Laser device

Abstract

The present application proposes a laser device comprising a beam shaper for shaping a pulsed laser beam, the beam shaper comprising a zeroth delay stage, a first delay stage, a second delay stage and a third delay stage, wherein, seen in projection along the propagation direction of the pulsed laser beam, the zeroth delay stage, the first delay stage, the second delay stage and the third delay stage are separated from one another with a four-equal-part cross dividing line, such that the zeroth delay stage, the first delay stage, the second delay stage and the third delay stage assume a quarter share of the pulsed laser beam impinging on the beam shaper, respectively. The present application is advantageous, inter alia, in that an approximately flat-top laser beam or an approximately M-shaped laser beam can be provided at low cost with a simple structure.

Description

Technical Field

[0001] This application relates to a laser device. Background Technology

[0002] Laser material processing uses laser beams to cut, weld, or modify materials with high precision. This technique minimizes heat-affected zones and is widely used in modern manufacturing for complex and efficient material processing. Typically, pulsed laser beams with high repetition rates are used.

[0003] The drawback is that generating a laser beam with the desired repetition rate and pulses is complex, inflexible, and limited by the characteristics of the laser source used. Utility Model Content

[0004] The purpose of this application is to provide a laser device, particularly enabling the provision of an approximately flat-top laser beam or an approximately M-shaped laser beam with a simple structure and low cost.

[0005] According to a first aspect of this application, a laser device is provided, characterized in that the laser device includes a beam shaper for shaping a pulsed laser beam having a pulse duration incident upon the beam shaper, the beam shaper including a zero-delay stage, a first delay stage, a second delay stage, and a third delay stage, the first delay stage being configured to cause a portion of a second pulsed laser beam incident on the first delay stage to have a delay greater than the pulse duration relative to a portion of the first pulsed laser beam incident on the zero-delay stage, the second delay stage being configured to cause a portion of a third pulsed laser beam incident on the second delay stage to have a delay greater than the pulse duration relative to a portion of the first pulsed laser beam incident on the zero-delay stage, the second delay stage being configured to cause a portion of the third pulsed laser beam incident on the second delay stage to have a delay greater than the pulse duration relative to a portion of the first pulsed laser beam incident on the zero-delay stage. The second pulse laser beam share incident on the first delay stage produces a delay greater than the pulse duration, and the third delay stage is configured to cause a fourth pulse laser beam share incident on the third delay stage to produce a delay greater than the pulse duration relative to the third pulse laser beam share incident on the second delay stage, wherein, viewed in projection along the propagation direction of the pulse laser beam, the zeroth delay stage, the first delay stage, the second delay stage, and the third delay stage are separated from each other by intersecting quarter-divided boundary lines, such that the zeroth delay stage, the first delay stage, the second delay stage, and the third delay stage each bear a quarter share of the pulse laser beam incident on the beam shaper.

[0006] According to an optional embodiment of this application, the beam shaper transmits the pulsed laser beam; the beam shaper includes a vacancy or a zeroth transmittance segment, the vacancy or the zeroth transmittance segment forming the zeroth delay stage; the beam shaper includes a first transmittance segment forming the first delay stage, a second transmittance segment forming the second delay stage, and a third transmittance segment forming the third delay stage; the first transmittance segment, the second transmittance segment, and the third transmittance segment have the same refractive index and the transmittance thickness increases sequentially, or, one of the first transmittance segment, the second transmittance segment, and the third transmittance segment has a different refractive index than the remaining two (the remaining two have the same refractive index), or, the first transmittance segment, the second transmittance segment, and the third transmittance segment all have different refractive indices; the first transmittance segment, the second transmittance segment, and the third transmittance segment have an incident surface for the pulsed laser beam to be incident perpendicularly and / or an exit surface for the pulsed laser beam to be emitted perpendicularly.

[0007] According to an optional embodiment of this application, the beam shaper includes a first transmission plate and a second transmission plate capable of transmitting the pulsed laser beam. The first transmission plate and the second transmission plate have overlapping portions. A first non-overlapping portion of the first transmission plate forms the first delay stage, a second non-overlapping portion of the second transmission plate forms the second delay stage, the overlapping portion forms the third delay stage, and a void not covered by the first and second transmission plates forms the zero delay stage. The first and / or the second transmission plate are glass plates. The second transmission plate has the same refractive index as the first transmission plate, and the thickness of the second transmission plate is greater than that of the first transmission plate. The beam shaper comprises the following dimensions: the first and / or the second transmission plate are rectangular or semi-circular; the first and second transmission plates are arranged perpendicularly to each other; in a plane perpendicular to the propagation direction of the pulsed laser beam, the first and second transmission plates are the same size and the overlapping portion is half the size of the first and second transmission plates; the first and second transmission plates are fixed relative to each other; the surfaces of the first and / or the second transmission plates are provided with an anti-reflective coating; the thickness of the first and / or the second transmission plates is in the range of 0.1 mm to 60 mm; the beam shaper includes a frame for holding the first and second transmission plates.

[0008] According to an optional embodiment of this application, the first transmission plate and / or the second transmission plate are ultraviolet fused silica glass plates.

[0009] According to an optional embodiment of this application, the beam shaper includes a first optical wedge and a second optical wedge capable of transmitting the pulsed laser beam. The first optical wedge and the second optical wedge have overlapping portions. A first non-overlapping portion of the first optical wedge forms the first delay stage. A second non-overlapping portion of the second optical wedge forms the second delay stage. The overlapping portions form the third delay stage. A gap not covered by the first optical wedge and the second optical wedge forms the zero delay stage.

[0010] According to an optional embodiment of this application, the beam shaper reflects the pulsed laser beam; the beam shaper includes a zero-th reflection surface, a first reflection surface, a second reflection surface, and a third reflection surface, the zero-th reflection surface, the first reflection surface, the second reflection surface, and the third reflection surface being spaced apart from each other to correspondingly form the zero-th delay stage, the first delay stage, the second delay stage, and the third delay stage; the zero-th reflection surface, the first reflection surface, the second reflection surface, and the third reflection surface form a stepped structure.

[0011] According to an optional embodiment of this application, the cross-boundary line is a cross-shaped boundary line or a cross-boundary curve; and / or, the laser device is configured to allow the optical axis of the pulsed laser beam to pass through the intersection of the cross-boundary line; and / or, the zeroth delay stage is opposite to the third delay stage and the first delay stage is opposite to the second delay stage; and / or, the third delay stage is configured to allow the delay of the fourth pulsed laser beam fraction incident on the third delay stage relative to the first pulsed laser beam fraction incident on the zeroth delay stage to be below the pulse interval time of the pulsed laser beam.

[0012] According to an optional embodiment of this application, the delay generated by the first delay stage, the second delay stage, and / or the third delay stage is equal to the pulse duration; or, the delay generated by the first delay stage, the second delay stage, and / or the third delay stage is at most 10% longer than the pulse duration.

[0013] According to an optional embodiment of this application, the pulsed laser beam is an ultrashort pulsed laser beam; and / or, the pulsed laser beam has a pulse duration of less than 20 ps; and / or, the average wavelength of the pulsed laser beam is in the range of 200 nm to 3000 nm; and / or, the beam diameter of the pulsed laser beam is in the range of 5 mm to 100 mm; and / or, the power of the pulsed laser beam is less than 1 GW.

[0014] According to an optional embodiment of this application, the laser device is a laser device for laser ablation, laser erosion, or laser cleaning; and / or, the laser device includes a focusing device disposed downstream of the beam shaper; and / or, the laser device includes a pulsed laser source disposed upstream of the beam shaper to generate a pulsed laser beam directed onto the beam shaper; and / or, the laser device includes a scanning galvanometer disposed downstream of the beam shaper; and / or, the laser device includes a beam monitoring module; and / or, the laser device includes a beam stabilization module; and / or, the laser device includes a motion mechanism for the beam shaper, the motion mechanism being configured to move the beam shaper transversely to the propagation direction of the pulsed laser beam.

[0015] At least in some embodiments, the positive effects of this application are: simple and robust structure; composed of standard optical elements, easy to manufacture and inexpensive; virtually no dispersion; compact size, easily integrated into most optical systems; adjustable size to accommodate larger original beams without significantly increasing cost; high energy efficiency, with most energy concentrated in the flat top region and minimal energy loss; adjustable beam shape; the intensity distribution of the quasi-flat top beam can be changed by adjusting the original beam diameter, focal length, and working distance; and it facilitates the generation of uniform heat distribution. Attached Figure Description

[0016] The principles, features, and advantages of this application will be better understood below with reference to the accompanying drawings. The drawings include:

[0017] Figure 1 An example of the laser device of this application is illustrated schematically.

[0018] Figure 2 An example of the beam shaper of this application is illustrated schematically.

[0019] Figure 3 An example of a focal point formed after a pulsed laser beam passes through a beam shaper and a focusing device is illustrated.

[0020] Figure 4 An example of an output laser beam formed by a laser device is illustrated schematically.

[0021] Figure 5 This illustration shows another example of an output laser beam formed by a laser device.

[0022] Figure 6 Another example of a beam shaper is illustrated schematically.

[0023] Figure 7 Another example of a beam shaper is illustrated in a 3D diagram.

[0024] Figure 8 Another example of a beam shaper is illustrated in a 3D diagram.

[0025] Figure 9 Another example of a beam shaper is illustrated schematically.

[0026] Figure 10 Another example of a beam shaper is illustrated schematically.

[0027] Figure 11 Another example of a beam shaper is illustrated schematically. Detailed Implementation

[0028] To make the technical problems to be solved, the technical solutions, and the beneficial technical effects of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and several exemplary embodiments. It should be understood that the specific embodiments described herein are only for explaining this application and are not intended to limit the scope of protection of this application.

[0029] Figure 1 An example of the laser device of this application is illustrated schematically. The laser device may be used for laser ablation, laser erosion, or laser cleaning.

[0030] like Figure 1 As shown, the laser device includes at least a beam shaper 1. The beam shaper 1 is used to guide the pulsed laser beam 8 (participating in...) that is directed onto the beam shaper 1. Figure 2 The pulsed laser beam 8 is shaped. It has a pulse duration or pulse width. The pulsed laser beam 8 can be an ultrashort pulse laser beam. The pulsed laser beam 8 can have a pulse duration of less than 20 ps. The average wavelength of the pulsed laser beam 8 can be in the range of 200 nm to 3000 nm, particularly in the range of 200 nm to 1030 nm. The beam diameter of the pulsed laser beam 8 can be in the range of 5 mm to 100 mm, particularly in the range of 2.5 mm to 50 mm. The power of the pulsed laser beam 8 can be below 1 GW, particularly below 100 MW.

[0031] In addition to the beam shaper 1, see also Figure 1 The laser device may further include at least one of the following:

[0032] A pulsed laser source 21 is arranged upstream of the beam shaper 1 to generate a pulsed laser beam 8 that is directed to the beam shaper 1;

[0033] A scanning mirror 22 is arranged downstream of the beam shaper 1, and the scanning mirror 22 is used to move the pulsed laser beam 8 on the workpiece 26.

[0034] A focusing device 20 is arranged downstream of the beam shaper 1, and the focusing device 20 is particularly arranged downstream of the scanning galvanometer 22;

[0035] Beam monitoring module 23 is used to monitor the status of pulsed laser beam 8;

[0036] Beam stabilization module 24, used to center the pulsed laser beam 8; and

[0037] The motion mechanism 25 is used to move the beam shaper 1 laterally to the propagation direction of the pulsed laser beam 8.

[0038] Alternatively or additionally, the motion mechanism 25 may be used to move the beam shaper 1 along the propagation direction and / or rotate the beam shaper 1.

[0039] Figure 2 An example of the beam shaper 1 of this application is schematically shown. Figure 2 In the diagram, an example of a pulsed laser beam 8 incident on the beam shaper 1 is schematically shown as a dashed circle. However, the pulsed laser beam 8 is not limited to a circle.

[0040] like Figure 2 As shown, the beam shaper 1 includes a zero-delay stage 10, a first delay stage 11, a second delay stage 12, and a third delay stage 13. The first delay stage 11 is configured to cause a second pulse laser beam fraction 82 incident on the first delay stage 11 to have a delay of more than or equal to the pulse duration relative to the first pulse laser beam fraction 81 incident on the zero-delay stage 10. The second delay stage 12 is configured to cause a third pulse laser beam fraction 83 incident on the second delay stage 12 to have a delay of more than or equal to the pulse duration relative to the second pulse laser beam fraction 82 incident on the first delay stage 11. The third delay stage 13 is configured to cause a delay of more than the pulse duration relative to the third pulse laser beam share 83 incident on the second delay stage 12, wherein, viewed in projection along the propagation direction of the pulse laser beam 8, the zero delay stage 10, the first delay stage 11, the second delay stage 12 and the third delay stage 13 are separated from each other by a quarter-divided dividing line 6, such that the zero delay stage 10, the first delay stage 11, the second delay stage 12 and the third delay stage 13 each bear a quarter share of the pulse laser beam 8 incident on the beam shaper 1.

[0041] Figure 3An example of a focal point 7 formed after the pulsed laser beam 8 passes through the beam shaper 1 and the focusing device 20 is illustrated schematically. The distance between the focal points 7 is shown exaggeratedly here.

[0042] See Figure 3 Because the resulting delay exceeds the pulse duration, the portions of the pulsed laser beam 8 that strike the four delay stages are staggered in time through the delay stages, thus preventing interference at the output and generating four focal points 7. Overall, the four focal points 7 combine to form a significantly larger focal point 7.

[0043] Figure 4 An example of an output laser beam formed by a laser device is illustrated schematically.

[0044] Figure 5 This illustration shows another example of an output laser beam formed by a laser device.

[0045] Here, the focal plane is at 167 mm. Figure 4 The diagram shows the profile of the laser beam output at 167.28 mm, which approximates a flat-top laser beam. Figure 5 The figure shows the profile of the laser beam output at 167.40 mm, which approximates an M-type laser beam.

[0046] Therefore, the solution of this application can form an output laser beam with an energy distribution between the flat-top laser beam and the M-type laser beam, which is particularly advantageous in terms of uniform heat distribution.

[0047] According to an exemplary embodiment of this application, see Figure 2 The laser device is configured to allow the optical axis of the pulsed laser beam 8 to pass through the intersection point 60 of the dividing line 6.

[0048] According to an exemplary embodiment of this application, see Figure 2 The third delay stage 13 is configured such that the delay of the fourth pulse laser beam fraction 84 incident on the third delay stage 13 relative to the first pulse laser beam fraction 81 incident on the zero delay stage 10 is less than (or equal to) the pulse interval time of the pulse laser beam 8. Thus, the subsequent pulse laser beam 8 does not interfere with the preceding pulse laser beam 8, and in particular, does not interfere with the fourth pulse laser beam fraction 84 of the preceding pulse laser beam 8.

[0049] According to an exemplary embodiment of this application, the delay generated by the first delay stage 11, the second delay stage 12, and / or the third delay stage 13 is equal to the pulse duration. Alternatively, the delay generated by the first delay stage 11, the second delay stage 12, and / or the third delay stage 13 is at most 10% longer than the pulse duration.

[0050] Here, specifically within the pulsed laser beam 8, the four delay stages are separated from each other by four intersecting boundary lines 6, so that each stage takes up a quarter of the pulsed laser beam 8. Outside the pulsed laser beam 8, the boundary lines between the four delay stages are not mandatory.

[0051] Figure 6 Another example of beam shaper 1 is illustrated schematically. (e.g.) Figure 6 As shown, outside the diameter range of the pulsed laser beam 8, the boundary lines between the four delay stages can be irregular, or in other words, the configuration of the beam shaper 1 in the region outside the range of the pulsed laser beam 8 can be arbitrary.

[0052] Figure 7 Another example of beam shaper 1 is shown schematically in a three-dimensional view.

[0053] According to an exemplary embodiment of this application, see Figure 7 The beam shaper 1 transmits the pulsed laser beam 8. Here, delay is generated based on transmission. In the case of transmission, the focusing device 20 is, for example, a focusing lens.

[0054] According to an exemplary embodiment of this application, see Figure 2 or Figure 7 The beam shaper 1 includes a vacancy 30 that forms the zero-delay stage 10. This allows for the simple and low-cost formation of the zero-delay stage 10. Here, in the zero-delay stage 10, the pulsed laser beam 8 is transmitted, for example, through air.

[0055] Alternatively, it may be conceivable that the beam shaper 1 includes a zeroth transmittance segment forming the zeroth delay stage 10. The transmittance is understood herein as a solid-state transmittance. The zeroth transmittance is, for example, glass.

[0056] According to an exemplary embodiment of this application, see Figure 7 The beam shaper 1 includes a first transmissive segment 31 forming the first delay stage 11, a second transmissive segment 32 forming the second delay stage 12, and a third transmissive segment 33 forming the third delay stage 13. The transmissive segments can be independent of each other or integrated with each other.

[0057] See Figure 7 When the first transmission segment 31, the second transmission segment 32, and the third transmission segment 33 are made of the same material or have the same refractive index, delay is generated, for example, by their different transmission segment thicknesses. Here, the transmission segment thicknesses of the first transmission segment 31 to the third transmission segment 33 increase sequentially. The transmission segment thickness specifically refers to the thickness along the propagation direction of the pulsed laser beam 8.

[0058] Furthermore, by way of example, in the case where a transmissive segment includes a cavity along the propagation direction, the thickness of the transmissive should be understood as the thickness excluding the cavity.

[0059] Instead of varying thicknesses, it is also conceivable that the various transmissive segments have different refractive indices to generate delay. Clearly, with different refractive indices, the individual transmissive segments can have the same or different transmissive thicknesses.

[0060] According to an exemplary embodiment of this application, such as Figure 7 As shown, the zeroth delay stage 10 is opposite to the third delay stage 13, and the first delay stage 11 is opposite to the second delay stage 12. However, alternatively, a different relative positional relationship between the four delay stages can be conceived.

[0061] According to an exemplary embodiment of this application, see Figure 7 The first transmissive segment 31, the second transmissive segment 32 and the third transmissive segment 33 have an incident surface 34 for the pulsed laser beam 8 to be incident perpendicularly and / or an exit surface 35 for the pulsed laser beam 8 to be emitted perpendicularly.

[0062] Figure 8 Another example of the beam shaper 1 is schematically shown in a perspective view. Here, the pulsed laser beam 8 is indicated by a downward arrow. Those skilled in the art will recognize that the effect is consistent when the pulsed laser beam 8 passes through the beam shaper 1 from bottom to top.

[0063] According to an exemplary embodiment of this application, such as Figure 8As shown, the beam shaper 1 includes a first transmission plate 41 and a second transmission plate 42 capable of transmitting the pulsed laser beam 8. The first transmission plate 41 and the second transmission plate 42 may have overlapping portions 43. It is conceivable that the first non-overlapping portion 410 of the first transmission plate 41 forms the first delay stage 11, the second non-overlapping portion 420 of the second transmission plate 42 forms the second delay stage 12, the overlapping portion 43 forms the third delay stage 13, and the void portion 30 not covered by the first transmission plate 41 and the second transmission plate 42 forms the zero delay stage 10. This allows the beam shaper 1 to be manufactured simply and at low cost. The overlapping portion 43 forming the third delay stage 13 should be understood as the first overlapping portion 411 of the first transmission plate 41 and the second overlapping portion 422 of the second transmission plate 42 combining to form the third delay stage 13.

[0064] The thickness of the first transmission plate 41 and / or the second transmission plate 42 may be in the range of 0.1 mm to 60 mm, for example.

[0065] exist Figure 8 In this example, the first transmission plate 41 and the second transmission plate 42 are attached to each other. It is conceivable that the first transmission plate 41 and the second transmission plate 42 are glued together. However, it is also possible that the first transmission plate 41 and the second transmission plate 42 are spaced apart. Here, the first transmission plate 41 and the second transmission plate 42 can be fixed relative to each other, for example, by a frame 14.

[0066] According to an exemplary embodiment of this application, the first transmission plate 41 and / or the second transmission plate 42 are glass plates, especially ultraviolet fused silica glass plates.

[0067] According to an exemplary embodiment of this application, see Figure 8 The second transmission plate 42 has the same refractive index as the first transmission plate 41, and the thickness of the second transmission plate 42 is greater than the thickness of the first transmission plate 41. It is conceivable that the thickness of the first transmission plate 41 is chosen such that the resulting delay is exactly equal to the pulse duration. The thickness of the second transmission plate 42 can be twice the thickness of the first transmission plate 41.

[0068] According to an exemplary embodiment of this application, see Figure 8 The first transmission plate 41 and / or the second transmission plate 42 are rectangular.

[0069] Figure 9 Another example of beam shaper 1 is illustrated schematically. (e.g.) Figure 9As shown, the first transmission plate 41 and / or the second transmission plate 42 can also be semicircles. Here, the first transmission plate 41 is a left semicircle, and the second transmission plate 42 is a lower semicircle.

[0070] According to an exemplary embodiment of this application, such as Figure 8 or Figure 9 As shown, the first transmission plate 41 and the second transmission plate 42 are arranged perpendicular to each other. This is particularly understood to mean that the length direction of the first transmission plate 41 is perpendicular to the length direction of the second transmission plate 42.

[0071] According to an exemplary embodiment of this application, such as Figure 8 or Figure 9 As shown, in a plane perpendicular to the propagation direction of the pulsed laser beam 8, the first transmission plate 41 and the second transmission plate 42 are of equal size, and the overlapping portion 43 is half the size of the first transmission plate 41 and the second transmission plate 42. This results in an overall regular configuration of the beam shaper 1.

[0072] According to an exemplary embodiment of this application, such as Figure 2 or Figure 9 As shown, the beam shaper 1 includes a frame 14 for holding the first transmission plate 41 and the second transmission plate 42.

[0073] According to an exemplary embodiment of this application, the surfaces of the first transmissive plate 41 and / or the second transmissive plate 42 are provided with an anti-reflective coating.

[0074] According to an exemplary embodiment of this application, the beam shaper 1 includes a first optical wedge and a second optical wedge capable of transmitting the pulsed laser beam 8. Further design of the first and second optical wedges can be referenced to the first and second transmission plates, and will not be repeated here.

[0075] Figure 10 Another example of beam shaper 1 is illustrated schematically.

[0076] According to an exemplary embodiment of this application, such as Figure 10 As shown, the beam shaper 1 reflects the pulsed laser beam 8. In the case of reflection, the focusing device 20 may be, for example, a concave mirror.

[0077] Here, the beam shaper 1 may, for example, include a zero-reflection surface 50, a first reflection surface 51, a second reflection surface 52, and a third reflection surface 53. The zero-reflection surface 50, the first reflection surface 51, the second reflection surface 52, and the third reflection surface 53 may be spaced apart from each other to correspondingly form the zero-delay stage 10, the first delay stage 11, the second delay stage 12, and the third delay stage 13. Figure 10 As shown, the zeroth reflective surface 50, the first reflective surface 51, the second reflective surface 52, and the third reflective surface 53 can form a stepped structure. Here, exemplarily, the zeroth delay stage 10 is opposite to the second delay stage 12 and the first delay stage 11 is opposite to the third delay stage 13.

[0078] In the previous example, especially within the range of the pulsed laser beam 8, the intersecting boundary line 6 is a cross-shaped boundary line.

[0079] Figure 11 Another example of beam shaper 1 is schematically shown. Instead of a crosshair dividing line, as... Figure 11 As shown, the intersecting boundary line 6 can also be an intersecting boundary curve. Alternatively, the intersecting boundary line 6 may include both straight and curved portions.

[0080] exist Figure 2 , Figure 6 , Figure 9 and Figure 11 In the figure, the propagation direction of the pulsed laser beam 8 can be understood as along a direction perpendicular to the plane of the figure.

[0081] The dimensions, quantity, position, shape, and interrelationships of the elements in the accompanying drawings should be understood as examples, not as absolute limitations of this application. Those skilled in the art can also conceive of simple variations in the dimensions, quantity, position, shape, and interrelationships of these elements without departing from the scope of protection of this application.

[0082] Provided that it is permissible in principle, each of the cited features can be considered as an individual feature and can be combined with any other feature in any form without departing from the scope of protection of this application. If it is permissible in principle, even if not explicitly stated, a feature described for one embodiment should be considered as being arbitrarily applicable to other embodiments.

[0083] Expressions such as “quarters” should be understood within a tolerance range, especially 10%.

[0084] The ordinal numbers such as "first," "second," and "third" in this specification are primarily used to avoid confusion among the constituent elements and should not be construed as having any other limiting effect.

[0085] Although specific embodiments of this application are described in detail herein, they are given for illustrative purposes only and should not be construed as limiting the scope of this application. Various substitutions, modifications, and alterations can be conceived without departing from the spirit and scope of this application.

[0086] List of reference numerals

[0087] 1 Beam Shaper

[0088] 10. Zero-delay level

[0089] 11 First Delay Stage

[0090] 12 Second Delay Stage

[0091] 13 Third Delay Stage

[0092] 14 frames

[0093] 20 focusing devices

[0094] 21-pulse laser source

[0095] 22 scanning galvanometers

[0096] 23-beam monitoring module

[0097] 24-beam stabilization module

[0098] 25 sports organizations

[0099] 26 workpieces

[0100] 30 vacant departments

[0101] 31 First Transmitter Segment

[0102] 32 Second Transmitter Segment

[0103] 33 Third Transmitter Segment

[0104] 34 Incident Surface

[0105] 35 Exit Surface

[0106] 41 First transmission plate

[0107] 410 First non-overlapping part

[0108] 411 First overlapping part

[0109] 42 Second transmission plate

[0110] 420 Second non-overlapping part

[0111] 422 Second overlapping part

[0112] 43 overlapping parts

[0113] 50 Zeroth Reflection Surface

[0114] 51 First reflecting surface

[0115] 52 Second Reflecting Surface

[0116] 53 Third Reflecting Surface

[0117] 6 Intersecting Boundary Lines

[0118] 60 intersections

[0119] 7 Focuses

[0120] 8-pulse laser beam

[0121] 81% of the first pulse laser beam

[0122] 82% of the second pulse laser beam

[0123] 83% of the third pulse laser beam

[0124] 84% of the fourth pulse laser beam

Claims

1. A laser device, characterized in that, The laser device includes a beam shaper (1) for shaping a pulsed laser beam (8) having a pulse duration incident on the beam shaper (1). The beam shaper (1) includes a zero-delay stage (10), a first delay stage (11), a second delay stage (12), and a third delay stage (13). The first delay stage (11) is configured to cause a second pulsed laser beam fraction (82) incident on the first delay stage (11) to have a delay of more than the pulse duration relative to the first pulsed laser beam fraction (81) incident on the zero-delay stage (10). The second delay stage (12) is configured to cause a third pulsed laser beam fraction (83) incident on the second delay stage (12) to have a delay of more than the pulse duration relative to the second pulsed laser beam fraction (81) incident on the first delay stage (11). The pulse laser beam share (82) produces a delay greater than the pulse duration, and the third delay stage (13) is configured to cause the fourth pulse laser beam share (84) incident on the third delay stage (13) to produce a delay greater than the pulse duration relative to the third pulse laser beam share (83) incident on the second delay stage (12), wherein, viewed in projection along the propagation direction of the pulse laser beam (8), the zero delay stage (10), the first delay stage (11), the second delay stage (12) and the third delay stage (13) are separated from each other by a quarter-divided dividing line (6) such that the zero delay stage (10), the first delay stage (11), the second delay stage (12) and the third delay stage (13) each bear a quarter share of the pulse laser beam (8) incident on the beam shaper (1).

2. The laser device according to claim 1, characterized in that, The beam shaper (1) transmits the pulsed laser beam (8); The beam shaper (1) includes a vacancy (30) or a zeroth transmission segment, the vacancy (30) or the zeroth transmission segment forming the zeroth delay stage (10); The beam shaper (1) includes a first transmissive segment (31) forming the first delay stage (11), a second transmissive segment (32) forming the second delay stage (12), and a third transmissive segment (33) forming the third delay stage (13); The first transmission body segment (31), the second transmission body segment (32), and the third transmission body segment (33) have the same refractive index and the thickness of the transmission body increases sequentially; or, one of the first transmission body segment (31), the second transmission body segment (32), and the third transmission body segment (33) has a different refractive index than the other two; or, the first transmission body segment (31), the second transmission body segment (32), and the third transmission body segment (33) all have different refractive indices. The first transmissive segment (31), the second transmissive segment (32) and the third transmissive segment (33) have an incident surface (34) for the pulsed laser beam (8) to be incident perpendicularly and / or an exit surface (35) for the pulsed laser beam (8) to be emitted perpendicularly.

3. The laser device according to claim 1, characterized in that, The beam shaper (1) includes a first transmission plate (41) and a second transmission plate (42) capable of transmitting the pulsed laser beam (8). The first transmission plate (41) and the second transmission plate (42) have overlapping portions (43). The first non-overlapping portion (410) of the first transmission plate (41) forms the first delay stage (11). The second non-overlapping portion (420) of the second transmission plate (42) forms the second delay stage (12). The overlapping portion (43) forms the third delay stage (13). The vacancy portion (30) not covered by the first transmission plate (41) and the second transmission plate (42) forms the zero delay stage (10). The first transmission plate (41) and / or the second transmission plate (42) are glass plates; The second transmission plate (42) has the same refractive index as the first transmission plate (41), and the thickness of the second transmission plate (42) is greater than the thickness of the first transmission plate (41). The first transmission plate (41) and / or the second transmission plate (42) are rectangular or semi-circular; The first transmission plate (41) and the second transmission plate (42) are arranged perpendicular to each other; In a plane perpendicular to the propagation direction of the pulsed laser beam (8), the first transmission plate (41) and the second transmission plate (42) are the same size and the overlapping portion (43) is half the size of the first transmission plate (41) and the second transmission plate (42). The first transmission plate (41) and the second transmission plate (42) are fixed relative to each other; The surfaces of the first transmissive plate (41) and / or the second transmissive plate (42) are provided with an anti-reflective coating; The thickness of the first transmission plate (41) and / or the second transmission plate (42) is in the range of 0.1 mm to 60 mm; The beam shaper (1) includes a frame (14) for holding the first transmission plate (41) and the second transmission plate (42).

4. The laser device according to claim 3, characterized in that, The first transmission plate (41) and / or the second transmission plate (42) are ultraviolet fused silica glass plates.

5. The laser device according to claim 1, characterized in that, The beam shaper (1) includes a first optical wedge and a second optical wedge that can transmit the pulsed laser beam (8). The first optical wedge and the second optical wedge have overlapping portions. The first non-overlapping portion of the first optical wedge forms the first delay stage. The second non-overlapping portion of the second optical wedge forms the second delay stage. The overlapping portion forms the third delay stage. The vacancy portion not covered by the first optical wedge and the second optical wedge forms the zero delay stage.

6. The laser device according to claim 1, characterized in that, The beam shaper (1) reflects the pulsed laser beam (8); The beam shaper (1) includes a zero-th reflection surface (50), a first reflection surface (51), a second reflection surface (52), and a third reflection surface (53), which are spaced apart from each other to form the zero-th delay stage (10), the first delay stage (11), the second delay stage (12), and the third delay stage (13) respectively. The zeroth reflective surface (50), the first reflective surface (51), the second reflective surface (52), and the third reflective surface (53) form a stepped structure.

7. The laser device according to any one of claims 1 to 6, characterized in that, The intersecting boundary line (6) is a cross-shaped boundary line or an intersecting boundary curve; and / or The laser device is configured to allow the optical axis of the pulsed laser beam (8) to pass through the intersection (60) of the dividing line (6); and / or The zeroth delay stage (10) is opposite to the third delay stage (13), and the first delay stage (11) is opposite to the second delay stage (12); and / or The third delay stage (13) is configured to cause the delay of the fourth pulse laser beam share (84) incident on the third delay stage (13) relative to the first pulse laser beam share (81) incident on the zero delay stage (10) to be below the pulse interval time of the pulse laser beam (8).

8. The laser device according to any one of claims 1 to 6, characterized in that, The delay produced by the first delay stage (11), the second delay stage (12), and / or the third delay stage (13) is equal to the pulse duration; or The delay produced by the first delay stage (11), the second delay stage (12) and / or the third delay stage (13) is at most 10% longer than the pulse duration.

9. The laser device according to any one of claims 1 to 6, characterized in that, The pulsed laser beam (8) is an ultrashort pulse laser beam; and / or The pulsed laser beam (8) has a pulse duration of less than 20 ps; and / or The average wavelength of the pulsed laser beam (8) is in the range of 200 nm to 3000 nm; and / or The beam diameter of the pulsed laser beam (8) is in the range of 5 mm to 100 mm; and / or The power of the pulsed laser beam (8) is below 1 GW.

10. The laser device according to any one of claims 1 to 6, characterized in that, The laser device is used for laser ablation, laser erosion, or laser cleaning; and / or The laser device includes a focusing device (20) disposed downstream of the beam shaper (1); and / or The laser device includes a pulsed laser source (21) disposed upstream of the beam shaper (1) to generate a pulsed laser beam (8) directed to the beam shaper (1); and / or The laser device includes a scanning galvanometer (22) disposed downstream of the beam shaper (1); and / or The laser device includes a beam monitoring module (23); and / or The laser device includes a beam stabilization module (24); and / or The laser device includes a motion mechanism (25) for the beam shaper (1), the motion mechanism (25) being configured to move the beam shaper (1) transverse to the propagation direction of the pulsed laser beam (8).

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