crystal unit 101 and a second liquid crystal unit 102 arranged in a stack, and the first liquid crystal unit 101 and the second liquid crystal unit 102 are bonded by OCA.
[0041] As shown, the first liquid crystal unit 101 includes a first liquid crystal layer 1011, and the first liquid crystal layer 1011 includes first liquid crystal molecules, first dye molecules, and first chiral agent molecules, and the first chiral agent molecules can make the first liquid crystal molecules helically in space; here, only the structure of the first liquid crystal unit 101 is exemplified, and the structure of the second liquid crystal unit 102 is similar to that of the first liquid crystal unit 101. Figure 2
[0042] In this embodiment, the thickness D1 of the first liquid crystal unit 101 is 6um, the liquid crystal pitch P1 is 2.5um, D1:P1 is 2.4; the haze of the first liquid crystal unit 101 is less than 3. The thickness D2 of the second liquid crystal unit 102 is 6um, the liquid crystal pitch P2 is 2.5um, D2:P2 is 2.4; the haze of the second liquid crystal unit 102 is less than 3. The transmittance of the first liquid crystal unit 101 is 6%-46%, the transmittance of the second liquid crystal unit 102 is 6%-46%, the transmittance of the double-layer dye liquid crystal film 100 made is 0.36%-21.2%, the contrast is 59, and the haze of the double-layer dye liquid crystal film 100 in a dark state is less than 5%, and the haze in a bright state is less than 2%.
[0043] Embodiment 2
[0044] Compared with Embodiment 1, the basic structure of this embodiment is the same, and the difference is that:
[0045] In Embodiment 2, the thickness D1 of the first liquid crystal unit 101 is 6um, the liquid crystal pitch P1 is 2.5um, D1:P1 is 2.4; the haze of the first liquid crystal unit 101 is less than 3. The thickness D2 of the second liquid crystal unit 102 is 12um, the liquid crystal pitch P2 is 3um, D2:P2 is 4; the haze of the second liquid crystal unit 102 is less than 3. The transmittance of the first liquid crystal unit 101 is 6%-46%, the transmittance of the second liquid crystal unit 102 is 1.5%-30%, the transmittance of the double-layer dye liquid crystal film 100 made is 0.09%-13.8%, the contrast is 153, and the haze of the double-layer dye liquid crystal film 100 in a dark state is less than 5%, and the haze in a bright state is less than 2%.
[0046] Embodiment 3
[0047] Compared with Embodiment 1, the basic structure of this embodiment is the same, and the difference is that:
[0048] In Example 3, the thickness D1 of the first liquid crystal cell 101 is 6 um, the liquid crystal pitch P1 is 2.5 um, D1:P1 is 2.4, and the haze of the first liquid crystal cell 101 is less than 3. The thickness D2 of the second liquid crystal cell 102 is 9 um, the liquid crystal pitch P2 is 2.8 um, D2:P2 is 3.2, and the haze of the second liquid crystal cell 102 is less than 3. The transmittance of the first liquid crystal cell 101 is 6%-46%, the transmittance of the second liquid crystal cell 102 is 3%-38%, the transmittance of the double-layer dye liquid crystal film 100 prepared is 0.18%-17.5%, the contrast is 97, the haze of the double-layer dye liquid crystal film 100 in a dark state is less than 5%, and the haze of the double-layer dye liquid crystal film 100 in a bright state is less than 2%.
[0049] Example 4
[0050] The basic structure of this example is the same as that of Example 1, except that:
[0051] In Example 4, the thickness D1 of the first liquid crystal cell 101 is 12 um, the liquid crystal pitch P1 is 3 um, D1:P1 is 4, and the haze of the first liquid crystal cell 101 is less than 3. The thickness D2 of the second liquid crystal cell 102 is 12 um, the liquid crystal pitch P2 is 3 um, D2:P2 is 4, and the haze of the second liquid crystal cell 102 is less than 3. The transmittance of the first liquid crystal cell 101 is 1.5%-30%, the transmittance of the second liquid crystal cell 102 is 1.5%-30%, the transmittance of the double-layer dye liquid crystal film 100 prepared is 0.02%-9%, the contrast is 400, the haze of the double-layer dye liquid crystal film 100 in a dark state is less than 5%, and the haze of the double-layer dye liquid crystal film 100 in a bright state is less than 2%.
[0052] Example 5
[0053] The basic structure of this example is the same as that of Example 1, except that:
[0054] In Example 5, the thickness D1 of the first liquid crystal cell 101 is 12 um, the liquid crystal pitch P1 is 3 um, D1:P1 is 4, and the haze of the first liquid crystal cell 101 is less than 3. The thickness D2 of the second liquid crystal cell 102 is 9 um, the liquid crystal pitch P2 is 2.8 um, D2:P2 is 3.2, and the haze of the second liquid crystal cell 102 is less than 3. The transmittance of the first liquid crystal cell 101 is 1.5%-30%, the transmittance of the second liquid crystal cell 102 is 3%-38%, the transmittance of the double-layer dye liquid crystal film 100 prepared is 0.04%-11.4%, the contrast is 253, the haze of the double-layer dye liquid crystal film 100 in a dark state is less than 5%, and the haze of the double-layer dye liquid crystal film 100 in a bright state is less than 2%.
[0055] Example 6
[0056] The basic structure of this example is the same as that of Example 1, except that:
[0057] In Example 6, the thickness D1 of the first liquid crystal cell 101 is 9 um, the liquid crystal pitch P1 is 2.8 um, D1:P1 is 3.2; the haze of the first liquid crystal cell 101 is less than 3. The thickness D2 of the second liquid crystal cell 102 is 9 um, the liquid crystal pitch P2 is 2.8 um, D2:P2 is 3.2; the haze of the second liquid crystal cell 102 is less than 3.
[0058] The transmittance of the first liquid crystal cell 101 is 3%-38%, the transmittance of the second liquid crystal cell 102 is 3%-38%, the transmittance of the double-layer dye liquid crystal film 100 prepared is 0.09%-14.4%, the contrast ratio is 160, and the haze of the dark state of the double-layer dye liquid crystal film 100 is less than 5%, the bright state haze is less than 2%.
[0059] Example 7
[0060] As shown in Figure 3 A light-adjusting device 200 includes transparent glass, a double-layer dye liquid crystal layer 100 and transparent glass which are stacked in sequence, and the double-layer dye liquid crystal film 100 is bonded between the upper glass and the lower glass by OCA.
[0061] In another aspect, for the double-layer dye liquid crystal film 100 of the present application, an exemplary preparation method is as follows: first, using a conductive substrate, a plurality of functional layers (such as an orientation layer) are integrated on the conductive substrate by a roll-to-roll process, and uniform support and edge sealing are achieved on the functional layer, and at the same time, the helical twisted dye liquid crystal material is uniformly encapsulated between the two layers of conductive substrate, then through post-processing, a single-layer dye liquid crystal film piece with complete encapsulation is made; finally, through the middle film hot laminating process or OCA attachment, two single-layer dye liquid crystal film pieces are made into a double-layer dye liquid crystal film 100.
[0062] As a transparent conductive substrate, for example, a conductive substrate layer can be formed by depositing a conductive polymer, a conductive metal, a conductive nanowire or a metal oxide (such as Indium Tin Oxide, ITO). In addition, the substrate capable of forming a transparent conductive substrate layer is known in the related art, which is not limited herein.
[0063] The double-layer dye liquid crystal film 100 of the present application includes a first liquid crystal layer 1011 and a second liquid crystal layer 1021, first for the first liquid crystal layer 1011 or the second liquid crystal layer 1021 alone, the first / second liquid crystal molecules inside are arranged in a helical twisted manner as a whole, which improves the contrast ratio of the single-layer first / second liquid crystal layer; at the same time, the D:P value of the single-layer first / second liquid crystal cell is limited to make the single-layer dye liquid crystal film piece have high contrast ratio and low haze.
[0064] Secondly, the double-layer dye liquid crystal film 100 of the present application further improves its contrast ratio in a state of two liquid crystal layers being stacked. The double-layer dye liquid crystal film 100 with variable transmittance can be applied to various occasions, including various materials for buildings or vehicles that need to control transmittance, or eyewear, such as sports or experience augmented reality goggles, sunglasses, helmets, etc.
[0065] The above examples are only used to illustrate the specific embodiments of the present application, and it should be pointed out that for those skilled in the art, various modifications and changes can be made without departing from the concept of the present application, and these modifications and changes should also belong to the protection scope of the present application.
Claims
1. A dual-layer dye liquid crystal film, characterized by, The first liquid crystal unit comprises a first liquid crystal layer, and the second liquid crystal unit comprises a second liquid crystal layer; The first liquid crystal layer comprises first liquid crystal molecules, first dye molecules and first chiral agent molecules, and the second liquid crystal layer comprises second liquid crystal molecules, second dye molecules and second chiral agent molecules; The thickness of the first liquid crystal unit is D1, the liquid crystal pitch of the first liquid crystal molecules is P1, and the ratio of D1 to P1 ranges from 1.5 to 5.
0. The thickness of the second liquid crystal unit is D2, the liquid crystal pitch of the second liquid crystal molecules is P2, and the ratio of D2 to P2 ranges from 1.5 to 5.
0.
2. The dual-layer dye liquid crystal film according to claim 1, characterized in that, The transmittance of the first liquid crystal unit ranges from any one of 6% to 46%, 1.5% to 30% and 3% to 38%.
3. The dual-layer dye liquid crystal film according to claim 1, characterized in that, The transmittance of the second liquid crystal unit ranges from any one of 6% to 46%, 1.5% to 30% and 3% to 38%.
4. The dual-layer dye liquid crystal film according to claim 1, characterized in that, The first liquid crystal unit and the second liquid crystal unit are adhered by an optical transparent adhesive.
5. The dual-layer dye liquid crystal film according to claim 1, wherein The contrast ratio of the double-layer dye liquid crystal film ranges from 50 to 450.
6. The dual-layer dye liquid crystal film according to claim 1, wherein The haze of the double-layer dye liquid crystal film in a dark state is less than 5%, and the haze in a bright state is less than 2%.
7. The dual-layer dye liquid crystal film according to claim 1, wherein The thickness of the double-layer dye liquid crystal film ranges from 0.8 mm to 1.0 mm.
8. A liquid crystal light adjusting device, characterized by comprising: The double-layer dye liquid crystal film is arranged between the two transparent substrate layers.
9. The liquid crystal light modulating device of claim 8, wherein, The double-layer dye liquid crystal film and the two transparent substrate layers are adhered by an optical transparent adhesive.