Vortex laser generating device based on intracavity spherical aberration technology

Abstract

The utility model discloses a vortex laser generating device based on intracavity spherical aberration technology, which comprises a laser resonant cavity, a laser crystal, a vortex light adjusting assembly and a pump laser adjusting assembly used for generating focusing pump laser beams, the laser resonant cavity comprises an input mirror and an output mirror, the laser crystal is arranged between the input mirror and the output mirror, and the pump laser adjusting assembly is used for generating focusing pump laser beams. The vortex light adjusting assembly is arranged between the laser crystal and the output mirror, the vortex light adjusting assembly comprises a laser collimating mirror and a spherical aberration lens, the laser collimating mirror collimates divergent laser to collimated laser away from the laser crystal, the spherical aberration lens converts the collimated laser to spherical aberration laser with target spherical aberration, and the position of the spherical aberration lens in the laser resonant cavity is adjustable; the output mirror outputs the vortex laser of the target order obtained after oscillation, order adjustment of the output vortex laser of the target order can be achieved, and the laser has the advantage of being high in purity.

Description

Technical Field

[0001] The utility model belongs to the technical field of vortex laser, and particularly relates to a vortex laser generating device based on intracavity spherical aberration technology Background Art

[0002] Vortex laser has a new dimension of angular momentum and has broad application prospects in multiple optical application fields such as optical communication, quantum entanglement, and strong-field physics. Higher-purity vortex laser can obtain more accurate experimental results and achieve high-precision laser manipulation, which is of great value to multiple fields using vortex laser. The vortex laser with adjustable order facilitates the adjustment of the mode of the vortex laser according to the application scenario at any time, and improves the utilization efficiency of the vortex laser. However, the problems faced by the current methods for generating vortex laser are that on the one hand, the purity of the vortex laser is relatively low, and on the other hand, the order of the vortex laser cannot be flexibly adjusted Summary of the Utility Model

[0003] Aiming at the deficiencies of the prior art, the purpose of the utility model is to provide a vortex laser generating device based on intracavity spherical aberration technology, which solves the problems of non-adjustable order and low purity of vortex laser in the prior art

[0004] The present application provides a vortex laser generating device based on intracavity spherical aberration technology, including a pump laser adjusting component, a laser resonator cavity, a laser crystal, and a vortex light adjusting component. The pump laser adjusting component is used to generate focused pump laser. The laser resonator cavity includes an input mirror and an output mirror. The input mirror is arranged between the pump laser adjusting component and the output mirror. The laser crystal is arranged between the input mirror and the output mirror. The vortex light adjusting component is arranged between the laser crystal and the output mirror. The vortex light adjusting component includes a laser collimating mirror and a spherical aberration lens arranged in sequence away from the laser crystal. The laser crystal is used to absorb the pump laser and emit target laser. The target laser is a divergent laser beam. The laser collimating mirror is used to collimate the divergent laser into collimated laser. The curvature of the spherical aberration lens is greater than that of the laser collimating mirror. The spherical aberration lens is used to convert the collimated laser into spherical aberration laser with target spherical aberration. The position of the spherical aberration lens in the laser resonator cavity is adjustable to change the oscillation condition of the laser resonator cavity for the spherical aberration laser, so that the output mirror outputs vortex laser of the target order after oscillation, wherein the spherical aberration laser has a spot with a target size

[0005] In some embodiments, the pump laser adjustment assembly includes a pump laser source, a pump collimating mirror, and a pump focusing mirror. The pump laser source is configured to generate divergent pump laser. The pump collimating mirror is disposed between the pump laser source and the pump focusing mirror and is configured to collimate the divergent pump laser to obtain collimated pump laser. The pump focusing mirror is disposed between the pump collimating mirror and the input mirror and is configured to focus the collimated pump laser to obtain focused pump laser. The input mirror is disposed between the pump focusing mirror and the laser crystal and is configured to transmit the focused pump laser to the laser crystal while reflecting the target laser.

[0006] In some embodiments, the laser collimating mirror is configured as a plano-convex lens with a convex first side and a flat second side. The first side and the second side are two opposite sides, and the convex side of the laser collimating mirror faces the laser crystal.

[0007] In some embodiments, the spherical aberration lens is configured as a plano-convex lens with a convex third side and a flat fourth side. The third side and the fourth side are two opposite sides, and the flat side of the spherical aberration lens faces the laser crystal.

[0008] In some embodiments, the position of the output mirror is adjustable to change the relative distance between the output mirror and the spherical aberration lens.

[0009] In some embodiments, the position of the spherical aberration lens in the laser resonator is adjustable, and the position of the spherical aberration lens between the laser collimating mirror and the output mirror is adjustable.

[0010] In some embodiments, the input mirror is configured as a plano-concave lens with a flat fifth side and a concave sixth side. The fifth side and the sixth side are two relatively arranged sides, and the concave side of the input mirror faces the laser crystal.

[0011] In some embodiments, the material of the spherical aberration lens is a combined material of multiple materials.

[0012] In some embodiments, the curvature of the axis position of the spherical aberration lens is different from the curvature of the outer periphery of the spherical aberration lens.

[0013] In some embodiments, a transmission film is coated on the spherical aberration lens, and the transmission film is configured to achieve a transmission of more than 99% of the spherical aberration laser beam.

[0014] The beneficial effects of the present utility model include but are not limited to the following: (1) In this application, the position of the spherical aberration lens in the laser resonator is adjustable, which can provide a flexible method to adjust the oscillation conditions of the laser to meet different application requirements; further, the required spherical aberration can be introduced through the spherical aberration lens, and the oscillation conditions of the laser mode can be controlled to selectively enhance or suppress specific high-order modes, thereby generating vortex lasers of specific orders; (2) The laser crystal absorbs and focuses the pump laser and emits the target laser, and the target laser is a divergent laser beam, which is then collimated by the laser collimator, ensuring the effective utilization and conversion of laser energy; (3) The device in this application compactly integrates the laser crystal, the laser collimator, and the spherical aberration lens in the laser resonator, saving space and facilitating system integration; (4) In this application, through pump collimation and focusing, the loss of the pump light is reduced, and the overall energy conversion efficiency of the laser is improved; (5) By adjusting the positions of the output mirror and the spherical aberration lens, the optical path length and spherical aberration distribution in the cavity can be changed, thereby flexibly controlling the laser mode. Further, by controlling the relative positions of the output mirror and the spherical aberration lens as required, the competitive advantage of the required mode can be optimized, and the purity of the required laser mode can be improved; further, by appropriately adjusting the relative positions, the overlap between the pump light and the laser mode can be optimized, improving the pump efficiency and the laser output power. (6) In this application, the material of the spherical aberration lens can be a combination of multiple materials. Using a combination of multiple materials can provide different optical properties, such as refractive index, dispersion, etc., which helps to increase the spherical aberration, improve the spherical aberration between different modes, make the lasers of different orders more distinguishable, thereby enhancing the selectivity for specific-order vortex modes, suppressing other non-target modes, and flexibly generating target vortex lasers of different orders. Moreover, the combination of different materials makes the light inside and outside experience different optical paths, resulting in a larger spherical aberration. A larger spherical aberration can make the difference between different modes greater, so higher-purity vortex lasers can be obtained; (7) The design with different axial and peripheral curvatures helps to generate a larger phase gradient between the center and the edge of the laser beam, thereby more effectively introducing the required spherical aberration, enhancing the selectivity for specific-order vortex modes, suppressing the lasers of other non-target modes, and obtaining higher-purity vortex lasers; (8) In this application, a light-transmitting film is coated on the spherical aberration lens, which can achieve a high transmittance of the spherical aberration laser beam, reduce the loss of the beam in the lens, thereby improving the conversion efficiency of the spherical aberration laser beam to the vortex laser of the target order. Further, the transmission film can serve as a protective film for the spherical aberration lens, reducing the heat accumulation in the spherical aberration lens, playing a certain protective role for the spherical aberration lens, and preventing the lens from being affected by heat accumulation and reducing the adjustment accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art.

[0016] Figure 1 It is a schematic diagram of the principle of the spherical aberration lens selection mode;

[0017] Figure 2 It is a schematic diagram of a vortex laser generating device based on the intracavity spherical aberration technology according to an embodiment of the present invention;

[0018] Figure 3 It is another schematic diagram of a vortex laser generating device based on the intracavity spherical aberration technology according to an embodiment of the present invention;

[0019] Figure 4 It is another schematic diagram of a vortex laser generating device based on the intracavity spherical aberration technology according to an embodiment of the present invention;

[0020] Figure 5 It is a schematic diagram of the principle of the spherical aberration lens selection mode based on different combinations of multiple materials;

[0021] Figure 6 It is a schematic diagram of the principle of the spherical aberration lens selection mode in which the curvature of the axial center position of the spherical aberration lens is different from the outer peripheral curvature of the spherical aberration lens;

[0022] Among them, 1 - pump laser source, 2 - pump collimating mirror, 3 - pump focusing mirror, 4 - input mirror, 5 - laser crystal, 6 - laser collimating mirror, 7 - spherical aberration lens, 8 - output mirror, 9 - vortex laser of the target order. Specific embodiments

[0023] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0024] It can be understood that using a plano - convex lens with a large spherical aberration (spherical aberration lens 7) in the laser resonator cavity can change the laser intensity distribution and mode volume, so that the optical paths of different order modes are spatially separated for mode selection. For example, Figure 1 as shown, when a beam of light with a large diameter passes through the spherical aberration lens 7 as shown in Figure 1 and is focused, the converging ability of the central region and the edge region of the spherical aberration lens 7 to the light beam is different. The off - axis light beam is refracted much more severely than the paraxial light beam when passing through the spherical aberration lens 7. Therefore, the electromagnetic waves scattered from the same object point do not converge at one point after passing through the spherical aberration lens 7, but become a diffused circular spot on the phase plane of the spherical aberration lens 7. For the high - order mode lasers of different orders in the laser, the beam distribution position extends outward from the optical axis as the order increases, and the position of the optical axis is the fundamental mode laser. As shown in Figure 1As shown, due to the different laser foci at different positions (modes), only part of the laser passing through the mirror can be reflected. The laser with the focus exactly at the mirror position can be reflected along the original optical path, while the lasers of other modes are scattered, and thus only the laser with the focus exactly at the mirror position can oscillate, and the oscillations of the lasers of other modes are suppressed. Therefore, by controlling the spherical aberration of the resonant cavity, the selection of the laser oscillation mode can be achieved.

[0025] Specifically, the vortex laser generating device based on the intracavity spherical aberration technology provided by this application, as Figures 2 to 4 shown, includes a pump laser adjusting component, a laser crystal 5, a laser resonator cavity, and a vortex light adjusting component. The pump laser adjusting component is used to generate focused pump laser. The laser resonator cavity includes an input mirror 4 and an output mirror 8. The input mirror 4 is arranged between the pump laser adjusting component and the output mirror 8. The laser crystal 5 is arranged between the input mirror 4 and the output mirror 8. The vortex light adjusting component is arranged between the laser crystal 5 and the output mirror 8. The vortex light adjusting component includes a laser collimating mirror 6 and a spherical aberration lens 7 arranged in sequence away from the laser crystal. The laser crystal 5 is used to absorb the focused pump laser and emit target laser, and the target laser is divergent laser. The laser collimating mirror 6 is used to collimate the divergent laser into collimated laser. The curvature of the spherical aberration lens 7 is greater than that of the laser collimating mirror 6. The spherical aberration lens 7 is used to convert the collimated laser into spherical aberration laser with target spherical aberration. The position of the spherical aberration lens 7 in the laser resonator cavity is adjustable to change the oscillation condition of the laser resonator cavity for the spherical aberration laser, so that the output mirror 8 outputs the vortex laser 9 of the target order after oscillation, wherein the spherical aberration laser has a spot with a target size. In the embodiment of this application, the position of the spherical aberration lens 7 in the laser resonator cavity is adjustable, which can provide a flexible method to adjust the oscillation condition of the laser to meet different application requirements; further, the required spherical aberration can be introduced through the spherical aberration lens 7, the oscillation condition of the laser mode can be controlled, and specific high-order modes can be selectively enhanced or suppressed, so as to generate the vortex laser of a specific order. In this embodiment, the distance between the lens spherical aberration and the output mirror 8 is d 1 .

[0026] Based on the above principle, in this scheme, except for the laser of the target mode, the lasers of other modes are suppressed, so this scheme can obtain high-purity vortex laser.

[0027] In some embodiments, the pump beam generating assembly includes a pump laser source 1, a pump collimating mirror 2, and a pump focusing mirror 3. The pump laser source 1 is used to generate divergent pump laser. The pump collimating mirror 2 is disposed between the pump laser source 1 and the pump focusing mirror 3. The pump collimating mirror 2 is used to collimate the divergent pump laser to obtain collimated pump laser. The pump focusing mirror 3 is disposed between the pump collimating mirror 2 and the input mirror 4. The pump focusing mirror 3 is used to focus the collimated pump laser to obtain focused pump laser. The input mirror 4 is disposed between the pump focusing mirror 3 and the laser crystal 5. The input mirror 4 is used to transmit the focused pump laser to the laser crystal 5. It can be understood that the laser crystal 5 absorbs the pump laser beam and emits the target laser. The target laser is a divergent laser beam, which is collimated by the laser collimating mirror 6 to ensure the effective utilization and conversion of laser energy. Further, the device of the present application compactly integrates the laser crystal 5, the laser collimating mirror 6, and the spherical aberration lens 7 in the laser resonator cavity, saving space and facilitating system integration. Further, in the embodiments of the present application, through pump collimation and focusing, the loss of pump light is reduced, and the overall energy conversion efficiency of the laser is improved;

[0028] In some embodiments, the laser collimating mirror 6 is configured as a plano-convex lens with a convex first side and a flat second side. The first side and the second side are two opposite sides. The convex side of the laser collimating mirror 6 faces the laser crystal 5.

[0029] In some embodiments, the spherical aberration lens 7 is configured as a plano-convex lens with a convex third side and a flat fourth side. The third side and the fourth side are two opposite sides. The flat side of the spherical aberration lens 7 faces the laser crystal 5.

[0030] In some embodiments, continue to refer to Figure 3 , the position of the output mirror 8 is adjustable to change the relative distance between the output mirror 8 and the spherical aberration lens 7. In this embodiment, Figure 3 the distance between the output mirror 8 and the spherical aberration lens 7 is d 2 , d 2 < d 1 .

[0031] In some embodiments, continue to refer to Figure 4 , the position of the spherical aberration lens 7 in the laser resonator cavity is adjustable such that the position of the spherical aberration lens 7 between the laser collimating mirror 6 and the output mirror 8 is adjustable. In this embodiment, the spherical aberration lens 7 moves towards the output mirror 8. The distance between the spherical aberration lens 7 and the output mirror 8 is d 3 , where d 2 < d 3 < d 1 .

[0032] It can be understood that by adjusting the positions of the output mirror 8 and the spherical aberration lens 7, the optical path length and spherical aberration distribution in the cavity can be changed, thereby flexibly controlling the laser mode. Further, by controlling the relative positions of the output mirror 8 and the spherical aberration lens 7 as required, the competition of the required mode can be optimized, and the purity of the required laser mode can be improved. Further, by appropriately adjusting the relative positions, the spatial coincidence of the pump light and the laser mode can be optimized, and the pump efficiency and laser output power can be improved.

[0033] In some embodiments, the input mirror 4 is configured as a plano-concave lens with a flat fifth side and a concave sixth side. The fifth side and the sixth side are two opposite sides, and the concave side of the input mirror 4 faces the laser crystal 5.

[0034] In some embodiments, the material of the spherical aberration lens 7 is a combined material of multiple materials. Exemplarily, when the material of the spherical aberration lens 7 is a combined material of multiple materials, the schematic diagram of the selection mode of the spherical aberration lens 7 based on different combinations of multiple materials is as Figure 5 shown, where the dark part is the high refractive index material and the light part is the low refractive index material. It can be understood that the material of the spherical aberration lens 7 can be a combination of multiple materials. Using a combination of multiple materials can provide different optical properties, such as refractive index, dispersion, etc., which helps to increase the spherical aberration, increase the spherical aberration between different modes, make the distinction between different modes more obvious, thereby enhancing the selectivity for a specific order vortex mode, suppressing other non-target modes, and flexibly generating target vortex lasers of different orders. Moreover, the combination of different materials makes the light inside and outside experience different optical paths, resulting in a larger spherical aberration. A larger spherical aberration can make the difference between different modes greater, so a higher purity of vortex laser can be obtained;

[0035] In some embodiments, the curvature of the axial center position of the spherical aberration lens 7 is different from the curvature of the outer periphery of the spherical aberration lens 7. Exemplarily, the schematic diagram of the selection mode of the spherical aberration lens 7 with the curvature of the axial center position of the spherical aberration lens 7 different from the curvature of the outer periphery of the spherical aberration lens 7 is as Figure 6 shown. The curvature of the lens at the center position is larger, and the curvature of the outer side is lower. The design with different axial center curvature and outer periphery curvature helps to generate a larger phase gradient between the center and the edge of the laser beam, thereby more effectively introducing the required spherical aberration, enhancing the selectivity for a specific order vortex mode, suppressing the laser of other non-target modes, and obtaining a higher purity of vortex laser.

[0036] In some embodiments, a transmission film is coated on the spherical aberration lens 7, and the transmission film is used to achieve a transmission of more than 99% of the spherical aberration laser beam. In the embodiments of the present application, coating a light-transmitting film on the spherical aberration lens 7 can achieve a high transmittance of the spherical aberration laser beam, reduce the loss of the beam in the lens, thereby improving the conversion efficiency of the spherical aberration laser beam to the vortex laser 9 of the target order. Further, the transmission film can be used as a protective film for the spherical aberration lens 7, which plays a certain protective role for the spherical aberration lens 7, reduces the heat accumulation of the spherical aberration lens 7, plays a certain protective role for the spherical aberration lens 7, and prevents the lens from being affected by heat accumulation and reducing the adjustment accuracy.

[0037] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed.

Claims

1. A vortex laser generating device based on intracavity spherical aberration technology, characterized in that: The invention comprises a pump laser adjustment component, a laser crystal (5), a laser resonant cavity and a vortex light adjustment component, wherein the pump laser adjustment component is used to generate focused pump laser, the laser resonant cavity comprises an input mirror (4) and an output mirror (8), the input mirror (4) is arranged between the pump laser adjustment component and the output mirror (8), the laser crystal (5) is arranged between the input mirror (4) and the output mirror (8), the vortex light adjustment component is arranged between the laser crystal (5) and the output mirror (8), the vortex light adjustment component comprises a laser collimator (6) and a spherical aberration lens (7) which are arranged in sequence away from the laser crystal (5), and the The laser crystal (5) is used to absorb the focused pump laser and emit a target laser, wherein the target laser is a divergent laser. The laser collimator (6) is used to collimate the divergent laser into a collimated laser. The curvature of the spherical aberration lens (7) is greater than the curvature of the laser collimator. The spherical aberration lens (7) is used to convert the collimated laser into a spherical aberration laser having a target spherical aberration. The position of the spherical aberration lens (7) in the laser resonant cavity is adjustable to change the oscillation condition of the laser resonant cavity for the spherical aberration laser, so that the output mirror (8) outputs a vortex laser (9) of a target order obtained after oscillation, wherein the spherical aberration laser has a light spot of a target size.

2. The vortex laser generating device based on intracavity spherical aberration technology according to claim 1 is characterized in that: The pump laser adjustment component comprises a pump laser source (1), a pump collimator (2) and a pump focusing mirror (3). The pump laser source (1) is used to generate a divergent pump laser. The pump collimator (2) is arranged between the pump laser source (1) and the pump focusing mirror (3). The pump collimator (2) is used to collimate the divergent pump laser to obtain a collimated pump laser. The pump focusing mirror (3) is arranged between the pump collimator (2) and the input mirror (4). The pump focusing mirror (3) is used to focus the collimated pump laser to obtain the focused pump laser. The input mirror (4) is arranged between the pump focusing mirror (3) and the laser crystal (5). The input mirror (4) is used to transmit the focused pump laser to the laser crystal (5) and reflect the target laser at the same time.

3. The vortex laser generating device based on intracavity spherical aberration technology according to claim 2 is characterized in that: The laser collimator (6) is constructed as a plano-convex lens with a convex first side and a flat second side, the first side and the second side being two opposite sides, and the convex surface of the laser collimator (6) faces the laser crystal (5).

4. The vortex laser generating device based on intracavity spherical aberration technology according to claim 1, characterized in that: The spherical aberration lens (7) is constructed as a plano-convex lens with a convex third side and a flat fourth side, the third side and the fourth side are two opposite sides, and the plane of the spherical aberration lens (7) faces the laser crystal (5).

5. The vortex laser generating device based on intracavity spherical aberration technology according to claim 1 is characterized in that: The position of the output mirror (8) is adjustable to change the relative distance between the output mirror (8) and the spherical aberration lens (7).

6. The vortex laser generating device based on intracavity spherical aberration technology according to claim 1, characterized in that: The position of the spherical aberration lens (7) in the laser resonant cavity is adjustable, and the position of the spherical aberration lens (7) between the laser collimating mirror (6) and the output mirror (8) is adjustable.

7. The vortex laser generating device based on intracavity spherical aberration technology according to claim 2, characterized in that: The input mirror (4) is constructed as a plano-concave lens with a fifth side surface being a plane and a sixth side surface being a concave surface. The fifth side surface and the sixth side surface are two side surfaces arranged opposite to each other, and the concave surface of the input mirror (4) faces the laser crystal (5).

8. The vortex laser generating device based on intracavity spherical aberration technology according to claim 4 or 6, characterized in that: The material of the spherical aberration lens (7) is a combination of multiple materials.

9. The vortex laser generating device based on intracavity spherical aberration technology according to claim 4 or 6, characterized in that: The curvature of the axis center position of the spherical aberration lens (7) is different from the curvature of the periphery of the spherical aberration lens (7).

10. The vortex laser generating device based on intracavity spherical aberration technology according to claim 4 or 6, characterized in that: The spherical aberration lens (7) is coated with a transmission film, and the transmission film is used to achieve a transmission of more than 99% of the spherical aberration laser beam.

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