Laser beam collimation and shaping device, method and system

Abstract

The invention relates to the technical field of optics, and provides a laser light beam collimating and shaping device, method and system. The device comprises an upper-layer liquid crystal box, a lower-layer liquid crystal box and a third substrate shared between the upper-layer liquid crystal box and the lower-layer liquid crystal box; an upper substrate of the upper-layer liquid crystal box and a lower substrate of the lower-layer liquid crystal box are respectively provided with a plurality of first strip-shaped electrodes which are transversely arranged and a plurality of second strip-shaped electrodes which are longitudinally arranged, and are respectively used for applying adjustable voltages which are obtained according to divergence angles of a fast axis and a slow axis of an incident light beam and are distributed in a transverse upper opening parabola and a longitudinal upper opening parabola; driving liquid crystal molecules in the upper-layer and lower-layer liquid crystal boxes to deflect transversely and longitudinally to form refractive indexes of transverse and longitudinal lower-opening parabola distribution, collimating the fast and slow axis divergence angles of an incident light beam in sequence, and finishing the shaping of the incident light beam; and the middle electrode layer on the third substrate is grounded and forms electric field distribution with the first strip-shaped electrode and the second strip-shaped electrode respectively. According to the scheme disclosed by the invention, light beams with different divergence angles can be collimated and shaped without replacing a lens group or adjusting the distance between lenses.

Description

Technical Field

[0001] The present invention relates to the field of optical technologies, and in particular, to a laser beam collimation and shaping device, method, and system. Background Art

[0002] The aspect ratio of the active region of an edge-emitting semiconductor laser (width much larger than thickness) results in significant differences in the divergence angles parallel to the junction plane (transverse) and perpendicular to the junction plane (longitudinal) (usually the transverse divergence angle is 10 - 30°, and the longitudinal divergence angle is 30 - 60°), and the far-field spot is elliptical, with poor beam quality (M 2 factor). In the scenario of free-space optical communication, it is necessary to shape the elliptical beam into a circular beam without divergence angle to improve the efficiency of the transmitting antenna. In the scenario of fiber-optic communication, it is necessary to optimize the beam directivity and the uniformity of the spot energy density (for example, shaping a Gaussian beam into a flat-top beam) to improve the fiber coupling efficiency (the typical requirement is a coupling efficiency > 90%).

[0003] In the existing methods for laser beam collimation and shaping, it is generally achieved through the cylindrical lens group technology. For example, in the existing publicly disclosed patent CN221406205U, cylindrical lenses with fixed focal lengths are used to collimate in the transverse (fast axis) and longitudinal (slow axis) directions respectively, but the focal length cannot be dynamically adjusted to adapt to incident beams with different divergence angles. If different lasers need to be adapted, it is necessary to physically replace the lens group or mechanically adjust the lens spacing, and the shaping ability for complex elliptical light is limited.

[0004] Based on this, there is an urgent need for improvement in the existing technology. Summary of the Invention

[0005] Aiming at the problem in the existing technology that the fixed optical parameters cannot be dynamically adjusted to adapt to incident beams with different divergence angles, the present invention provides a laser beam collimation and shaping device, method, and system.

[0006] Based on the above purpose, one aspect of the embodiments of the present invention provides a laser beam collimation and shaping device, including: An upper liquid crystal cell, the upper liquid crystal cell includes an upper substrate, and the upper substrate is provided with a plurality of first strip electrodes arranged transversely, used to apply an adjustable voltage with a horizontally upward-opening parabola distribution through it to drive the liquid crystal molecules in the upper liquid crystal cell to deflect transversely to form a refractive index with a horizontally downward-opening parabola distribution, so as to collimate the fast-axis divergence angle of the incident beam, and the adjustable voltage with the horizontally upward-opening parabola distribution is calculated based on the fast-axis divergence angle; Lower liquid crystal cell, the lower liquid crystal cell includes a lower substrate, the lower substrate is provided with a plurality of second strip electrodes arranged longitudinally, for applying an adjustable voltage with a longitudinally upward-opening parabolic distribution through them to drive the liquid crystal molecules in the lower liquid crystal cell to deflect longitudinally to form a refractive index with a longitudinally downward-opening parabolic distribution, so as to collimate the divergence angle of the slow axis of the incident light beam, and the adjustable voltage with the longitudinally upward-opening parabolic distribution is calculated based on the divergence angle of the slow axis; A third substrate shared between the upper and lower liquid crystal cells, the intermediate electrode layer thereon is grounded and forms an electric field distribution with the first and second strip electrodes respectively.

[0007] In some embodiments, it further includes a plurality of first voltage source units, the plurality of first strip electrodes are arranged horizontally in parallel and at equal distances, and are respectively connected to the corresponding first voltage source units one by one. Each of the first voltage source units outputs a positive voltage, and the absolute value of its voltage is distributed in a parabola with an upward opening along the arrangement direction of the plurality of first strip electrodes, and its voltage value is calculated based on the divergence angle of the fast axis of the incident light beam.

[0008] In some embodiments, it further includes a plurality of second voltage source units, the plurality of second strip electrodes are arranged longitudinally in parallel and at equal distances, and are respectively connected to the corresponding second voltage source units one by one. Each of the second voltage source units outputs a positive voltage, and the absolute value of its voltage is distributed in a parabola with an upward opening along the arrangement direction of the plurality of second strip electrodes, and its voltage value is calculated based on the divergence angle of the slow axis of the incident light beam.

[0009] In some embodiments, the voltage values applied by the first voltage source unit and the second voltage source unit are both within the range between the minimum voltage value (threshold voltage) for the deflection of the liquid crystal molecules and the saturation voltage value when the liquid crystal molecules reach the maximum torque.

[0010] In some embodiments, between the upper substrate and the third substrate, there are a first alignment layer, a first liquid crystal layer, and a second alignment layer stacked from top to bottom. The alignment directions of the first alignment layer and the second alignment layer are parallel and opposite, and the alignment direction of the first alignment layer is the same as the arrangement direction of the plurality of first strip electrodes.

[0011] In some embodiments, between the intermediate electrode layer and the lower substrate, there are a third alignment layer, a second liquid crystal layer, and a fourth alignment layer stacked from top to bottom. The alignment directions of the third alignment layer and the fourth alignment layer are parallel and opposite, and the alignment direction of the third alignment layer is the same as the arrangement direction of the plurality of second strip electrodes.

[0012] In some embodiments, the plurality of first strip electrodes form a first electrode layer, the plurality of second strip electrodes form a second electrode layer, and the first electrode layer, the second electrode layer, and the intermediate electrode layer are all laid on the upper substrate, the lower substrate, and the third substrate through a sputtering process.

[0013] On the other hand, an embodiment of the present invention further provides a method for collimating and shaping a laser beam, which is characterized in that a laser beam collimating and shaping device as described in any one of the foregoing is used, including: Obtain the fast-axis divergence angle and the slow-axis divergence angle of the incident beam; Based on the fast-axis divergence angle, determine the refractive index of the required transverse downward-opening parabolic distribution of the liquid crystal molecules in the upper liquid crystal cell, and based on this, determine the adjustable voltage of the corresponding transverse upward-opening parabolic distribution applied to the plurality of first strip electrodes to collimate the fast-axis divergence angle of the incident beam; Based on the slow-axis divergence angle, determine the refractive index of the required longitudinal downward-opening parabolic distribution of the liquid crystal molecules in the lower liquid crystal cell, and based on this, determine the adjustable voltage of the corresponding longitudinal upward-opening parabolic distribution applied to the plurality of second strip electrodes to collimate the slow-axis divergence angle of the incident beam and complete the shaping of the incident beam.

[0014] On the other hand, an embodiment of the present invention further provides a laser beam collimating and shaping system, including a laser beam collimating and shaping device array composed of a plurality of laser beam collimating and shaping devices as described in any one of the foregoing embodiments. The laser beam collimating and shaping device array is arranged in parallel with the laser unit array. The optical center of each laser beam collimating and shaping device is aligned with the optical axis of the corresponding laser unit. Each laser beam collimating and shaping device applies an adjustable voltage and is adapted to the beam divergence angle and the beam waist position of the corresponding laser unit to complete multi-beam parallel collimation and shaping.

[0015] In some embodiments, the laser beam collimating and shaping system includes a control unit for equalizing the beams with different main integral lens focal lengths through the following steps: Obtain the first distance between the main integral lens and the laser beam collimating and shaping system and the first focal length of the main integral lens; Based on the first distance and the first focal length, calculate the position of the focal plane of the laser beam collimating and shaping system through the equalization principle formula; By controlling the adjustable voltage applied to each device of the system, make the beam focus on the rear focal plane of the system after passing through the corresponding device and correspond to the front focal plane of the main integral lens, so as to achieve beam equalization on the rear focal plane of the main integral lens.

[0016] In some embodiments, the control unit is further configured to equalize the beams with different spot sizes through the following steps: Obtain the first size of the laser beam collimation and shaping device of the laser beam collimation and shaping system and the first focal length of the main integral lens; Based on the first size and the first focal length, calculate the position of the focal plane of the laser beam collimation and shaping system through the principle formula of homogenizing the spot; By controlling the adjustable voltage applied to each device of the system, make the beam focus on the rear focal plane of the system after passing through the corresponding device, and correspond to the front focal plane of the main integral lens, so as to achieve beam homogenization on the rear focal plane of the main integral lens.

[0017] The present invention has at least the following beneficial effects: A laser beam collimation and shaping device of the present application includes a double-layer liquid crystal cell structure with perpendicular focal planes stacked up and down, which includes an upper liquid crystal cell and a lower liquid crystal cell. The upper substrate of the upper liquid crystal cell is provided with a plurality of first strip electrodes arranged horizontally, which are used to drive the liquid crystal molecules in the upper liquid crystal cell to deflect horizontally through the applied adjustable voltage (an adjustable voltage with a horizontally opening parabola distribution applied based on the fast-axis divergence angle of the incident beam) to form a refractive index with a horizontally opening parabola distribution, so as to collimate the fast-axis divergence angle of the incident beam. It also includes a lower liquid crystal cell. The lower substrate of the lower liquid crystal cell is provided with a plurality of second strip electrodes arranged longitudinally, which are used to drive the liquid crystal molecules in the lower liquid crystal cell to deflect longitudinally through the applied adjustable voltage (an adjustable voltage with a vertically opening parabola distribution applied based on the slow-axis divergence angle of the incident beam) to form a refractive index with a vertically opening parabola distribution, so as to collimate the slow-axis divergence angle of the incident beam and complete the shaping of the incident beam. The upper liquid crystal cell and the lower liquid crystal cell share the third substrate in the middle. The middle electrode layer on the third substrate is grounded and forms an electric field distribution with the first and second strip electrodes respectively. Based on the double-layer liquid crystal cell structure, the present invention flexibly adjusts the adjustable voltage with an opening parabola distribution applied to the first strip electrode and the second strip electrode according to the different divergence angles of the incident beam, realizes flexible adjustment of the focal lengths of the liquid crystal lenses of the upper liquid crystal cell and the lower liquid crystal cell, and can collimate and shape the beams with different divergence angles without physically replacing the lens group or mechanically adjusting the lens spacing, and shape the elliptical spot into a circular spot, with high flexibility and self-adaptability.

[0018] A laser beam collimation and shaping method and system of the present invention can also achieve the above technical effects, which will not be elaborated here. Description of the Drawings

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other embodiments can be obtained based on these drawings.

[0020] Figure 1 The figure shows a three-dimensional view of a laser beam collimation and shaping device provided by an embodiment of the present invention; Figure 2 The figure shows a front view of a laser beam collimation and shaping device provided by another embodiment of the present invention; Figure 3 The figure shows a left view of a laser beam collimation and shaping device provided by another embodiment of the present invention; Figure 4 The figure shows a schematic diagram of collimating and shaping an incident elliptical beam based on a laser beam collimation and shaping device provided by another embodiment of the present invention; Figure 5 The figure shows a schematic diagram of several first strip electrodes in a top view arrangement respectively connected to corresponding first voltage source units provided by another embodiment of the present invention; Figure 6 The figure shows a schematic diagram of several second strip electrodes in a top view arrangement respectively connected to corresponding second voltage source units provided by another embodiment of the present invention; Figure 7 The figure shows a cross-sectional schematic diagram of the distribution of first and second liquid crystal molecules in the first and second liquid crystal layers when no voltage is applied to the first and second electrode layers provided by another embodiment of the present invention; Figure 8 The figure shows a longitudinal-sectional schematic diagram of the distribution of first and second liquid crystal molecules in the first and second liquid crystal layers when no voltage is applied to the first and second electrode layers provided by another embodiment of the present invention; Figure 9 The figure shows a schematic diagram of the voltage distribution V(x) of the first electrode layer corresponding to different voltage values applied by the first voltage source unit along the arrangement direction of the first strip electrode provided by another embodiment of the present invention; Figure 10 The figure shows a schematic diagram of the voltage distribution V(y) of the second electrode layer corresponding to different voltage values applied by the second voltage source unit along the arrangement direction of the second strip electrode provided by another embodiment of the present invention; Figure 11 The figure is a curve graph showing the change in the birefringence value of liquid crystal molecules with the increase of the applied voltage provided by another embodiment of the present invention; Figure 12Shown is a schematic diagram of the variation distribution of the deflection angle corresponding to the upward parabolic distribution of the simulated liquid crystal molecules with voltage provided by another embodiment of the present invention; Figure 13 Shown is a cross-sectional schematic diagram of the distribution of the first liquid crystal molecules in the first liquid crystal layer driven by the first voltage source provided by another embodiment of the present invention; Figure 14 Shown is a longitudinal-sectional schematic diagram of the distribution of the second liquid crystal molecules in the second liquid crystal layer driven by the second voltage source provided by another embodiment of the present invention; Figure 15 Shown is a schematic diagram of the two-dimensional refractive index distribution of the first liquid crystal molecules in the first liquid crystal layer driven by the first voltage source unit provided by another embodiment of the present invention; Figure 16 Shown is a schematic diagram of the two-dimensional refractive index distribution of the second liquid crystal molecules in the second liquid crystal layer driven by the second voltage source unit provided by another embodiment of the present invention; Figure 17 Shown is a schematic diagram of the process of collimating and shaping the light-emitting units in the semiconductor laser array by the liquid crystal lens array provided by another embodiment of the present invention; Figure 18 Shown is a schematic diagram of the process of homogenizing the semiconductor laser beam by the liquid crystal microlens array provided by another embodiment of the present invention.

[0021] Reference numerals: 100, first electrode element; 110, first electrode layer; 111, first strip electrode; 120, upper substrate; 130, first alignment layer; 200, first liquid crystal layer; 210, first liquid crystal molecules; 220, first adhesive layer group; 300, second electrode element; 310, second alignment layer; 320, third substrate; 330, intermediate electrode layer; 340, third alignment layer; 400, second liquid crystal layer; 410, second liquid crystal molecules; 420, second adhesive layer group; 500, third electrode element; 510, fourth alignment layer; 520, lower substrate; 530, second electrode layer; 531, second strip electrode; 1000, semiconductor laser; 1010, incident elliptical beam; 1021, upper liquid crystal cell; 1022, lower liquid crystal cell; 1030, output circular beam; 1101, first voltage source unit; 1102, second voltage source unit; 2000, liquid crystal lens array; 2010, semiconductor laser array; 2001, liquid crystal lens unit; 2011, semiconductor laser unit; 3000, liquid crystal microlens array; 3001, liquid crystal microlens unit; 3010, main integral lens. Detailed implementation manners

[0022] Embodiments of the present invention are described below. However, it should be understood that the disclosed embodiments are merely examples, and other embodiments may take various alternative forms.

[0023] In addition, it should be noted that the term "comprising", "including" or any other variation thereof is intended to cover non-exclusive inclusion, such that a process, method, article or apparatus comprising a series of elements includes not only those elements but also elements not expressly listed or inherent to such process, method, article or apparatus.

[0024] One or more embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0025] For the above purposes, in the first aspect of the embodiments of the present invention, an embodiment of a laser beam collimation and shaping device is proposed. Figure 1 The figure shows a perspective view of a laser beam collimation and shaping device provided by an embodiment of the present invention. Figure 2 The figure shows a front view of a laser beam collimation and shaping device provided by another embodiment of the present invention. Figure 3 The figure shows a left view of a laser beam collimation and shaping device provided by another embodiment of the present invention. Please refer to Figures 1-3, A laser beam collimation and shaping device includes a double-layer liquid crystal cell structure with mutually perpendicular focal planes stacked up and down, namely an upper liquid crystal cell 1021 and a lower liquid crystal cell 1022, as well as a third substrate 320 shared by both. Among them, a number of first strip electrodes are arranged horizontally on the upper substrate 120 of the upper liquid crystal cell 1021. An adjustable voltage with a horizontally opening parabola distribution is applied to the number of first strip electrodes to drive the liquid crystal molecules in the upper liquid crystal cell 1021 to deflect horizontally, forming a refractive index with a horizontally downward opening parabola distribution, so as to collimate the fast-axis divergence angle of the incident beam. The adjustable voltage with a horizontally opening parabola distribution is calculated based on the fast-axis divergence angle of the incident beam. The lower substrate 520 of the lower liquid crystal cell 1022 is provided with a number of second strip electrodes 531 arranged longitudinally. An adjustable voltage with a longitudinally opening parabola distribution is applied to the number of second strip electrodes 531 to drive the liquid crystal molecules in the lower liquid crystal cell 1022 to deflect longitudinally, forming a refractive index with a longitudinally downward opening parabola distribution, so as to collimate the slow-axis divergence angle of the incident beam and complete the shaping of the incident beam. The adjustable voltage with a longitudinally opening parabola distribution is calculated based on the slow-axis divergence angle of the incident beam. The upper liquid crystal cell 1021 and the lower liquid crystal cell 1022 share the third substrate 320 between them. The intermediate electrode layer 330 on the third substrate 320 is grounded as a common electrode, forming an electric field distribution with the first strip electrode 111 and the second strip electrode 531 respectively. Among them, the arrangement direction of the number of first strip electrodes 111 on the upper substrate 120 is perpendicular to the arrangement direction of the number of second strip electrodes 531 on the lower substrate 520. The upper substrate 120, the lower substrate 520 and the third substrate 320 are transparent substrates. At the same time, the transparent materials of the upper substrate 120, the lower substrate 520 and the third substrate 320 are not strictly limited and can be glass substrates, etc. Figure 4 The figure shows a schematic diagram of collimating and shaping an incident elliptical beam 1010 provided by another embodiment of the present invention based on a laser beam collimation and shaping device. Under the drive of the horizontally and longitudinally opening parabola voltages of the laser beam collimation and shaping device, due to the electro-optic birefringence characteristics, the liquid crystal molecules form a refractive index distribution with a downward opening parabola in the horizontal (horizontal direction) and vertical (vertical direction) directions respectively. The incident elliptical beam 1010 emitted by the semiconductor laser 1000 first passes through the upper liquid crystal cell 1021. The incident elliptical beam 1010 generates a phase difference at different positions in the upper liquid crystal cell 1021. The phase difference in the fast-axis direction presents a downward opening parabola distribution, compressing the fast-axis divergence angle to achieve fast-axis collimation. After the slow axis expands to the same width as the fast axis, the incident elliptical beam 1010 passes through the lower liquid crystal cell 1022. The phase difference in the slow-axis direction presents a downward opening parabola distribution, compressing the slow-axis divergence angle to achieve slow-axis collimation. The beam emitted from the lower liquid crystal cell 1022 is a collimated output circular beam 1030.

[0026] According to several embodiments of the present invention, it further includes several first voltage source units 1101. Several first strip electrodes 111 are arranged horizontally in parallel and at equal intervals. The several first strip electrodes 111 are respectively connected to the corresponding first voltage source units 1101 in a one-to-one correspondence. Figure 5 The figure shows a schematic diagram of the connection between several first strip electrodes 111 and the corresponding first voltage source units 1101 in a top view arrangement provided by another embodiment of the present invention. As Figure 5 shown, the positive electrodes of each first voltage source are connected to the corresponding first strip electrodes 111, and the negative electrodes are connected to the ground electrode through the connection intermediate electrode layer 330. The outputs of each first voltage source unit 1101 are all positive voltages and have different voltage values. It is intended to form an adjustable voltage with a parabola distribution opening upward horizontally on each first strip electrode 111. The voltage values output by each first voltage source unit 1101 are calculated based on the fast-axis divergence angle of the incident light beam. It can be understood that the number of the first strip electrodes 111 and the corresponding first voltage source units 1101 connected thereto is not limited to the number shown in the figure and can be increased or decreased according to actual needs.

[0027] According to several embodiments of the present invention, it further includes several second voltage source units 1102. Several second strip electrodes 531 are arranged horizontally in parallel and at equal intervals. The several second strip electrodes 531 are respectively connected to the corresponding second voltage source units 1102 in a one-to-one correspondence. Figure 6 The figure shows a schematic diagram of the connection between several second strip electrodes 531 and the corresponding second voltage source units 1102 in a top view arrangement provided by another embodiment of the present invention. As Figure 6 shown, the positive electrodes of each second voltage source are connected to the corresponding second strip electrodes 531, and the negative electrodes are connected to the ground electrode through the connection intermediate electrode layer 330. The outputs of each second voltage source unit 1102 are all positive voltages and have different voltage values. It is intended to form an adjustable voltage with a parabola distribution opening upward vertically on each second strip electrode 531. The voltage values output by each second voltage source unit 1102 are calculated based on the slow-axis divergence angle of the incident light beam. It can be understood that the number of the second strip electrodes 531 and the corresponding second voltage source units 1102 connected thereto is not limited to the number shown in the figure and can be increased or decreased according to actual needs.

[0028] According to several embodiments of the present invention, several first strip electrodes 111 form a first electrode layer 110, and several second strip electrodes 531 form a second electrode layer 530. The first electrode layer 110, the second electrode layer 530, and the intermediate electrode layer 330 are respectively deposited on the upper substrate 120, the lower substrate 520, and the third substrate 320 through a sputtering process. Between the upper substrate 120 and the third substrate 320, there are a first alignment layer 130, a first liquid crystal layer 200, and a second alignment layer 310 stacked from top to bottom. The alignment directions of the first alignment layer 130 and the second alignment layer 310 are parallel and opposite, and the alignment direction of the first alignment layer 130 is the same as the arrangement direction of several first strip electrodes 111. Between the intermediate electrode layer 330 and the lower substrate 520, there are a third alignment layer 340, a second liquid crystal layer 400, and a fourth alignment layer 510 stacked from top to bottom. The alignment directions of the third alignment layer 340 and the fourth alignment layer 510 are parallel and opposite, and the alignment direction of the third alignment layer 340 is the same as the arrangement direction of several second strip electrodes 531. More specifically, the first electrode element 100 includes the first electrode layer 110, the upper substrate 120, and the first alignment layer 130 stacked from top to bottom. The second electrode element 300 includes the second alignment layer 310, the third substrate 320, the intermediate electrode layer 330, and the third alignment layer 340 stacked from top to bottom. The third electrode element 500 includes the fourth alignment layer 510, the lower substrate 520, and the second electrode layer 530 stacked from top to bottom. The alignment directions of the two alignment layers in the upper liquid crystal cell 1021 and the lower liquid crystal cell 1022 are parallel and opposite, and the alignment directions between the upper liquid crystal cell 1021 and the lower liquid crystal cell 1022 are perpendicular to each other.

[0029] At both ends of the first liquid crystal layer 200, a first glue layer group 220 is symmetrically provided, which plays a role of fixing and supporting. The first glue layer group 220 is filled with first liquid crystal molecules 210. The injection process of the first liquid crystal molecules 210 is to first inject the voids flowing out of the spacers between the upper substrate 120 and the third substrate 320, and fix them through the first glue layer group 220, and then inject the first liquid crystal molecules 210 through the capillary principle; at both ends of the second liquid crystal layer 400, a second glue layer group 420 is symmetrically provided, which plays a role of fixing and supporting. The second glue layer group 420 is filled with second liquid crystal molecules 410. The injection process of the second liquid crystal molecules 410 is to first inject the voids flowing out of the spacers between the intermediate electrode layer 330 and the lower substrate 520, and fix them through the second glue layer group 420, and then inject the second liquid crystal molecules 410 through the capillary principle. Among them, the upper substrate 120, the third substrate 320, and the lower substrate 520 have all been coated with the first electrode layer 110, the intermediate electrode layer 330, and the second electrode layer 530 through the sputtering process. Since the alignment direction of the first alignment layer 130 is perpendicular to the alignment direction of the third alignment layer 340, the initial alignment directions of the first liquid crystal molecules 210 in the first liquid crystal layer 200 and the second liquid crystal molecules 410 in the second liquid crystal layer 400 are perpendicular to each other.

[0030] Figure 7 The cross-sectional schematic diagram shows the distribution of the first and second liquid crystal molecules 410 in the first and second liquid crystal layers 400 when the first and second electrode layers 530 provided by another embodiment of the present invention do not apply voltage. Figure 8 The longitudinal sectional schematic diagram shows the distribution of the first liquid crystal molecules 210 in the first liquid crystal layer 210 and the second liquid crystal molecules 410 in the second liquid crystal layer 400 when the first and second electrode layers 530 provided by another embodiment of the present invention do not apply voltage. Figures 7-8 It can be seen that when the first voltage source units 1101 respectively connected to several first strip electrodes 111 and the second voltage source units 1102 respectively connected to several second strip electrodes 531 are 0, the first liquid crystal molecules 210 in the upper liquid crystal cell 1021 and the second liquid crystal molecules 410 in the lower liquid crystal cell 1022 do not deflect, and due to the orientation effect of the alignment layer, their initial directions are perpendicular to each other. Figure 9 The schematic diagram shows the voltage distribution V(x) of the first electrode layer 110 corresponding to different voltage values applied by the first voltage source unit 1101 along the arrangement direction of the first strip electrode 111 provided by another embodiment of the present invention. Figure 10 The schematic diagram shows the voltage distribution V(y) of the second electrode layer 530 corresponding to different voltage values applied by the second voltage source unit 1102 along the arrangement direction of the second strip electrode 531 provided by another embodiment of the present invention. Figures 9-10It can be seen that the voltage V(x) of the first electrode layer 110 shows a parabola distribution with an upward opening along the transverse direction x, and the voltage V(y) of the first electrode layer 110 shows a parabola distribution with an upward opening along the longitudinal direction y. By applying different voltage values to the first strip electrode 111 and the second strip electrode 531 with a micron-level spacing, an approximately continuous parabola voltage distribution can be fitted in the respective arrangement directions of the first strip electrode 111 and the second strip electrode 531. The first liquid crystal molecules 210 of the first liquid crystal layer 200 are deflected with different voltages applied by the first voltage source unit 1101, and the second liquid crystal molecules 410 of the second liquid crystal layer 400 are deflected with different voltages applied by the second voltage source unit 1102, and then refractive index changes occur respectively. If n o (Ordinary Refractive Index) = 1.5, n e (Extraordinary Refractive Index) = 1.7, then the birefringence ∆n = n e - n o , Figure 11 is a graph showing the change in the birefringence value of the liquid crystal molecules with the increase of the applied voltage provided by another embodiment of the present invention. It can be seen from Figure 11 that when the voltage applied to the liquid crystal molecules is lower than the deflection voltage of the liquid crystal molecules, the liquid crystal molecules do not deflect and are arranged in parallel in the layer. At this time, the birefringence is a fixed value; when the voltage applied to the liquid crystal molecules increases to the minimum voltage value threshold voltage (deflection voltage) at which the liquid crystal molecules deflect, the liquid crystal molecules gradually deflect with the increase of the deflection voltage, so that the refractive index n‖ in the TE (Transverse Electric) polarization direction decreases from n e gradually, while the refractive index in the TM (Transverse Magnetic) polarization direction does not change under the action of the external electric field in the liquid crystal layer, that is, the refractive index n⊥ always remains n o unchanged; when the voltage applied to the liquid crystal molecules reaches the saturation voltage value corresponding to the maximum torque of the liquid crystal molecules, the birefringence no longer changes with the increase of the deflection voltage. Thus, it can be seen that the range of the voltage values applied by the first voltage source unit 1101 and the second voltage source unit 1102 should be between the minimum voltage value threshold voltage at which the liquid crystal molecules deflect and the saturation voltage value when the liquid crystal molecules reach the maximum torque. Figure 12 shows a schematic diagram of the change in the deflection angle corresponding to the parabola distribution of the simulated liquid crystal molecules with an upward opening with voltage provided by another embodiment of the present invention. As shown in Figure 12As shown, the deflection angle of the liquid crystal molecules changes as a parabola with an upward opening along with the voltage distribution. The central deflection angle is the smallest, and the edge deflection angle is the largest. When the voltage distributions on the first electrode layer 110 and the second electrode layer 530 are both greater than the threshold voltage V th , and show an upward-opening parabola distribution in the horizontal x and vertical y directions, the first liquid crystal molecules 210 in the upper liquid crystal cell 1021 and the second liquid crystal molecules 410 in the lower liquid crystal cell 1022 are both deflected, and the orientation directions change. The schematic diagram of the change in the orientation direction of the first liquid crystal molecules 210 along the horizontal direction is as shown in Figure 13 . The orientation distribution of the first liquid crystal molecules 210 is symmetric about the central plane of the upper liquid crystal cell 1021, and along the arrangement direction of the first strip electrode 111 units, the deflection angle gradually decreases from the edge of the upper liquid crystal cell 1021 to the center; the schematic diagram of the change in the orientation direction of the second liquid crystal molecules 410 along the vertical direction is as shown in Figure 14 . The orientation distribution of the second liquid crystal molecules 410 is symmetric about the central plane of the lower liquid crystal cell 1022, and along the arrangement direction of the second strip electrode 531 units, the deflection angle gradually decreases from the edge of the lower liquid crystal cell 1022 to the center. According to the relationship formula between the extraordinary light refractive index of the liquid crystal molecules and the deflection angle: (Formula 1) where is the extraordinary light refractive index of the liquid crystal molecules e, is the deflection angle of the liquid crystal molecules e, n o is the ordinary light refractive index, n e is the extraordinary light refractive index. The refractive index distributions of the liquid crystal molecules in the corresponding liquid crystal cells are calculated from Formula 1. As shown in Figure 15 is the schematic diagram of the two-dimensional refractive index distribution of the first liquid crystal molecules 210 in the first liquid crystal layer 200 driven by the first voltage source unit 1101. As shown in Figure 16 is the schematic diagram of the two-dimensional refractive index distribution of the second liquid crystal molecules 410 in the second liquid crystal layer 400 driven by the second voltage source unit 1102. It can be seen that the refractive index distributions of the first liquid crystal molecules 210 in the upper liquid crystal cell 1021 and the second liquid crystal molecules 410 in the lower liquid crystal cell 1022 are both approximately the refractive index distributions of cylindrical lenses. At the same time, the focal length of the approximate cylindrical lens in this embodiment can be regulated by the applied voltage, thereby realizing the collimation and shaping of incident light beams with different divergence angles.

[0031] The above laser beam collimation and shaping device is based on a double-layer liquid crystal cell structure. According to the different divergence angles of the incident beam, the adjustable voltages with an upward-opening parabola distribution applied to the first strip electrode 111 and the second strip electrode 531 are flexibly adjusted, so as to flexibly adjust the focal lengths of the liquid crystal lenses of the upper liquid crystal cell 1021 and the lower liquid crystal cell 1022. Without physically replacing the lens group or mechanically adjusting the lens spacing, the shaping of the elliptical spot of different laser beams can be realized, with high flexibility and self-adaptability. At the same time, compared with the traditional collimation and shaping lens group, the device has a simple structure, avoiding the problem of poor consistency of devices introduced by complex processes, which is beneficial to mass production. At the same time, the weight of the device of the present invention mainly comes from the liquid crystal layer and the substrate. Compared with the traditional shaping lens group, it is light in weight, small and convenient to carry. The liquid crystal layer is protected by its substrate, has a longer service life and wear resistance, and can be more conveniently integrated into the existing system or used in cooperation with other devices, with better compatibility.

[0032] In the second aspect of the embodiments of the present invention, a method for collimating and shaping a laser beam is proposed. A method for collimating and shaping a laser beam using the laser beam collimation and shaping device described in any one of the foregoing includes: Step S1, obtaining the fast-axis divergence angle and the slow-axis divergence angle of the incident beam; Step S2, determining the refractive index with a downward-opening parabola distribution in the horizontal direction required by the first liquid crystal molecules 210 of the upper liquid crystal cell 1021 based on the fast-axis divergence angle, and determining the adjustable voltages with a downward-opening parabola distribution in the horizontal direction applied to the corresponding first strip electrodes 111 based on this, so as to collimate the fast-axis divergence angle of the incident beam; Step S3, determining the refractive index with a downward-opening parabola distribution in the vertical direction required by the second liquid crystal molecules 410 of the lower liquid crystal cell 1022 based on the slow-axis divergence angle, and determining the adjustable voltages with a downward-opening parabola distribution in the vertical direction applied to the corresponding second strip electrodes 531 based on this, so as to collimate the slow-axis divergence angle of the incident beam and complete the shaping of the incident beam.

[0033] Specifically, in step S1, based on the fast-axis divergence angle, the refractive index distribution of the first liquid crystal molecules 210 of the first liquid crystal layer 200 of the upper liquid crystal cell 1021 is determined. Based on the refractive index distribution of the first liquid crystal molecules 210, their deflection angles are determined. Then, based on the deflection angles, the adjustable voltages with a downward-opening parabola distribution in the horizontal direction applied to the corresponding first strip electrodes 111 provided on the upper substrate 120 are determined, so as to collimate the fast-axis divergence angle of the incident beam.

[0034] Specifically, in step S3, based on the slow-axis divergence angle, the refractive index distribution of the second liquid crystal molecules 410 of the second liquid crystal layer 400 of the lower liquid crystal cell 1022 is determined. Based on the refractive index distribution of the second liquid crystal molecules 410, their deflection angles are determined. Then, based on the deflection angles, adjustable voltages with a vertically open parabola distribution applied to several second strip electrodes 531 provided on the lower substrate 520 are determined, so as to collimate the slow-axis divergence angle of the incident light beam and complete the shaping of the incident light beam.

[0035] In a third aspect of the embodiments of the present invention, a laser beam collimation and shaping system is proposed, which includes a laser beam collimation and shaping device array composed of several laser beam collimation and shaping devices as described in any of the foregoing embodiments. The laser beam collimation and shaping device array is arranged in parallel with the laser unit array. Among them, the laser unit array is obtained by integrating lasers into units and arraying them. The optical center of each laser beam collimation and shaping device is aligned with the optical axis of the corresponding laser unit. Each laser beam collimation and shaping device applies an adjustable voltage and is adapted to the beam divergence angle and beam waist position of the corresponding laser unit to complete multi-beam parallel collimation and shaping.

[0036] In a specific embodiment, such as Figure 17 , the liquid crystal lens array 2000 (a specific embodiment of the laser beam collimation and shaping system) is obtained by integrating laser beam collimation and shaping devices into units and then arraying them. The semiconductor laser array 2010 (a specific embodiment of the laser unit array) is obtained by integrating semiconductor lasers into units and arraying them. Each laser serves as a light-emitting unit of the semiconductor laser array 2010, and there will be differences in the beam divergence angles of the light-emitting units. The liquid crystal lens array 2000 includes several liquid crystal lens units 2001 (a specific embodiment of the laser beam collimation and shaping device) arranged in an array. The liquid crystal lens unit 2001 is used to collimate and shape the beam of the corresponding light-emitting unit of the semiconductor laser array 2010. Each liquid crystal lens unit 2001 at least includes the content of the foregoing laser beam collimation and shaping device, which will not be elaborated here. Several semiconductor laser units 2011 are arranged side by side to form the semiconductor laser array 2010. The light source of the semiconductor laser array 2010 is a high-power light source with a certain divergence angle. In order to compress the divergence angle of the light source of the semiconductor laser array 2010, the liquid crystal lens array 2000 is placed in parallel in front of it. The liquid crystal lens units 2001 are arranged side by side and correspond to the semiconductor laser units 2011 one by one. The corresponding relationship between the two units is as Figure 17As shown by the dashed box in the figure. Among them, for any pair of corresponding liquid crystal lens units 2001 and semiconductor laser units 2011, under the driving of the upper-opening parabolic voltage in the horizontal and vertical directions of the liquid crystal lens unit 2001, due to the electro-optic birefringence characteristic of the liquid crystal molecules, a lower-opening parabolic refractive index distribution is formed in the horizontal (horizontal direction) and vertical (vertical direction) respectively. The incident elliptical beam 1010 emitted by the semiconductor laser unit 2011 first passes through the upper liquid crystal cell 1021 of the liquid crystal lens unit 2001. The incident elliptical beam 1010 generates a phase difference at different positions in the upper liquid crystal cell 1021. The phase difference in the fast axis direction presents a lower-opening parabolic distribution, compressing the divergence angle of the fast axis and realizing fast axis collimation. After the slow axis expands to the same width as the fast axis, the incident elliptical beam 1010 passes through the lower liquid crystal cell 1022 of the liquid crystal lens unit 2001. The phase difference in the slow axis direction presents a lower-opening parabolic distribution, compressing the divergence angle of the slow axis and realizing slow axis collimation. The beam emitted from the lower liquid crystal cell 1022 is the collimated output circular beam 1030. In practical applications, due to the slight differences in the divergence angles of the semiconductor laser units 2011 of the semiconductor laser array 2010, according to the above process, an adjustable voltage with an upward-opening parabolic distribution is applied to each liquid crystal lens unit 2001 respectively, so that each liquid crystal lens unit 2001 collimates and shapes the beam of the corresponding semiconductor laser unit 2011. Therefore, the multi-beam parallel collimation and shaping of the semiconductor laser array 2010 are realized through the liquid crystal lens array 2000, thus overcoming the problems brought by the divergence angle differences of the semiconductor laser units 2011 of the semiconductor laser array 2010.

[0037] Among them, the steps of realizing multi-beam parallel collimation and shaping through the liquid crystal lens array 2000 include: Step S11, obtaining the divergence angle of the fast axis and the divergence angle of the slow axis of the incident laser beam of the semiconductor laser unit 2011; Step S12, determining the refractive index distribution of the first liquid crystal molecules 210 of the first liquid crystal layer 200 of the upper liquid crystal cell 1021 of the liquid crystal lens unit 2001 based on the divergence angle of the fast axis, determining the deflection angle of the first liquid crystal molecules 210 based on it, and determining the adjustable voltage with a horizontally upward-opening parabolic distribution applied to several first strip electrodes 111 based on the deflection angle to collimate the divergence angle of the fast axis of the incident beam; Step S13, determining the refractive index distribution of the second liquid crystal molecules 410 of the second liquid crystal layer 400 of the lower liquid crystal cell 1022 of the liquid crystal lens unit 2001 based on the divergence angle of the slow axis, determining the deflection angle of the second liquid crystal molecules 410 based on it, and determining the adjustable voltage with a vertically upward-opening parabolic distribution applied to several second strip electrodes 531 based on the deflection angle to collimate the divergence angle of the slow axis of the incident beam and complete the shaping of the incident beam; Step S14: Repeat steps S11 - S13 to control each liquid crystal lens unit 2001 to compress the divergence angles of the semiconductor laser units 2011 in the semiconductor laser array 2010 respectively to achieve collimation and shaping.

[0038] Integrate the laser beam collimation and shaping device into a unit and array it to obtain a liquid crystal lens array 2000. By controlling the voltages applied by each voltage source unit in each liquid crystal lens unit 2001, control the deflection angles of the first liquid crystal molecules 210 and the second liquid crystal molecules 410 in the upper liquid crystal cell 1021 and the lower liquid crystal cell 1022 of the liquid crystal lens unit 2001, form the refractive index distribution of the liquid crystal molecules in each liquid crystal cell, and make the overall structure approximately a combined structure of a liquid crystal cylindrical lens array with two mutually perpendicular focal planes, so as to achieve the collimation and shaping of the beams with different divergence angles of each light-emitting unit in the semiconductor laser array 2010.

[0039] In another specific embodiment, as Figure 18 , the liquid crystal microlens array 3000 (another specific embodiment of the laser beam collimation and shaping system) is obtained by integrating the laser beam collimation and shaping device into a unit and arraying it. The liquid crystal microlens array 3000 includes a number of liquid crystal microlens units 3001 (another specific embodiment of the laser beam collimation and shaping device) arranged in an array. The liquid crystal microlens array 3000 cooperates with the main integrating lens 3010 to achieve the homogenization of the semiconductor laser beam. Each liquid crystal microlens unit 3001 at least includes the content of the aforementioned laser beam collimation and shaping device, which will not be elaborated here. Since the electrode structures and arrangement methods of each liquid crystal microlens unit 3001 in the liquid crystal microlens array 3000 required for the homogenization of the semiconductor laser beam are the same, the electrodes of each liquid crystal microlens unit 3001 can be controlled uniformly, that is, the same voltage distribution is applied to the electrodes of each liquid crystal microlens unit 3001. The size of the liquid crystal microlens unit 3001 is D, the focal length is f, the focal length of the main integrating lens 3010 is F, and the size of the homogenized light spot is H. The liquid crystal microlens array 3000 is placed perpendicular to the optical axis. Assume that the light source is a collimated semiconductor laser beam, which is incident parallel to the optical axis into the microlens array 3000. The incident beam passes through a number of identical liquid crystal microlens units 3001 respectively, which is equivalent to passing through a number of coaxial transverse x and longitudinal y cylindrical lens pairs arranged in sequence. After passing through the liquid crystal microlens array 3000, the incident beam is divided into many sub-beams, and after exiting, it is focused on a focal plane perpendicular to the optical axis direction. This focal plane coincides with the front focal plane of the main integrating lens 3010, so the sub-beams are superimposed and homogenized on its rear focal plane after passing through the main integrating lens 3010.

[0040] According to several embodiments of the present invention, the liquid crystal microlens array 3000 further includes a control unit, and the control unit is used to homogenize the light beams with different focal lengths F of the main integral lenses 3010 through the following steps: Obtain the first distance L between the main integral lens 3010 and the liquid crystal microlens array 3000 and the first focal length F of the main integral lens 3010; Based on the first distance L and the first focal length F, calculate the position of the focal plane of the liquid crystal microlens array 3000 through the homogenization principle formula f = L - F; By controlling the adjustable voltage applied to each liquid crystal microlens unit 3001 of the liquid crystal microlens array 3000, make the light beam focus on the rear focal plane of the liquid crystal microlens array 3000 after passing through the corresponding liquid crystal microlens unit 3001, and correspond to the front focal plane of the main integral lens 3010, so as to achieve light beam homogenization on the rear focal plane of the main integral lens 3010.

[0041] According to several embodiments of the present invention, the control unit of the liquid crystal microlens array 3000 is further used to homogenize the light beams with different spot sizes H through the following steps: Obtain the first size D of the liquid crystal microlens unit 3001 of the liquid crystal microlens array 3000 and the first focal length F of the main integral lens 3010; Based on the first size D and the first focal length F, calculate the position of the focal plane of the liquid crystal microlens array 3000 through the homogenization spot principle formula H = -F * D / f; By controlling the adjustable voltage applied to each liquid crystal microlens unit 3001 of the liquid crystal microlens array 3000, make the light beam focus on the rear focal plane of the liquid crystal microlens array 3000 after passing through the corresponding liquid crystal microlens unit 3001, and correspond to the front focal plane of the main integral lens 3010, so as to achieve light beam homogenization on the rear focal plane of the main integral lens 3010.

[0042] Integrate the laser beam collimation and shaping device into a unit and array it to obtain the liquid crystal microlens array 3000. By centrally and uniformly controlling the voltage applied by each voltage source unit in each liquid crystal microlens unit 3001, control the deflection angles of the first liquid crystal molecules 210 and the second liquid crystal molecules 410 in the upper liquid crystal cell 1021 and the lower liquid crystal cell 1022 of the liquid crystal microlens unit 3001, form the refractive index distribution of the liquid crystal molecules in each liquid crystal cell, and then focus the vertically incident semiconductor laser beam on a focal plane perpendicular to the optical axis direction, and this focal plane coincides with the front focal plane of the main integral lens 3010, so as to achieve the homogenization of the semiconductor laser beam with different focal lengths F of different main integral lenses 3010 or different required homogenized spot sizes H.

[0043] Finally, it should be noted that those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The program for setting system parameters can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above methods. Among them, the storage medium of the program can be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM), etc. The embodiments of the above computer program can achieve the same or similar effects as the corresponding foregoing method embodiments.

[0044] In addition, the method disclosed according to the embodiments of the present invention can also be implemented as a computer program executed by a processor, and the computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the above functions defined in the method disclosed in the embodiments of the present invention are executed.

[0045] In addition, the above method steps and system units can also be implemented by using a controller and a computer-readable storage medium for storing a computer program that enables the controller to implement the above step or unit functions.

[0046] Those skilled in the art will also understand that the various exemplary logical blocks, modules, circuits, and algorithm steps described in connection with the disclosure herein can be implemented as electronic hardware, computer software, or a combination of both. To clearly illustrate this interchangeability of hardware and software, a general description of the functions of various illustrative components, blocks, modules, circuits, and steps has been given. Whether this function is implemented as software or as hardware depends on the specific application and the design constraints imposed on the overall system. The functions that can be implemented in various ways for each specific application by those skilled in the art, but this implementation decision should not be construed as causing a departure from the scope of the disclosure of the embodiments of the present invention.

[0047] In one or more exemplary designs, the functions may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted via a computer-readable medium as one or more instructions or code. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one location to another. The storage media may be any available media that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, the computer-readable media may comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a general purpose or special purpose computer or a general purpose or special purpose processor. In addition, any connection is properly termed a computer-readable medium. For example, if software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. As used herein, disk and disc include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0048] The above are exemplary embodiments disclosed by the present invention. However, it should be noted that various changes and modifications can be made without departing from the scope of the embodiments disclosed by the present invention as defined by the claims. The functions, steps, and / or actions of the method claims according to the disclosed embodiments herein need not be performed in any particular order. In addition, although the elements disclosed by the embodiments of the present invention may be described or claimed in individual form, they may also be understood as plural unless explicitly limited to the singular.

[0049] It should be understood that as used herein, unless the context clearly supports the exception, the singular form "a" is also intended to include the plural form. It should also be understood that the "and / or" used herein refers to any and all possible combinations of one or more of the associated listed items.

[0050] The serial numbers of the above disclosed embodiments of the present invention are merely for description and do not represent the superiority or inferiority of the embodiments.

[0051] Those of ordinary skill in the art can understand that all or part of the steps to implement the above embodiments can be completed by hardware, or can be completed by instructing relevant hardware through a program. The program can be stored in a computer-readable storage medium. The above-mentioned storage medium can be a read-only memory, a magnetic disk, an optical disk, or the like.

[0052] Those of ordinary skill in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope (including the claims) disclosed by the embodiments of the present invention is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other variations in different aspects of the embodiments of the present invention as described above, which are not provided in detail for the sake of brevity. Therefore, any omission, modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiments of the present invention shall be included in the protection scope of the embodiments of the present invention.

Claims

1. A laser beam collimation and shaping device, characterized in that, Comprising: An upper liquid crystal cell, the upper liquid crystal cell includes an upper substrate, and a plurality of first strip electrodes arranged horizontally are provided on the upper substrate, which are used to apply an adjustable voltage with a horizontally opening parabola distribution through them, drive the liquid crystal molecules in the upper liquid crystal cell to deflect horizontally to form a refractive index with a horizontally downward opening parabola distribution, so as to collimate the fast-axis divergence angle of the incident light beam, and the adjustable voltage with the horizontally opening parabola distribution is calculated based on the fast-axis divergence angle; A lower liquid crystal cell, the lower liquid crystal cell includes a lower substrate, and a plurality of second strip electrodes arranged vertically are provided on the lower substrate, which are used to apply an adjustable voltage with a vertically opening parabola distribution through them, drive the liquid crystal molecules in the lower liquid crystal cell to deflect vertically to form a refractive index with a vertically downward opening parabola distribution, so as to collimate the slow-axis divergence angle of the incident light beam, and the adjustable voltage with the vertically opening parabola distribution is calculated based on the slow-axis divergence angle; A third substrate shared between the upper and lower liquid crystal cells, and the intermediate electrode layer thereon is grounded and forms an electric field distribution with the first and second strip electrodes respectively.

2. The laser beam collimation and shaping device according to claim 1, characterized in that It further includes a plurality of first voltage source units, the plurality of first strip electrodes are arranged horizontally in parallel and at equal intervals, and are respectively connected to the corresponding first voltage source units one by one. Each of the first voltage source units outputs a positive voltage, and the absolute value of its voltage is distributed in a parabola with an upward opening along the arrangement direction of the plurality of first strip electrodes, and its voltage value is calculated based on the fast-axis divergence angle of the incident light beam.

3. The laser beam collimation and shaping device according to claim 2, wherein It further includes a plurality of second voltage source units, the plurality of second strip electrodes are arranged vertically in parallel and at equal intervals, and are respectively connected to the corresponding second voltage source units one by one. Each of the second voltage source units outputs a positive voltage, and the absolute value of its voltage is distributed in a parabola with an upward opening along the arrangement direction of the plurality of second strip electrodes, and its voltage value is calculated based on the slow-axis divergence angle of the incident light beam.

4. The laser beam collimation and shaping device according to claim 3, characterized in that The voltage values applied by the first voltage source unit and the second voltage source unit are both within the range between the minimum voltage value (threshold voltage) for the deflection of the liquid crystal molecules and the saturation voltage value when the liquid crystal molecules reach the maximum torque.

5. The laser beam collimation and shaping device according to claim 1, characterized in that, Between the upper substrate and the third substrate, there are a first alignment layer, a first liquid crystal layer, and a second alignment layer stacked from top to bottom. The alignment directions of the first alignment layer and the second alignment layer are parallel and opposite, and the alignment direction of the first alignment layer is the same as the arrangement direction of the plurality of first strip electrodes.

6. The laser beam collimation and shaping device according to claim 5, characterized in that, Between the intermediate electrode layer and the lower substrate, there are a third alignment layer, a second liquid crystal layer, and a fourth alignment layer stacked from top to bottom. The alignment directions of the third alignment layer and the fourth alignment layer are parallel and opposite, and the alignment direction of the third alignment layer is the same as the arrangement direction of the plurality of second strip electrodes.

7. The laser beam collimation and shaping device according to claim 1, characterized in that, The plurality of first strip electrodes form a first electrode layer, the plurality of second strip electrodes form a second electrode layer, and the first electrode layer, the second electrode layer, and the intermediate electrode layer are all laid on the upper substrate, the lower substrate, and the third substrate through a sputtering process.

8. A laser beam collimation and shaping method, characterized in that, Using the laser beam collimation and shaping device according to any one of claims 1-7, comprising: Obtain the fast-axis divergence angle and slow-axis divergence angle of the incident light beam; Based on the fast-axis divergence angle, determine the refractive index of the downward-opening parabola distribution required for the liquid crystal molecules in the upper liquid crystal cell. Based on this, determine the adjustable voltage of the upward-opening parabola distribution applied to the corresponding plurality of first strip electrodes to collimate the fast-axis divergence angle of the incident light beam; Based on the slow-axis divergence angle, determine the refractive index of the downward-opening parabola distribution required for the liquid crystal molecules in the lower liquid crystal cell. Based on this, determine the adjustable voltage of the upward-opening parabola distribution applied to the corresponding plurality of second strip electrodes to collimate the slow-axis divergence angle of the incident light beam and complete the shaping of the incident light beam.

9. A laser beam collimation and shaping system, characterized in that, It includes a laser beam collimation and shaping device array composed of a plurality of laser beam collimation and shaping devices as described in any one of claims 1-7. The laser beam collimation and shaping device array is arranged in parallel with the laser unit array. The optical center of each laser beam collimation and shaping device is aligned with the optical axis of the corresponding laser unit. Each laser beam collimation and shaping device applies an adjustable voltage and is adapted to the beam divergence angle and beam waist position of the corresponding laser unit to complete the multi-beam parallel collimation and shaping.

10. The laser beam collimation and shaping system according to claim 9, characterized in that, It includes a control unit for beam homogenization of different main integral lens focal lengths through the following steps: Obtain the first distance between the main integral lens and the laser beam collimation and shaping system and the first focal length of the main integral lens; Based on the first distance and the first focal length, calculate the position of the focal plane of the laser beam collimation and shaping system through the homogenization principle formula; By controlling the adjustable voltage applied to each device in the system, make the light beam focus on the rear focal plane of the system after passing through the corresponding device and correspond to the front focal plane of the main integral lens to achieve beam homogenization on the rear focal plane of the main integral lens.

11. The laser beam collimation and shaping system according to claim 10, wherein The control unit is further used for beam homogenization of different spot sizes through the following steps: Obtain the first size of the laser beam collimation and shaping device of the laser beam collimation and shaping system and the first focal length of the main integral lens; Based on the first size and the first focal length, calculate the position of the focal plane of the laser beam collimation and shaping system through the spot homogenization principle formula; By controlling the adjustable voltage applied to each device in the system, make the light beam focus on the rear focal plane of the system after passing through the corresponding device and correspond to the front focal plane of the main integral lens to achieve beam homogenization on the rear focal plane of the main integral lens.

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