阅读说明：本技术 用于激光冲击的光斑整形装置及其方法 (Light spot shaping device and method for laser shock ) 是由 冯爱新 徐国秀 周远航 韩磊 王术新 潘晓铭 罗虹 张健 张成龙 吴成萌 于 2020-06-15 设计创作，主要内容包括：本发明涉及用于激光冲击的光斑整形装置及方法,在入光口与出光口之间设有用于光斑整形的微透镜阵列系统、用于调节光斑大小的整形元件、准直镜、聚焦镜,微透镜阵列系统置于电动滑台一上,可移动,整形元件包含依次等距平行错列布置的扩束镜一、扩束镜二及扩束镜三,置于电动滑台二上,可移动。激光束从入光口进入,由微透镜阵列系统将圆光斑整形为能量分布均匀的方光斑,通过电动滑台二扩束镜一、扩束镜二及扩束镜三的切换,调节光斑大小；若无需光斑整形,电动滑台一控制微透镜阵列系统移动,光束未经过微透镜阵列系统,光束直接经过整形元件输出圆光斑；激光器输出的光斑在圆光斑与方光斑的之间快速转换,光束转化效率高,光强分布均匀、平顶。(The invention relates to a light spot shaping device and a light spot shaping method for laser shock.A micro-lens array system for shaping light spots, a shaping element for adjusting the size of the light spots, a collimating lens and a focusing lens are arranged between a light inlet and a light outlet, the micro-lens array system is arranged on an electric sliding table I and can move, and the shaping element comprises a beam expanding lens I, a beam expanding lens II and a beam expanding lens III which are sequentially arranged on the electric sliding table II in parallel and staggered at equal intervals and can move. Laser beams enter from a light inlet, a round light spot is shaped into a square light spot with uniform energy distribution by a micro-lens array system, and the size of the light spot is adjusted by switching a first beam expander, a second beam expander and a third beam expander of an electric sliding table; if the light spot shaping is not needed, the electric sliding table I controls the micro-lens array system to move, the light beam does not pass through the micro-lens array system, and the light beam directly passes through the shaping element to output a round light spot; the light spot output by the laser is quickly converted between the round light spot and the square light spot, the light beam conversion efficiency is high, and the light intensity distribution is uniform and flat.)

1. A facula shaping device for laser shock, its characterized in that: be equipped with microlens array system (2) that are used for the facula plastic between income light mouth (1) and light-emitting mouth (8) in proper order, be used for adjusting plastic component (4), collimating mirror (5) and focusing mirror (6) of facula size, on electronic slip table (3) was arranged in microlens array system (2), it is portable, plastic component (4) contain beam expanding mirror (13), beam expanding mirror two (11) and beam expanding mirror three (9) that the parallel staggered arrangement of equidistance in proper order, arrange electronic slip table two (10) in on, portable.

2. The spot shaping device for laser shock according to claim 1, wherein: the microlens array system (2) comprises a microlens array (22) and a focal plane (23) which are arranged between a light inlet (21) and a light outlet (24).

3. The spot shaping device for laser shock according to claim 2, wherein: the micro-lens array (22) is formed by arranging and combining micro-lenses with aperture of micron-sized to hundred-micron-sized.

4. The spot shaping device for laser shock according to claim 3, wherein: the micro lenses of the micro lens array (22) are lenses with the transmittance of 532nm and 1064nm being more than 99.5%.

5. The spot shaping device for laser shock according to claim 2, wherein: the micro lens array (22) is a square micro lens array and converts laser beams from round light spots into square light spots.

6. The spot shaping device for laser shock according to claim 1, wherein: the first beam expander (13), the second beam expander (11) and the third beam expander (9) are fixed on the bottom plate (12), the bottom plate (12) is arranged on the second electric sliding table (10), the first beam expander (13) is positioned on the left side of the second beam expander (11), and the third beam expander (9) is positioned on the right side of the second beam expander (11); the distance between the central lines of the first beam expander (13) and the second beam expander (11) is 85mm, and the distance between the central lines of the third beam expander (9) and the second beam expander (11) is 85 mm; the distance between the oblique edges of the first beam expander (13) and the second beam expander (11) is 120mm, and the distance between the oblique edges of the third beam expander (9) and the second beam expander (11) is 120 mm; the focusing mirror (6) is arranged on the electric sliding table III (7) and can move.

7. A spot shaping method for laser shock, implemented with the apparatus of claim 1, characterized by: laser beams enter from a light inlet (1), round light spots are shaped into square light spots with uniform energy distribution by a micro-lens array system (2), switching of a beam expanding lens I (13), a beam expanding lens II (11) and a beam expanding lens III (9) of a shaping element is controlled through an electric sliding table II (10), the size of the light spots is adjusted, the light beams are collimated by a collimating lens (5), and the light beams are output after being focused by a focusing lens (6); if the spot shaping is not needed, the electric sliding table I (3) is used for controlling the micro-lens array system (2) to move, so that the light beam does not pass through the micro-lens array system (2), the light beam directly passes through the shaping element to output a round spot, the light beam is collimated by the collimating lens (5), the light beam is focused by the focusing lens (6) and then output, and the electric sliding table III (7) is used for driving the focusing lens (6) to change the size of the spot; the fast conversion of the light spot output by the laser between the round light spot and the square light spot is realized.

8. The spot shaping method for laser shock according to claim 7, characterized in that: the micro-lens array system (2) comprises a micro-lens array (22) and a focal plane (23), wherein the micro-lens array (22) and the focal plane (23) are arranged between a light inlet hole (21) and a light outlet hole (24), when incident light passes through the micro-lens array (22), the incident light is divided into a plurality of tiny sub-beams, the sub-beams are focused on the focal plane (23) through a focusing lens, and then square light spots are output from the light outlet hole (24).

9. The spot shaping method for laser shock according to claim 7, characterized in that: the micro-lens array (22) compresses the round light spots into square light spots in two directions, the light intensity of the obtained square light spots is in flat-top distribution, and the fluctuation of the light intensity flat-top distribution is 98% +/-2%.

10. The spot shaping method for laser shock according to claim 7, characterized in that: and the beam expander I (13), the beam expander II (11) and the beam expander III (9) are arranged on the electric sliding table II (10), and are driven to move through the electric sliding table II (10), and the size of the adjusting light spot is respectively 3mm, 4mm and 5 mm.

Technical Field

The invention relates to a light spot shaping device and a light spot shaping method for laser shock, and belongs to the technical field of laser shock processing.

Background

The laser shock peening technology for strengthening the surface of the metal material by high-energy pulse laser induced shock waves has a strong strengthening effect, and is widely researched and applied in recent years. The laser shock can improve the fatigue resistance of the material, but research is mainly focused on the laser shock of a circular light spot, the circular light spot is used in the traditional laser shock strengthening technology, and the research depth shows that in some cases, the residual compressive stress of the strengthened material at the central part of the light spot is lower than that of the periphery, and even becomes tensile stress. According to the forming reason of the residual stress hole summarized by the Fabbro, the convergence of sparse waves to the center of the light spot is the main reason for causing the residual stress hole. After the laser spot is converted into the square spot, the sparse waves are not converged at the center of the spot at the same time, and the phenomenon of residual stress holes is reduced. Compared with a circular light spot, the square light spot has the advantages of more uniform residual stress field, difficulty in generating stress holes, smooth surface of the workpiece after being strengthened, good quality and the like.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a light spot shaping device and a light spot shaping method for laser shock.

The purpose of the invention is realized by the following technical scheme:

a facula shaping device for laser shock, characteristics: be equipped with the microlens array system that is used for the facula plastic, be used for adjusting the plastic component, collimating mirror and the focusing mirror of facula size between income light mouth and light-emitting mouth in proper order, the microlens array system is arranged in on electronic slip table one, and is portable, plastic component contains the parallel beam expanding lens one, beam expanding lens two and the beam expanding lens three of arranging of equidistance in proper order, arranges electronic slip table two in, and is portable.

Further, in the above spot shaping device for laser shock, the microlens array system includes a microlens array and a focal plane, which are disposed between the light entrance hole and the light exit hole.

Further, in the above spot shaping device for laser shock, the microlens array is formed by arranging and combining microlenses with aperture of micron to hundred microns.

Further, in the above spot shaping device for laser shock, the microlenses of the microlens array are lenses with transmittances of 532nm and 1064nm of 99.5% or more.

Further, in the above spot shaping device for laser shock, the microlens array is a square microlens array, and converts the laser beam from a round spot to a square spot.

Further, in the spot shaping device for laser shock, the first beam expander, the second beam expander and the third beam expander are fixed on the bottom plate, the bottom plate is arranged on the second electric sliding table, the first beam expander is arranged on the left side of the second beam expander, and the third beam expander is arranged on the right side of the second beam expander; the distance between the central lines of the first beam expander and the second beam expander is 85mm, and the distance between the central lines of the third beam expander and the second beam expander is 85 mm; the distance between the bevel edges of the first beam expander and the second beam expander is 120mm, and the distance between the bevel edges of the third beam expander and the second beam expander is 120 mm; the focusing mirror is arranged on the electric sliding table III and can move.

The invention relates to a light spot shaping method for laser impact, wherein a laser beam enters from a light inlet, a round light spot is shaped into a square light spot with uniform energy distribution by a micro-lens array system, the size of the light spot is adjusted by controlling the switching of a beam expanding lens I, a beam expanding lens II and a beam expanding lens III of a shaping element by an electric sliding table II, the light beam is collimated by a collimating lens, and the light beam is output after being focused by a focusing lens; if the spot shaping is not needed, the electric sliding table I is used for controlling the micro-lens array system to move, so that the light beam does not pass through the micro-lens array system, the light beam directly passes through the shaping element to output a round spot, the light beam is collimated by the collimating lens and is output after being focused by the focusing lens, and the size of the spot is changed by driving the focusing lens through the electric sliding table III; the fast conversion of the light spot output by the laser between the round light spot and the square light spot is realized.

Furthermore, in the above spot shaping method for laser shock, the microlens array system includes a microlens array and a focal plane disposed between the light entrance hole and the light exit hole, when the incident light passes through the microlens array, the incident light is divided into a plurality of tiny sub-beams, the sub-beams are focused on the focal plane by the focusing lens, and then the square spots are output from the light exit hole.

Furthermore, in the spot shaping method for laser shock, the microlens array compresses the circular spots into square spots in two directions, the light intensity of the obtained square spots is flat-top distribution, and the fluctuation of the flat-top distribution of the light intensity is 98% ± 2%.

Furthermore, in the spot shaping method for laser shock, the first beam expander, the second beam expander and the third beam expander are arranged on the second electric sliding table and driven to move by the second electric sliding table, and the sizes of the spots are adjusted to be 3mm, 4mm and 5mm respectively.

Compared with the prior art, the invention has obvious advantages and beneficial effects, and is embodied in the following aspects:

the invention converts the round light spots into the square light spots by utilizing the micro-lens array, the light beam conversion efficiency is high, the light intensity distribution is uniform and flat, the peripheral boundaries of the light spots are sharp and have no ghost images, and the light spots are clear and regular in appearance. The device has the advantages of rapid conversion of the light spot output by the laser between the round light spot and the square light spot, simple structure and novel practical design.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1: the invention discloses a schematic diagram of a light path structure of a square light spot output form;

FIG. 2: a schematic structural diagram of a microlens array system;

FIG. 3: the invention is a schematic diagram of a light path structure in a circular light spot form;

FIG. 4: the position relationship of the three beam expanding lenses is shown schematically.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present invention, the directional terms and the sequence terms, etc. are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.

As shown in fig. 1 and 4, in the spot shaping device for laser shock, a micro lens array system 2 for spot shaping, a shaping element 4 for adjusting the size of a light spot, a collimating mirror 5 and a focusing mirror 6 are arranged between a light inlet 1 and a light outlet 8, the micro lens array system 2 is arranged on an electric sliding table one 3, and the electric sliding table one 3 can drive the micro lens array system 2 to move so as to enable the micro lens array system to enter or leave a light path; the shaping element comprises a first beam expander 13, a second beam expander 11 and a third beam expander 9 which are arranged in parallel in an equidistant staggered mode in sequence and are arranged on a bottom plate 12, the bottom plate 12 is arranged on a second electric sliding table 10, and the second electric sliding table 10 can drive the beam expanders to move; the mutual position relationship of the three beam expanders is shown in fig. 4, the distance between the central lines of the first beam expander 13 and the second beam expander 11 is 85mm, and the distance between the central lines of the third beam expander 9 and the second beam expander 11 is 85 mm; the distance between the first beam expander 13 and the second beam expander 11 is 120mm, and the distance between the third beam expander 9 and the second beam expander 11 is 120 mm; the focusing mirror 6 is arranged on the electric sliding table III 7 and can move.

The light beam is collimated by the collimating lens 5, the output laser converts the expanded beam light into parallel light through the collimating lens 5, and the parallel light is output after being focused by the focusing lens 6.

The focusing mirror 6 is arranged on the electric sliding table III 7 and can move; the focusing mirror 6 has two functions: firstly, the parallel light passing through the collimating lens 5 is focused, and secondly, when a round light spot is output, the size of the light spot is adjusted by moving the electric sliding table III 7.

As shown in fig. 2, the microlens array system 2 includes a microlens array 22 and a focal plane 23, which are disposed between a light entrance aperture 21 and a light exit aperture 24, and the microlens array 22 is formed by combining a number of microlenses with an aperture of several micrometers to several hundred micrometers in an arrangement order. The microlenses of the microlens array 22 are lenses having a transmittance of 532nm and 1064nm of 99.5% or more.

The microlens array 22 is a square microlens array, and converts the laser beam from a circular spot to a square spot. After passing through the microlens array 22, the incident light is divided into many small sub-beams, which are focused on the focal plane by the focusing lens, and finally the square light spot is output from the light outlet; the split sub-beams have small facula radius and high uniformity, so that the uniformity of the obtained focusing facula is improved.

The laser beam enters from the light inlet 1, the round light spot is shaped into a square light spot with uniform energy distribution by the micro-lens array system 2, when the incident light passes through the micro-lens array 22, the incident light is divided into a plurality of fine sub-beams, the sub-beams are focused on a focal plane 23 by a focusing lens, and then the square light spot is output from the light outlet 24; the micro lens array 22 compresses the round light spots into square light spots in two directions, the light intensity of the obtained square light spots is in flat-top distribution, the fluctuation of the light intensity flat-top distribution is 98% +/-2%, the light spot boundary is sharp, and no ghost image exists; the beam expander I13, the beam expander II 11 and the beam expander III 9 of the shaping element 4 are controlled through the electric sliding table II 10, the size of a light spot is adjusted, the electric sliding table II 10 drives the electric sliding table I to move, the size of the light spot can be adjusted to be 3mm, 4mm and 5mm respectively, a light beam is collimated through the collimating lens 5, and the light beam is focused by the focusing lens 6 and then is output.

As shown in fig. 3, if light spot shaping is not needed, the electric sliding table i 3 controls the movement of the micro lens array system 2, so that light beams do not pass through the micro lens array system 2, the light beams directly pass through the shaping element 4 to output round light spots, the light beams are collimated by the collimating lens 5, the light beams are output after being focused by the focusing lens 6, the size of the light spots is changed by driving the electric sliding table iii 7 to move the focusing lens 6, and the light spots output by the laser are rapidly converted between the round light spots and the square light spots.

In conclusion, the invention converts the round light spots into the square light spots by utilizing the micro-lens array, the light beam conversion efficiency is high, the light intensity distribution is uniform and flat, the peripheral boundaries of the light spots are sharp and have no ghost image, and the light spots are clear and regular in appearance. The device can quickly convert the light spot output by the laser between the round light spot and the square light spot, and has simple structure.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and shall be covered by the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.