A liquid crystal type electro-optic beam angle control device based on an L-shaped electrode strip

Abstract

The present invention discloses a liquid crystal type electrically controlled beam angle regulation device based on L-shaped electrode strips, which comprises a first substrate, a second substrate, a liquid crystal layer, an electrode assembly and a driving unit; the electrode assembly comprises regulation units arranged in a matrix; the regulation unit comprises a first driving electrode and a second driving electrode; the first driving electrode and the second driving electrode comprise N transparent electrode strips in an L shape and metal electrodes connected between the N transparent electrode strips; the i-th first driving electrode and the i-th second driving electrode correspond to the L-shaped transparent electrode strips of all independent dimming areas on the i-th matrix diagonal line and the (N-i)-th matrix diagonal line; the structures of the L-shaped transparent electrode strips on the same diagonal line are the same, and the structures of the L-shaped transparent electrode strips on adjacent diagonal lines are mirror images. The present invention can realize the reasonable arrangement of electrodes in the case of multi-pattern electrodes, effectively improve the electrode processing yield, and increase the light transmission effect of the regulation device.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid crystal diffusion sheets, and more particularly to a liquid crystal electro-optic beam angle control device based on an L-shaped electrode strip. Background Art

[0002] Liquid crystal materials have both birefringence and dielectric anisotropy, and are widely used in modern optical products. By utilizing these properties of liquid crystals, through electrode design, liquid crystal alignment layer design, etc., a regular refractive index change can be formed in the direction perpendicular to the substrate, which can be used to control the polarization direction of light, resulting in a variety of liquid crystal display devices on the market. Through electrode design, drive circuit waveform design, alignment design, etc., the liquid crystal can be electrically controlled to switch between an orderly arrangement and a disorderly arrangement. In the disorderly arrangement, liquid crystal domains with randomly varying refractive indices within a certain range are formed. When light passes through these liquid crystal domains, random refraction occurs. When the thickness of the liquid crystal layer is large enough (usually 10 μm or more), a uniform scattering effect is formed. Typical products include dynamic scattering liquid crystal cells, PDLC (polymer dispersed liquid crystal) liquid crystal cells, smectic A phase multistable liquid crystal cells, etc. By designing the alignment material, a regular arrangement of liquid crystals with a refractive index varying according to a sine law can be formed, and a liquid crystal polarization grating can be fabricated, which can be used to control the refraction angle of polarized light. The scattering formed by the disorderly arrangement of liquid crystals such as PDLC is caused by multiple random refractions of incident light, and the direction is uncontrollable. Moreover, some light is reflected back to the incident light side, resulting in a low overall transmittance of the product in the scattering state.

[0003] As Figure 1 shown, the liquid crystal cell includes an upper substrate 101, a lower substrate 102, an upper alignment layer 103, a lower alignment layer 104, liquid crystal 105, and drive electrodes 106. The liquid crystal 105 is sandwiched between the upper substrate 101 and the lower substrate 102. The upper substrate 101 is coated with the upper alignment layer 103, and the lower substrate 102 is coated with the lower alignment layer 105. Strip-shaped drive electrodes parallel to each other are etched on the lower substrate 102. By means of electrode design, alignment design, surface topography design, drive electric field design, etc., a regularly varying refractive index change can be formed in the direction parallel to the upper substrate 101 and the lower substrate 102 for the liquid crystal 105, and some very useful light control effects can also be achieved. By designing the electrode shape or the strength of the electric field, an arrangement in which the refractive index of the liquid crystal 105 increases or decreases from the center of the product to the periphery can be formed, resulting in the effect of a concave lens or a convex lens, and the focal length can also be electrically controlled. As Figure 1Convert the incident light 107 parallel to the substrate into the outgoing light 108 with a converging effect. The invention with the publication number CN103792740B discloses a tunable liquid crystal optical device, which is based on this principle. For the incident light perpendicular to the surface of the substrate and with the polarization direction parallel to the liquid crystal molecule arrangement direction, when passing through the liquid crystal cell, the optical paths on the left, middle, and right are different. The optical path in the middle is the largest (close to ne*d), and the optical paths directly above the electrodes on both sides are the smallest (close to no*d). This liquid crystal cell is equivalent to a convex lens. The width of the liquid crystal cell is very small (<50um), and the focal length of the lens is also very small. The minimum focal length is usually <0.1mm. Therefore, in actual use, the light-converging effect cannot be seen, and only the light-diverging effect can be seen. Replacing the liquid crystal with a negative liquid crystal has a similar effect. Therefore, the liquid crystal cells of an electrode pair form an optical effect similar to that of a cylindrical lens. Since only one layer of liquid crystal cell can correspond to the light of one polarization direction, in actual applications, through the stacked structure of the liquid crystal cell 201, the optical adhesive 202, the liquid crystal cell 203, and the PCB board 204 (as Figure 2 shown), the polarization dependence is eliminated, and the effective diffusion of parallel light is achieved. Sometimes, a 4-layer cell structure such as Figure 3 (the stacked structure of the liquid crystal cell 301, the liquid crystal cell 302, the liquid crystal cell 303, the liquid crystal cell 304, and the PCB board 305, and the optical adhesive 306 is filled between adjacent liquid crystal cells) is used because a larger diffusion angle and better diffusion uniformity can be achieved. In terms of the electrode structure design, as Figure 4a and Figure 4b shown, the electrode consists of strip-shaped electrode pairs, and a single-layer ITO electrode design is adopted. It is divided into four regions: upper left, lower left, upper right, and lower right. The electrode consists of a series of parallel ITO electrode pairs on the same layer of ITO. Finally, the electrodes of the same color are incorporated into the same group of electrode pairs and led out. Similar electrode design methods are adopted for both the upper and lower substrates. When forming the cell, the directions of the electrode pairs at the corresponding positions of the upper and lower substrates are perpendicular to each other. Two driving electrodes are led out from each of the upper and lower substrates. Therefore, there are a total of two pairs (4 pieces) of driving electrodes.

[0004] However, the diffusion effect of the liquid crystal diffuser with the foregoing structure design is not ideal because the electrode pairs are designed in 4 directions, and the light diffusion directions caused by the electrode pairs in each direction are perpendicular to the electrode pair directions. Therefore, the incident light is diffused in 8 directions (in a cross shape). At different positions of the cross shape, there are also some differences in the light color, resulting in chromatic dispersion. Figure 7 In (a) is a schematic diagram of the diffusion effect of the foregoing double-layer liquid crystal sheet structure when parallel light is incident. Although a 4-layer liquid crystal sheet structure is adopted, the diffusion will be more uniform and the chromatic dispersion will be more slight. However, first, the cost increases, and second, the diffusion uniformity is only better than that of the 2-layer liquid crystal sheet structure, and the cross shape cannot be significantly eliminated in actual applications.

[0005] Although theoretically increasing the types of pattern electrodes can optimize the aforementioned cross-shaped problem, different from the design where there are only 4 types of pattern electrodes on a diffuser sheet and each type of pattern electrode can lead out leads in four directions respectively, increasing the types of pattern electrodes will lead to difficulties in leading out leads and a decrease in the yield of the electrode etching process. The more types of pattern electrodes there are, the more prominent the aforementioned problems become. If there is more than one control unit on a diffuser sheet, or when the shape of the diffuser sheet does not allow the arrangement of several complete control units, how to design the corner electrodes to ensure the best scattering effect, these problems have not been studied by anyone yet. Summary of the Invention

[0006] Aiming at the deficiencies in the prior art, the present invention provides a liquid crystal type electro-optic beam angle control device based on L-shaped electrode strips, which can realize the reasonable arrangement of electrodes in the case of multiple pattern electrodes, effectively improve the yield of electrode processing, and increase the light transmission effect of the control device; on this basis, it can realize an arbitrary-shaped outgoing light spot while ensuring the uniformity of the light intensity of the outgoing light, reduce the outgoing loss and the dependence on the light intensity of the incident light, and at the same time expand the application occasions of the liquid crystal type diffuser sheet.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A liquid crystal type electro-optic beam angle control device based on L-shaped electrode strips, the control device includes a first substrate, a second substrate, a liquid crystal layer, an electrode assembly and a driving unit;

[0009] The first substrate and the second substrate are arranged opposite to each other to form a closed liquid crystal cell, and a liquid crystal material is filled in the liquid crystal cell to form a liquid crystal layer; an alignment layer is provided on the first substrate or the second substrate to control the liquid crystal material to be arranged in a preset orientation in the power-off state;

[0010] The first substrate and the second substrate are both etched with an electrode assembly; the electrode assembly includes one or more control units arranged in a matrix;

[0011] Each of the control units includes N first driving electrodes and N second driving electrodes; the first driving electrodes and the second driving electrodes are correspondingly combined to form N 2 independent dimming areas; two sets of mutually parallel pattern electrodes are provided in each independent dimming area, and the two sets of pattern electrodes are respectively connected to the first driving electrode and the second driving electrode corresponding to the independent dimming area; the first driving electrodes and the second driving electrodes on the first substrate and the second substrate are independently led out of the liquid crystal cell and connected to the driving unit to provide a predetermined driving signal for the two sets of pattern electrodes in each independent dimming area, so that the liquid crystal material located thereon generates different spatial changes in orientation under the action of an electric field; N is a positive integer greater than 1;

[0012] The pattern electrodes of the control units at the same position on the first substrate and the second substrate are perpendicular to each other, and within the range of the same control unit, the pattern electrodes on a single row and a single column are different from each other;

[0013] The first driving electrode and the second driving electrode include N L-shaped transparent electrode strips and a metal electrode connected between the N transparent electrode strips, and the width of the metal electrode is much smaller than the width of the transparent electrode strips;

[0014] Regarding the N 2 independent dimming areas in each unit control area as an N*N matrix, the i-th first driving electrode and the i-th second driving electrode correspond to the L-shaped transparent electrode strips of all the independent dimming areas on the i-th matrix diagonal line and the (N - i)-th matrix diagonal line, where i = 1, 2, …, N; among them, when N is an even number and i = N / 2, or when N is an odd number and i = (N + 1) / 2, the i-th first driving electrode and the i-th second driving electrode correspond to the L-shaped transparent electrode strips of all the independent dimming areas on the matrix diagonal line;

[0015] The structures of the L-shaped transparent electrode strips on the same diagonal line are the same, and the structures of the L-shaped transparent electrode strips on adjacent diagonal lines are mirror images.

[0016] Furthermore, each group of the pattern electrodes includes several electrode strips that are parallel to each other and form an angle with the driving electrode; the value range of the angle is from 0° to 360°.

[0017] Furthermore, the widths and the spacings between the electrode strips of the same type of pattern electrodes in different control units are different.

[0018] Furthermore, the inclination angles of the electrode strips of the pattern electrodes are 0 + α degrees, 1*180 / N + α degrees, 2*180 / N + α degrees, 3*180 / N + α degrees, …, (N - 1)*180 / N + α degrees; α is greater than or equal to 0.

[0019] Furthermore, the spacing range of the electrode strips of the pattern electrodes is 10um - 100um.

[0020] Furthermore, the driving unit includes a diffusion shape control module; the diffusion shape control module adjusts the outgoing light spot parameters of each independent dimming area by adjusting the voltage applied to the pattern electrodes of each independent dimming area according to the ideal profile of the diffused light, so that the profile of the finally outgoing light tends to be consistent with the ideal profile of the diffused light; specifically, it includes the following steps:

[0021] Analyze and obtain the diffusion direction vector of each independent dimming area

[0022] Combined with the liquid crystal layer and pattern electrode parameters, obtain the relationship function between the voltage of each independent dimming area and the beam angle in the corresponding diffusion direction

[0023] Analyze the ideal profile of the diffused light, and calculate the theoretical beam angles on all diffusion direction vectors Calculate the corresponding driving voltage

[0024] Furthermore, when parallel light is incident, the focal length f and the maximum diffusion angle θ of the outgoing light are respectively:

[0025]

[0026] θ = 2arctan(L / 2f);

[0027] In the formula, L is the distance between adjacent electrode strips in the independent dimming area; D is the thickness of the liquid crystal layer; Δn = ne - no

[0028] The present invention also mentions an electrically controlled beam regulation system, which is characterized in that the electrically controlled beam regulation system includes a plurality of stacked liquid crystal type electrically controlled beam angle regulation devices based on L-shaped electrode strips as described above; the diffusion angles of the independent dimming areas of adjacent liquid crystal type electrically controlled beam angle regulation devices differ by 90 degrees, and a polarization control sheet is filled between adjacent liquid crystal type electrically controlled beam angle regulation devices

[0029] Furthermore, according to the ideal profile of the diffused light, the electrically controlled beam regulation system adjusts the outgoing spot parameters of each independent dimming area by adjusting the voltage applied to the pattern electrodes of each independent dimming area of each liquid crystal type electrically controlled beam angle regulation device, so that the profile of the final outgoing light tends to be consistent with the ideal profile of the diffused light. Specifically, it includes the following steps:

[0030] S1. For any layer of electrically controlled beam angle regulation device, analyze the diffusion direction vectors of each independent dimming area corresponding to it Define one layer of the electrically controlled beam angle regulation device as the reference layer, and resolve the diffusion directions of other electrically controlled beam angle regulation devices to be the same as the diffusion direction of the reference layer, to obtain the reference diffusion direction vector group of the independent dimming areas corresponding to the electrically controlled beam regulation system

[0031] S2. Combined with the liquid crystal layer and pattern electrode parameters, obtain the relationship function between the voltage, light intensity and the beam angle in the corresponding diffusion direction of each independent dimming area of any layer of electrically controlled beam angle regulation device G j,k () is the voltage V of the jth ‘ kind of independent dimming area of the kth layer of electrically controlled beam angle regulation device j‘,kThe relationship function with the reference diffusion direction of the beam angle ; F j‘,k is the voltage V ‘ of the j j‘,k th independent dimming area of the kth layer of the electro-controlled beam angle adjustment device and the light intensity of the reference diffusion direction

[0032] S3. Analyze the ideal profile of the diffused light, and calculate the theoretical beam angle on all reference diffusion direction vectors The voltage value V on the pattern electrode of the jth independent dimming area of the kth layer of the electro-controlled beam angle adjustment device is calculated by using the following formula j,k :

[0033]

[0034] In the formula, j * = 1, 2,..., N, j * ≠ j; E * is the minimum allowable light intensity threshold, which is related to the light intensity of the incident light and the application requirements

[0035] Furthermore, in step S1, the process of resolving the diffusion direction of other electro-controlled beam angle adjustment devices into the same diffusion direction as that of the reference layer includes the following steps

[0036] S11. Select any electro-controlled beam angle adjustment device other than the reference layer, and determine whether it has a diffusion direction different from that of the reference layer. If not, go to step S13; otherwise, go to step S12

[0037] S12. For each different diffusion direction, screen out two reference diffusion directions of the adjacent reference layer, and decompose this diffusion direction into sub-vectors of the two screened reference diffusion directions according to the angular relationship

[0038] S13. Return to step S11, and re-select the electro-controlled beam angle adjustment device until all electro-controlled beam angle adjustment devices are processed

[0039] The beneficial effects of the present invention are

[0040] First, the liquid crystal type electro-controlled beam angle adjustment device based on the L-shaped electrode strip of the present invention can realize the reasonable arrangement of electrodes in the case of multiple pattern electrodes, effectively improve the electrode processing yield, and increase the light transmission effect of the adjustment device; on this basis, it can realize an arbitrary-shaped outgoing light spot while ensuring the uniformity of the light intensity of the outgoing light, reduce the outgoing loss and the dependence on the light intensity of the incident light, and at the same time expand the application occasions of the liquid crystal type diffuser

[0041] Second, by adjusting the driving voltage applied to the multiple independent regulation regions included in the regulation unit, the outgoing light spot parameters of each independent regulation region can be controlled, enabling fine control of the diffusion of each light spot and achieving control of more complex diffusion patterns (such as ellipse, square, rectangle, etc.).

[0042] Third, the liquid crystal type electronically controlled light beam angle regulation device based on the L-shaped electrode strip of the present invention reduces the size in each diffusion direction, and the directions of diffusion inside the light spot are more disordered, which is more conducive to diffusion uniformity.

[0043] Fourth, the electronically controlled light beam regulation system of the present invention adopts the stacking method of multiple diffusion sheets (liquid crystal type electronically controlled light beam angle regulation devices), further broadening the diffusion area and making the diffused light more uniform.

[0044] Fifth, the electronically controlled light beam regulation system of the present invention controls each independent regulation region of the multiple diffusion sheets separately. On the basis of realizing special-shaped light spots, the light intensity distribution of the special-shaped light spots is optimized, improving the uniformity of the light intensity distribution. Description of the Drawings

[0045] Figure 1 It is a schematic diagram of the diffusion principle of liquid crystal materials.

[0046] Figure 2 It is a schematic diagram of the two-layer stacking method of the existing diffusion sheet.

[0047] Figure 3 It is a schematic diagram of the four-layer stacking method of the existing diffusion sheet.

[0048] Figure 4a and Figure 4b are respectively schematic diagrams of the electrode pattern structures of the upper substrate and the lower substrate of the existing diffusion sheet.

[0049] Figure 5a It is a schematic diagram of the structure of the liquid crystal type electronically controlled light beam angle regulation device based on the L-shaped electrode strip according to an embodiment of the present invention.

[0050] Figure 5b It is a schematic diagram of one of the pattern electrodes according to an embodiment of the present invention.

[0051] Figure 6 It is a schematic diagram of the structure of the electronically controlled light beam regulation system of the present invention.

[0052] Figure 7Schematic diagram of the comparison result of the diffusion effect between the liquid crystal type electro - controlled beam angle regulation device of the embodiment of the present invention and the diffusion sheet of the prior art; (a) is the schematic diagram of the diffusion effect after stacking 2 layers of the diffusion sheet of the prior art, (b) is the schematic diagram of the diffusion effect after stacking 2 layers of the liquid crystal type electro - controlled beam angle regulation device of the embodiment of the present invention, and (c) is the schematic diagram of the diffusion effect after stacking 4 layers of the liquid crystal type electro - controlled beam angle regulation device of the embodiment of the present invention.

[0053] Figure 8 Schematic diagram of the relationship between the beam angle and voltage in the independent regulation area of the embodiment of the present invention.

[0054] Figure 9 Schematic diagram of the electrode structure in the unit regulation area of the embodiment of the present invention. Detailed implementation manners

[0055] Now, the present invention will be further described in detail with reference to the accompanying drawings.

[0056] It should be noted that the terms such as "upper", "lower", "left", "right", "front", "rear", etc. cited in the invention are only for the convenience of narration and are not used to limit the scope of implementation of the present invention. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the scope of implementation of the present invention.

[0057] See Figure 5a , this embodiment discloses a liquid crystal type electro - controlled beam angle regulation device with independent partitions. The regulation device includes a first substrate 501, a second substrate 504, a liquid crystal layer 503, an electrode assembly 502, and a driving unit 505.

[0058] The first substrate 501 and the second substrate 504 are arranged opposite to each other to form a closed liquid crystal cell, and a liquid crystal material is filled in the liquid crystal cell to form a liquid crystal layer 503; an alignment layer (not marked) is provided on the first substrate 501 or the second substrate 504 to control the liquid crystal material to be arranged in a preset orientation in the power - off state.

[0059] The electrode assemblies 502 are etched on both the first substrate 501 and the second substrate 504; the electrode assembly 502 includes one or more regulation units arranged in a matrix.

[0060] See Figure 9 , each of the regulation units includes N first driving electrodes and N second driving electrodes; the first driving electrodes and the second driving electrodes are correspondingly combined to form N 2 independent dimming areas; two sets of mutually parallel pattern electrodes are arranged in each independent dimming area, and the two sets of pattern electrodes are respectively connected to the first driving electrode and the second driving electrode corresponding to the independent dimming area Figure 5bIt is a schematic diagram of one of the pattern electrodes in this embodiment, where N = 8. The first driving electrodes and the second driving electrodes of the first substrate and the second substrate are independently led out of the liquid crystal cell and connected to the driving unit, which is used to provide two sets of pattern electrodes in each independent dimming area with a predetermined driving signal, so that the liquid crystal material located thereon generates a spatial change in different orientations under the action of an electric field; the N is a positive integer greater than 1. As Figure 9 shown, from left to right, adjacent first driving electrodes and second driving electrodes form a driving combination, with a total of eight combinations from 1 to 8, and each driving combination controls 8 independent dimming areas respectively; it should be noted that different from the conventional liquid crystal electrode design, the 8 independent dimming areas controlled by each driving combination are not on the same vertical or horizontal line.

[0061] The pattern electrodes of the regulation units at the same position on the first substrate and the second substrate are perpendicular to each other, and within the range of the same regulation unit, the pattern electrodes on a single row and a single column are different from each other.

[0062] The driving unit 505 includes a diffusion shape control module; the diffusion shape control module adjusts the outgoing light spot parameters of each independent dimming area by adjusting the voltage applied to the pattern electrodes of each independent dimming area according to the ideal profile of the diffused light, so that the profile of the finally outgoing light tends to be consistent with the ideal profile of the diffused light.

[0063] In practical applications, the larger the number of N, the more diffusion directions, the better the diffusion effect, and correspondingly, the more complex the driving algorithm. Preferably, N≥4, and correspondingly, the inclination angles of the electrode strips of the pattern electrodes are 0 + α degrees, 1 * 180 / N + α degrees, 2 * 180 / N + α degrees, 3 * 180 / N + α degrees,..., (N - 1) * 180 / N + α degrees; α is greater than or equal to 0. For the same liquid crystal type electro-optic beam angle regulation device, as long as the value of α is fixed, the diffusion results are actually equivalent. When liquid crystal type electro-optic beam angle regulation devices are stacked, the values of α of different diffusion sheets are different, and there will be differences in the diffusion effects. As Figure 5b shown, in this example, the value of N is 8. Each group of the pattern electrodes includes a plurality of electrode strips that are parallel to each other and form an angle with the driving electrodes; the value range of the angle is from 0° to 360°. In this example, the inclination angles of the electrode strips of the pattern electrodes are 0 degrees, 22.5 degrees, 45 degrees, 67.5 degrees, 90 degrees, 112.5 degrees, 135 degrees, and 157.5 degrees.

[0064] The size of a single regulation unit composed of the N * N dimming areas is smaller than the size of the inscribed square of the incident circular light spot, so that the incident light spot can cover enough independent dimming areas.

[0065] As Figure 9As shown, the first driving electrode and the second driving electrode include N L-shaped transparent electrode strips and metal electrodes connected between the N transparent electrode strips. The width of the metal electrode is much smaller than the width of the transparent electrode strip;

[0066] Regarding the N 2 independent dimming areas in each unit regulation area as an N*N matrix, the i-th first driving electrode and the i-th second driving electrode correspond to the L-shaped transparent electrode strips of all independent dimming areas on the i-th matrix diagonal and the (N - i)-th matrix diagonal, where i = 1, 2, …, N; among them, when N is even and i = N / 2, or when N is odd and i = (N + 1) / 2, the i-th first driving electrode and the i-th second driving electrode correspond to the L-shaped transparent electrode strips of all independent dimming areas on the matrix diagonal;

[0067] The structures of the L-shaped transparent electrode strips on the same diagonal are the same, and the structures of the L-shaped transparent electrode strips on adjacent diagonals are mirror images of each other.

[0068] The advantages of this electrode structure design are: First, the value of N can be arbitrarily set according to actual needs; Second, the loads of each driving electrode are not much different, which is beneficial to setting the driving voltage; Third, the light transmittance of the diffusion area is very high, which helps to improve the diffusion effect.

[0069] Preferably, differentiating the widths of the electrode strips and the spacings between the electrode strips of the same type of pattern electrodes for different regulation units helps to eliminate chromatic dispersion.

[0070] In this embodiment, the size of the independent dimming area is less than 5mm * 5mm, the size of the electrode strip is usually at the micron level (depending on the etching accuracy), the spacing range of the electrode strips of the pattern electrode is 10um - 100um, and the minimum focal length can reach within 50um. Taking Figure 5b the pattern electrode in it as an example, the size of each independent dimming area is 2mm or 0.5mm. Combining 8 electrode pair directions, the diffusion effects after superimposing the double-layer diffusion sheet and the four-layer diffusion sheet under the same light source are as shown in Figure 7 (b) and (c). Compared with Figure 7 the diffusion effect of the diffusion sheet of the prior art in (a), the diffusion sheet of this embodiment can achieve the diffusion effect in 8 pairs (16 directions), and the final spot uniformity is undoubtedly better. Specifically, there are no obvious stripes after diffusion of the double-layer diffusion sheet, and the chromatic dispersion phenomenon is also significantly reduced. Except for a slight bright spot in the middle position, the overall diffusion of the four-layer diffusion sheet is very uniform, and there is no chromatic dispersion phenomenon, and the effect is relatively ideal.

[0071] Figure 6It is a schematic structural diagram of one of the electronically controlled beam angle regulation systems. The electronically controlled beam angle regulation system includes an X-direction diffuser 601, a Y-direction diffuser 602, an X-direction diffuser 603, and a Y-direction diffuser 604 stacked in sequence. A liquid crystal polarization control sheet 605 is provided between adjacent diffusers. The diffusion effects after superimposing the double-layer diffuser and the four-layer diffuser under the same light source are as shown in Figure 7 (b) and (c) of Figure 7 . Compared with the diffusion effect of the diffuser in the prior art shown in (a) of Figure 7 , the diffuser in this embodiment can achieve the diffusion effect in 8 directions (16 in total). Undoubtedly, the final spot uniformity is better. Specifically, there are no obvious stripes after the double-layer diffuser diffuses, and the dispersion phenomenon is also significantly reduced. Except for a slight bright spot in the middle position, the overall diffusion of the four-layer diffuser is very uniform, and there is no dispersion phenomenon either. The effect is relatively ideal.

[0072] Refer to Figure 7 . The shape of the diffuser used is circular. When the driving voltages of each pattern electrode are the same, the emitted light spot is also circular. Assuming that the target irradiation area is a whole wall, the corner area cannot be irradiated under the current driving voltage. The light spot ranges after increasing the driving voltage are as shown in Figure 7 (b) and (c) of Figure 7 . Although the entire target irradiation area is covered, the actual irradiation area has actually extended to other wall areas, and the light energy utilization efficiency has not reached the best. For this reason, this embodiment proposes an adaptive control method for the shape of the emitted light spot.

[0073] Specifically, the process in which the diffusion shape control module adjusts the emitted light spot parameters of each independent dimming area by adjusting the voltage applied to the pattern electrode of each independent dimming area according to the ideal contour of the diffused light, so that the contour of the finally emitted light tends to be consistent with the ideal contour of the diffused light includes the following steps:

[0074] The process in which the diffusion shape control module adjusts the emitted light spot parameters of each independent dimming area by adjusting the voltage applied to the pattern electrode of each independent dimming area according to the ideal contour of the diffused light, so that the contour of the finally emitted light tends to be consistent with the ideal contour of the diffused light includes the following steps:

[0075] Analyze and obtain the diffusion direction vector of each independent dimming area

[0076] Combined with the liquid crystal layer and pattern electrode parameters, obtain the relationship function between the voltage of each independent dimming area and the beam angle in the corresponding diffusion direction

[0077] Analyze the ideal contour of the diffused light, and calculate the theoretical beam angles on all diffusion direction vectors Calculate the corresponding driving voltage

[0078] In this embodiment, in order to simplify the control process, a diffuser sheet generally only adopts one type of regulation unit, and the regulation units are distributed in a matrix form and controlled uniformly. Therefore, as Figure 5a shown, the diffuser sheet is currently only used to achieve symmetric non-standard light spots, such as ellipses, squares, rectangles, etc. If more diverse asymmetric structures need to be achieved, regulation units with a variety of different diffusion direction combinations need to be set on the diffuser sheet, and then each regulation unit is controlled separately. This embodiment only takes the diffuser sheet with parallel light incident and only one type of regulation unit as an example for illustration.

[0079] When parallel light is incident, the focal length f and the maximum diffusion angle θ of the outgoing light of each electrode pair are respectively:

[0080]

[0081] θ = 2arctan(L / 2f);

[0082] In the formula, L is the distance between adjacent electrode strips in the independent dimming area; D is the thickness of the liquid crystal layer.

[0083] In the case of parallel light incidence, with different voltages between the electrodes, the diffusion angle of a single independent dimming area can be adjusted between 0 and θ. Figure 8 is the measured beam angle situation at different voltages. For a certain test model sample, when the incident light divergence angle is 10.5 degrees, the range of the beam angle of the outgoing light is 10.5 degrees to 71.4 degrees. Taking Figure 5b the 8 pattern electrodes as an example, there are a total of 8 pairs of diffusion directions. If the driving voltages of each independent regulation area are the same, the beam angles of the 16 diffusion directions are also the same, and the shape of the outgoing light spot is nearly the same as the shape of the diffuser sheet. If the driving voltages of different independent regulation areas are different, then the beam angles in the 8 pairs of diffusion directions will also be different, and finally the presented outgoing light spots will be of different shapes. For example, when the diffuser sheet is circular, the driving voltage of the independent regulation area with the diffusion direction along the major axis is the largest, and the driving voltage of the independent regulation area with the diffusion direction along the minor axis is the smallest, that is, the final effect of an elliptical outgoing light spot can be achieved.

[0084] The larger the beam angle, the smaller the light intensity in the diffusion direction. In some examples, when the difference between the major axis and the minor axis of the outgoing light spot is too large, the problem of uneven light intensity distribution is likely to occur. For this reason, this embodiment also mentions an electronically controlled beam regulation system, which includes a plurality of stacked liquid crystal type electronically controlled beam angle regulation devices with independent partitions as described above; the diffusion angles of the independent dimming areas of adjacent liquid crystal type electronically controlled beam angle regulation devices differ by 90 degrees, and a polarization control film is filled between adjacent liquid crystal type electronically controlled beam angle regulation devices. Devices such as liquid crystal wave plates or TN type liquid crystal plates may not contain polarizing films.

[0085] According to the ideal profile of the diffused light, the electronically controlled beam regulation system adjusts the outgoing light spot parameters of each independent dimming area by adjusting the voltage applied to the pattern electrodes of each independent dimming area of each layer of the liquid crystal type electronically controlled beam angle regulation device, so that the profile of the finally outgoing light tends to be consistent with the ideal profile of the diffused light. The specific steps are as follows:

[0086] S1. For any layer of the electronically controlled beam angle regulation device, analyze the diffusion direction vectors of each corresponding independent dimming area Define one layer of the electronically controlled beam angle regulation device as the reference layer, and resolve the diffusion directions of other electronically controlled beam angle regulation devices to be the same as the diffusion direction of the reference layer, so as to obtain the reference diffusion direction vector group of the independent dimming areas corresponding to the electronically controlled beam regulation system

[0087] Specifically, in step S1, the process of resolving the diffusion directions of other electronically controlled beam angle regulation devices to be the same as the diffusion direction of the reference layer includes the following steps:

[0088] S11. Select any electronically controlled beam angle regulation device other than the reference layer, and determine whether it has a diffusion direction different from that of the reference layer. If not, go to step S13; otherwise, go to step S12. S12. For each different diffusion direction, screen out two reference diffusion directions of the adjacent reference layer, and decompose this diffusion direction into sub-vectors of the two screened reference diffusion directions according to the angular relationship. S13. Return to step S11, and re-select the electronically controlled beam angle regulation device until all electronically controlled beam angle regulation devices are processed.

[0089] For example, when N is 2, each layer of diffuser corresponds to 4 diffusion directions, and the angle between adjacent diffusion directions is 90 degrees. If the electrode pair directions of adjacent diffusers at the same position are perpendicular to each other, the diffusion directions of each layer of diffuser are still consistent in the end. When N is 3, each layer of diffuser corresponds to 6 diffusion directions, and the angle between adjacent diffusion directions is 60 degrees. If the electrode pair directions of adjacent diffusers at the same position are perpendicular to each other, the diffusion directions of each layer of diffuser are no longer consistent. At this time, one of the diffusers can be selected as the reference diffuser to obtain the reference diffusion direction, and then the diffusion directions of other diffusers can be decomposed to the reference diffusion direction by means of angle analysis. The purpose of this step is to effectively control the shape and light intensity uniformity of the outgoing light spot.

[0090] S2. Combine the liquid crystal layer and the pattern electrode parameters to obtain the relationship function of the voltage, light intensity, and the beam angle of the corresponding diffusion direction for each independent dimming area of any layer of the electro-control beam angle adjustment device. G j,k () is the voltage V of the jth ‘ independent dimming area of the kth layer of the electro-control beam angle adjustment device j‘,k and the beam angle of the reference diffusion direction relationship function; F j‘,k is the voltage V of the jth ‘ independent dimming area of the kth layer of the electro-control beam angle adjustment device j‘,k and the light intensity of the reference diffusion direction relationship function.

[0091] Suppose two layers of diffusers are stacked. After parallel light is incident on the first layer of diffuser, it diffuses in 16 diffusion directions. The scattered light in these 16 diffusion directions and the part of the parallel light that is not scattered will simultaneously be incident on the second layer of diffuser for re-diffusion. For the part of the parallel light that is not scattered, it will diffuse again in the 16 diffusion directions corresponding to the second layer of diffuser. In theory, the scattered light in the 16 diffusion directions of the first layer of diffuser will also be re-scattered by the second layer of diffuser. To simplify the calculation process, this embodiment only calculates the scattered light intensity and beam angle of the part of the parallel light that is not scattered. After testing, although the beam angle and light intensity of the scattered light of the previous layer of diffuser change slightly when passing through the next layer, compared with the superimposed scattering effect of the next layer of diffuser on the parallel light, its influence on the shape and light intensity distribution of the final outgoing light spot is relatively small.

[0092] S3. Analyze the ideal profile of the diffused light and calculate the theoretical beam angles on all reference diffusion direction vectors. The voltage value V on the pattern electrode of the jth independent dimming area of the kth layer of the electro-control beam angle adjustment device is calculated using the following formula: j,k :

[0093]

[0094] where j * = 1, 2, …, N, j * ≠ j; E * is the minimum allowable light intensity threshold, which is related to the light intensity of the incident light and the application requirements.

[0095] The electro - controlled beam regulation system of this embodiment can finally achieve the emission of a special - shaped light spot, and on the premise that the light intensity of the special - shaped light spot meets the lowest standard, further improves the uniformity of the light intensity distribution of the special - shaped light spot.

[0096] The above is only the preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above - mentioned embodiments. All technical solutions falling within the idea of the present invention belong to the protection scope of the present invention. It should be pointed out that for those of ordinary skill in the art, several improvements and refinements made without departing from the principle of the present invention should be regarded as within the protection scope of the present invention.

Claims

1. A liquid crystal type electro-optic beam angle regulation device based on an L-shaped electrode strip, characterized in that, The control device includes a first substrate, a second substrate, a liquid crystal layer, an electrode assembly, and a driving unit; The first substrate and the second substrate are disposed opposite to each other to form a closed liquid crystal cell, and a liquid crystal material is filled in the liquid crystal cell to form a liquid crystal layer; an alignment layer is provided on the first substrate or the second substrate to control the liquid crystal material to be arranged in a preset orientation in the power-off state; Electrode assemblies are etched on both the first substrate and the second substrate; the electrode assembly includes one or more control units arranged in a matrix; Each of the control units includes N first driving electrodes and N second driving electrodes; the first driving electrodes and the second driving electrodes are correspondingly combined to form N 2 independent dimming areas; two sets of mutually parallel pattern electrodes are arranged in each independent dimming area, and the two sets of pattern electrodes are respectively connected to the first driving electrode and the second driving electrode corresponding to the independent dimming area; the first driving electrodes and the second driving electrodes of the first substrate and the second substrate are independently led out of the liquid crystal cell and connected to the driving unit for providing two sets of pattern electrodes in each independent dimming area with a predetermined driving signal, so that the liquid crystal material located thereon generates a spatial change of different orientations under the action of an electric field; the N is a positive integer greater than 1; The pattern electrodes of the control units at the same position on the first substrate and the second substrate are perpendicular to each other, and within the range of the same control unit, the pattern electrodes on a single row and a single column are different from each other; The first driving electrode and the second driving electrode include N L-shaped transparent electrode strips and a metal electrode connected between the N transparent electrode strips, and the width of the metal electrode is much smaller than the width of the transparent electrode strip; Regarding the N independent dimming areas in each unit control area as an N*N matrix, the i-th first driving electrode and the i-th second driving electrode correspond to the L-shaped transparent electrode strips of all the independent dimming areas on the i-th matrix diagonal line and the (N-i)-th matrix diagonal line, where i = 1, 2,..., N; among them, when N is an even number and i = N / 2, or when N is an odd number and i = (N+1) / 2, the i-th first driving electrode and the i-th second driving electrode correspond to the L-shaped transparent electrode strips of all the independent dimming areas on the matrix diagonal line; 2 ​ The structures of the L-shaped transparent electrode strips on the same diagonal line are the same, and the structures of the L-shaped transparent electrode strips on adjacent diagonal lines are mirror images.

2. The liquid crystal type electrically controlled beam angle adjustment device based on the L-shaped electrode strip according to claim 1, characterized in that Each group of the pattern electrodes includes a plurality of electrode strips that are parallel to each other and form an angle with the driving electrode; the value range of the angle is from 0° to 360°.

3. The liquid crystal type electro-optic beam angle regulation device based on the L-shaped electrode strip according to claim 2, characterized in that, The widths of the electrode strips and the distances between the electrode strips of the same type of pattern electrodes in different control units are different.

4. The liquid crystal type electro-optic beam angle regulation device based on the L-shaped electrode strip according to claim 2, wherein The inclination angles of the electrode strips of the pattern electrodes are 0 + α degrees, 1 * 180 / N + α degrees, 2 * 180 / N + α degrees, 3 * 180 / N + α degrees,..., (N - 1) * 180 / N + α degrees; α is greater than or equal to 0.

5. The liquid crystal type electro-control beam angle regulation device based on the L-shaped electrode strip according to claim 1, characterized in that The distance range between the electrode strips of the pattern electrodes is 10um - 100um.

6. The liquid crystal type electro-optic beam angle regulation device based on an L-shaped electrode strip according to claim 1, wherein, The driving unit includes a diffusion shape control module; the diffusion shape control module adjusts the outgoing light spot parameters of each independent dimming area by adjusting the voltage applied to the pattern electrodes in each independent dimming area according to the ideal profile of the diffused light, so that the profile of the finally outgoing light tends to be consistent with the ideal profile of the diffused light; specifically includes the following steps: Analyze to obtain the diffusion direction vectors of each independent dimming area Combined with the liquid crystal layer and the pattern electrode parameters, obtain the relationship function between the voltage of each independent dimming area and the beam angle in the corresponding diffusion direction Analyze the ideal profile of the diffused light and calculate the theoretical beam angles on all diffused direction vectors Calculate the corresponding driving voltage 7. The liquid crystal type electro-optic beam angle control device based on the L-shaped electrode strip according to claim 2, wherein When parallel light is incident, the focal length f and the maximum diffusion angle θ of the outgoing light are respectively: θ = 2arctan(L / 2f); In the formula, L is the distance between adjacent electrode strips of the independent dimming area; D is the thickness of the liquid crystal layer; Δn = ne - no, where ne and no respectively represent the refractive indices of the liquid crystal along the optical axis direction and perpendicular to the optical axis direction.

8. An electronically controlled light beam modulation system, characterized in that, The electro-optic beam control system includes a plurality of stacked liquid crystal type electro-optic beam angle control devices as described in any one of claims 1-7 based on L-shaped electrode strips; the diffusion angles of the independent dimming areas of adjacent liquid crystal type electro-optic beam angle control devices differ by 90 degrees, and a polarization control film is filled between adjacent liquid crystal type electro-optic beam angle control devices.

9. The electro-optical beam control system according to claim 8, wherein The electro-optic beam control system adjusts the outgoing light spot parameters of each independent dimming area by adjusting the voltage applied to the pattern electrodes in each independent dimming area of each layer of the liquid crystal type electro-optic beam angle control device according to the ideal profile of the diffused light, so that the profile of the finally outgoing light tends to be consistent with the ideal profile of the diffused light, specifically includes the following steps: S1. For any layer of the electro-control beam angle adjustment device, analyze the diffusion direction vectors of each independent dimming area corresponding thereto Define one layer of the electro-control beam angle adjustment device as the reference layer, and resolve the diffusion directions of other electro-control beam angle adjustment devices to be consistent with the diffusion direction of the reference layer, so as to obtain the reference diffusion direction vector group of the independent dimming area corresponding to the electro-control beam adjustment system S2. Combine the liquid crystal layer and the pattern electrode parameters to obtain the relationship functions of the voltage, light intensity, and the beam angle in the corresponding diffusion direction for each independent dimming region of any one of the electro-optic beam angle modulation devices. G j,k () is the voltage V of the j-th ‘ independent dimming region of the k-th electro-optic beam angle modulation device j‘,k and the beam angle in the reference diffusion direction ; F j‘,k is the voltage V of the j-th ‘ independent dimming region of the k-th electro-optic beam angle modulation device j‘,k and the light intensity in the reference diffusion direction ; S3. Analyze the ideal profile of the diffused light and calculate the theoretical beam angles on all reference diffusion direction vectors. The voltage value V on the pattern electrode of the j-th independent dimming area of the k-th layer of the electro-optic beam angle control device is calculated using the following formula. j,k : where j * = 1, 2, …, N, j * ≠ j; E * is the minimum allowable light intensity threshold, which is related to the light intensity of the incident light and the application requirements.

10. The electro-optical beam control system according to claim 9, characterized in that, In step S1, the process of resolving the diffusion direction of other electro-control beam angle adjustment devices to be the same as that of the reference layer includes the following steps: S11. Select any electro-control beam angle adjustment device other than the reference layer, and determine whether it has a diffusion direction different from that of the reference layer. If not, proceed to step S13; otherwise, proceed to step S12; S12. For each different diffusion direction, screen out two reference diffusion directions of the adjacent reference layer, and decompose this diffusion direction into sub-vectors of the two screened reference diffusion directions according to the angular relationship; S13. Return to step S11, and re-select the electro-control beam angle adjustment device until all electro-control beam angle adjustment devices are processed.

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