Laser processing head and laser processing system for laser drilling

Abstract

The utility model relates to the technical field of laser processing, in particular to a laser processing head and a laser processing system for laser drilling. When in use, the laser processing head is fixed on a motor, the motor is used for driving the laser processing head to move up and down, and the laser processing head comprises a shell, a rotating mirror base and a third optical element; the shell is fixed on the motor, the lower surface of the shell is movably connected with a rotating mirror base, and the third optical element is arranged on the lower surface of the rotating mirror base and is eccentrically arranged with the rotating mirror base; the central axis of the shell and the rotating mirror base is the same as the optical axis of the laser beam. According to the utility model, various optical elements and an automatic control system are integrated, so that an efficient and high-precision laser processing system for punching processing can be obtained; according to the laser processing system, a series of optical elements including a refraction optical assembly, a diffraction optical element, a focusing lens, a rotating mirror base, a focusing objective lens and the like are utilized, and a modified area with a certain depth can be formed on a processed workpiece after laser beams are focused.

Description

Technical Field

[0001] The utility model relates to the technical field of laser processing, in particular to a laser processing head and a laser processing system for laser drilling. Background Art

[0002] Laser drilling technology has been widely used in modern industry, especially in the fields of electronic products, optical devices, etc. Due to its non-contact processing advantage, laser drilling has gradually become an important means in industrial processing. Traditional laser drilling technology usually uses a single focus for drilling. The disadvantage is that it is easy to cause micro cracks in the material, and subsequent chemical etching is easy to form elliptical holes, and the etching time is long. Utility Model Content

[0003] In order to solve the above problems, the purpose of the utility model is to provide a laser processing head and a laser processing system for laser drilling. In the utility model, high-speed and precise drilling is achieved during the laser drilling process by rotating the mirror seat.

[0004] Therefore, the present utility model proposes a laser drilling solution. Using this solution, the holes drilled in the material have a certain depth and are uniform, and the etching processing time is shorter, thereby achieving high-speed and precise laser drilling.

[0005] The purpose of the utility model can be achieved through the following technical solutions:

[0006] The first object of the utility model is to provide a laser processing head for laser drilling, which is fixed on a motor when in use, and the motor is used to drive the laser processing head to move up and down, and the laser processing head includes a housing, a rotating mirror seat and a third optical element;

[0007] The housing is fixed on the motor, a rotating mirror seat is movably connected to the lower surface of the housing, and the third optical element is arranged on the lower surface of the rotating mirror seat and is eccentrically arranged with the rotating mirror seat;

[0008] The central axis of the housing and the rotating mirror seat is the same as the optical axis of the laser beam.

[0009] When in use, the laser beam passes through the third optical element to form a long-focus deep-focus light spot;

[0010] The size and focal depth of the final focused light spot can be changed by adjusting the focal length and numerical aperture of the third optical element.

[0011] In one embodiment of the present invention, the distance between the central axis of the third optical element and the central axis of the rotating mirror base is 10 μm to 200 μm.

[0012] In one embodiment of the present invention, along the direction of travel of the laser beam, the inner cavity of the housing is provided with a first optical element and a second optical element in sequence and at intervals.

[0013] When in use, the laser beam passes through the first optical element to form a long-focus-depth Bessel laser beam, the long-focus-depth Bessel laser beam is initially focused by the second optical element, and finally enters the third optical element to form a long-focus-depth focused light spot;

[0014] The size and focal depth of the final focused light spot can be changed by adjusting the focal length of the second optical element and the focal length of the third optical element.

[0015] In one embodiment of the present invention, the first optical element is selected from one of a refractive optical element or a diffractive optical element (having a unique phase distribution design and capable of performing distribution modulation on an incident laser beam);

[0016] The second optical element is a focusing lens.

[0017] In one embodiment of the present invention, the refractive optical element is a conical lens, and the angle formed by the conical generatrix and the conical bottom surface of the conical lens is 0.5° to 20°.

[0018] In one embodiment of the present invention, the focal length of the second optical element is 35 mm to 300 mm.

[0019] In one embodiment of the present invention, the third optical element is a focusing objective lens.

[0020] In one embodiment of the present invention, the focal length of the third optical element is 4 mm to 25 mm;

[0021] The numerical aperture of the third optical element is 0.2 to 0.95.

[0022] The second object of the utility model is to provide a laser processing system, comprising the above-mentioned laser processing head.

[0023] In one embodiment of the utility model, when in use, it is arranged on an external stage and connected to an external computer to realize the processing of a workpiece placed on the surface of the stage. The laser processing system includes a laser emitter,

[0024] The laser emitter is used to emit a laser beam. Along the emission direction of the laser beam, a first reflector, a second reflector, a laser beam expander, a third reflector and a fourth reflector are sequentially arranged between the laser emitter and the laser processing head;

[0025] Wherein, the laser beam emitted by the laser emitter and the laser beam reflected by the second reflector have an angle, and are parallel to the laser beam reflected by the second reflector;

[0026] The central axis of the laser beam passing through the laser beam expander is the same as the optical axis of the laser beam reflected by the second reflector, has an angle with the laser beam reflected by the third reflector, and is perpendicular to the laser beam reflected by the fourth reflector;

[0027] The laser transmitter, motor and stage are all connected to the computer.

[0028] The third object of the utility model is to provide a processing method of a laser processing system, comprising the following steps:

[0029] A computer is used to control a laser transmitter to emit a laser beam, the laser beam is collimated to enter a first reflector, then collimated by the first reflector and the second reflector to enter a beam expander for laser beam expansion, then collimated to enter a third reflector, and finally collimated by the third reflector and the fourth reflector to enter a laser processing head, the laser beam passes through a first optical element, a second optical element and a third optical element, or the laser beam passes through the third optical element to form an eccentric focusing spot on a workpiece to be processed; the rotating mirror seat is controlled to rotate around an optical axis, and the focusing spot moves in a circle on the workpiece to be processed to form a circular modified area;

[0030] The computer controls the up and down movement of the motor and then controls the up and down movement of the laser processing head to form a circular modified area with a certain depth on the workpiece being processed;

[0031] The computer also adjusts the position of the workpiece being processed by controlling the movement of the stage.

[0032] Among them, the eccentricity is adjustable (the focusing spot is focused at the eccentric position), the laser beam passes through the third optical element, and forms an eccentric focusing spot at the workpiece to be processed. During the processing, the computer controls the rotating mirror seat to rotate around the optical axis, and the above-mentioned focusing spot performs circular motion accordingly. The use of the laser processing head of the utility model (including the first optical element and the second optical element) can directly obtain a circular modified area of ​​a certain depth (allowing the laser processing head to be moved up and down without using a motor); the use of the laser processing head of the utility model (excluding the first optical element and the second optical element) needs to be coordinated with the motor to move the focusing spot up and down to form a circular modified area with a certain depth.

[0033] If necessary, the processed workpiece can be subjected to subsequent processing steps such as chemical etching to eventually form a circular small hole on the processed workpiece.

[0034] Compared with the prior art, the utility model has the following beneficial effects:

[0035] (1) The utility model integrates a variety of optical elements and an automatic control system to obtain a laser processing system for efficient and high-precision drilling processing; the laser processing system utilizes a series of optical elements, including a refractive optical component, a diffractive optical element, a focusing lens, a rotating mirror mount, and a focusing objective lens, etc., which can focus the laser beam to form a modified area of ​​a certain depth on the workpiece being processed.

[0036] (2) The laser processing head of the utility model can be applied to ultrafast laser processing, such as high-speed drilling, and significantly improves the accuracy and efficiency of laser drilling. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a schematic diagram of the structure of the laser processing head described in Example 1;

[0038] Figure 2 is a schematic diagram of the structure of the rotating mirror base and the third optical element;

[0039] Figure 3 This is a schematic structural diagram of the laser processing head described in Example 2;

[0040] Figure 4 It is a structural schematic diagram of the laser processing system described in Example 3;

[0041] Figure 5 Schematic diagram of machining trajectory of the workpiece being machined (I);

[0042] Figure 6 Schematic diagram of the machining trajectory of the workpiece being machined (II)

[0043] Numbers in the figure: 1, housing; 2, first optical element; 3, second optical element; 4, rotating mirror seat; 5, third optical element; 6, motor; 100, laser processing head; 200, laser emitter; 300A, first reflector; 300B, second reflector; 300C, third reflector; 300D, fourth reflector; 400, laser beam expander; 500, laser beam; 600, workpiece to be processed; 700, stage; 800, computer; 900, focusing spot. DETAILED DESCRIPTION

[0044] The utility model is described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0047] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0048] In the following embodiments, unless otherwise specified, all components used are conventional commercially available components in the art, and they only need to be able to achieve corresponding functions.

[0049] Example 1

[0050] This embodiment provides a laser processing head for laser drilling, such as Figure 1 As shown, when in use, it is fixed on the motor 6, and the motor 6 is used to drive the laser processing head 100 to move up and down. The laser processing head 100 includes a shell 1, a rotating mirror seat 4 and a third optical element 5; wherein the shell 1 is fixed on the motor 6, and the rotating mirror seat 4 is movably connected to the lower surface of the shell 1. The third optical element 5 is arranged on the lower surface of the rotating mirror seat 4 and is eccentrically arranged with the rotating mirror seat 4 as shown in FIG. Figure 2 As shown;

[0051] Among them, the central axis of the shell 1 and the rotating mirror seat 4 is the same as the optical axis of the laser beam 500; when in use, the laser beam 500 passes through the third optical element 5 to form a long focal depth focused light spot 900; the focal length of the third optical element 5 and the numerical aperture of the third optical element 5 can be adjusted to change the size and focal depth of the final focused light spot 900.

[0052] Furthermore, the distance between the central axis of the third optical element 5 and the central axis of the rotating mirror base 4 is 10 μm to 200 μm, the third optical element 5 is a focusing objective lens, the focal length of the third optical element 5 is 4 mm to 25 mm, and the numerical aperture of the third optical element 5 is 0.2 to 0.95.

[0053] like Figure 2 As shown, the central axis of the rotating mirror base 414 is O1, the central axis of the third optical element 5 is O2, and the distance between O1 and O2 is defined as the eccentric distance d. The computer 800 controls the rotating mirror base 4 to rotate around the optical axis, driving the third optical element 5 to rotate, and the focused light spot 900 performs a circular motion accordingly, forming a circular modified area on the workpiece 600. The smaller the eccentric distance d, the smaller the radius of the circular modified area, and it will not be smaller than the size of the focused light spot 900.

[0054] Example 2

[0055] This embodiment provides a laser processing head for laser drilling, such as Figure 3 As shown, compared with the embodiment 1, the laser processing head 100 of this embodiment further includes a first optical element 2 and a second optical element 3 which are sequentially arranged in the inner cavity of the housing 1 along the direction of the laser beam 500 .

[0056] Furthermore, the first optical element 2 is selected from one of a refractive optical element or a diffractive optical element (having a unique phase distribution design and capable of performing distribution modulation on the incident laser beam 500); the second optical element 3 is a focusing lens.

[0057] Furthermore, the refractive optical element may be a conic lens, and the angle formed by the conical generatrix and the conical bottom surface of the conic lens is 0.5° to 20°; the focal length of the second optical element 3 is 35 mm to 300 mm.

[0058] Example 3

[0059] This embodiment provides a laser processing system, such as Figure 4 As shown, when in use, it is arranged on an external stage 700 and connected to an external computer 800, and is used to realize the processing of a workpiece 600 placed on the upper surface of the stage 700. The laser processing system includes a laser emitter 200 and the laser processing head 100 described in Example 1.

[0060] The laser emitter 200 is used to emit a laser beam 500. Along the emission direction of the laser beam 500, a first reflector 300A, a second reflector 300B, a laser beam expander 400, a third reflector 300C and a fourth reflector 300D are sequentially arranged between the laser emitter 200 and the laser processing head 100;

[0061] Among them, the laser beam 500 emitted by the laser emitter 200 has an angle with the laser beam 500 reflected by the second reflector 300B, and is parallel to the laser beam 500 reflected by the second reflector 300B; the central axis of the laser beam 500 passing through the laser beam expander 400 is the same as the optical axis of the laser beam 500 reflected by the second reflector 300B, has an angle with the laser beam 500 reflected by the third reflector 300C, and is perpendicular to the laser beam 500 reflected by the fourth reflector 300D; the laser emitter 200, the motor 6 and the stage 700 are all connected to the computer 800.

[0062] Example 4

[0063] This embodiment provides a processing method of a laser processing system (the laser processing system described in Embodiment 3), comprising the following steps:

[0064] The laser emitter 200 is controlled by a computer 800 to emit a laser beam 500. The laser beam 500 is collimated to enter the first reflector 300A, and then collimated by the first reflector 300A and the second reflector 300B to enter the beam expander for beam expansion, and then collimated to enter the third reflector 300C, and then collimated by the third reflector 300C and the fourth reflector 300D to enter the laser processing head 100. The laser beam 500 forms an eccentric focusing spot 900 on the workpiece 600 to be processed via the third optical element 5. The computer 800 is used to control the rotating mirror seat 4 to rotate around the optical axis, and the focusing spot 900 performs a circular motion on the workpiece 600 to form a circular modified area. At the same time, the up and down movement of the motor 6 is controlled by the computer 800 to control the up and down movement of the laser processing head 100 to form a circular modified area with a certain depth on the workpiece 600.

[0065] The computer 800 allows the movement of the stage 700 to be controlled so as to adjust the position of the workpiece 600 being processed.

[0066] Example 5

[0067] This embodiment provides a laser processing system, which is arranged on an external stage 700 and connected to an external computer 800 when in use, and is used to process a workpiece 600 placed on the upper surface of the stage 700. The laser processing system includes a laser emitter 200 and the laser processing head 100 described in Embodiment 2.

[0068] The laser emitter 200 is used to emit a laser beam 500. Along the emission direction of the laser beam 500, a first reflector 300A, a second reflector 300B, a laser beam expander 400, a third reflector 300C and a fourth reflector 300D are sequentially arranged between the laser emitter 200 and the laser processing head 100;

[0069] Among them, the laser beam 500 emitted by the laser emitter 200 has an angle with the laser beam 500 reflected by the second reflector 300B, and is parallel to the laser beam 500 reflected by the second reflector 300B; the central axis of the laser beam 500 passing through the laser beam expander 400 is the same as the optical axis of the laser beam 500 reflected by the second reflector 300B, has an angle with the laser beam 500 reflected by the third reflector 300C, and is perpendicular to the laser beam 500 reflected by the fourth reflector 300D; the laser emitter 200, the motor 6 and the stage 700 are all connected to the computer 800.

[0070] Example 6

[0071] This embodiment provides a processing method of a laser processing system (the laser processing system described in Embodiment 5), comprising the following steps:

[0072] The computer 800 is used to control the laser emitter 200 to emit a laser beam 500. The laser beam 500 is collimated and enters the first reflector 300A, and then collimated by the first reflector 300A and the second reflector 300B to enter the beam expander for beam expansion, and then collimated to enter the third reflector 300C, and then collimated by the third reflector 300C and the fourth reflector 300D to enter the laser processing head 100. The laser beam 500 passes through the first optical element 2 to form a Bessel laser beam 500. The Bessel laser beam is initially focused and adjusted through the second optical element 3 to adjust the divergence angle of the Bessel laser beam 500, and then forms an eccentric focusing spot 900 on the workpiece 600 through the third optical element 5. The computer 800 is used to control the rotating mirror seat 4 to rotate around the optical axis, and the focusing spot 900 makes a circular motion on the workpiece 600 to form a circular modified area.

[0073] The computer 800 allows the position of the workpiece 600 to be adjusted by controlling the movement of the stage 700 .

[0074] like Figure 5 and Figure 6As shown, C1 and C2 are the positions of the optical axis, l1 and l2 are the processing tracks formed by the focused light spot 900 when the rotating mirror base 4 rotates, wherein l1 is a PSO (position synchronized output) processing track generally used for glass, and l2 is a continuous processing track when the laser focus rotates the rotating mirror base 4. If necessary, a subsequent chemical etching process and other processing steps can be performed to finally form a circular small hole on the processed material.

[0075] In the above embodiment, the rotating mirror seat 4 and the motor 6 are automatically controlled by the computer 800 during the processing. The system in the computer 800 will automatically control the laser power, rotation speed, the front and rear and left and right displacements of the stage 700, and the height of the laser processing head 100 as needed, thereby increasing the punching processing speed, reducing the impact of the outside world on the punching displacement process, and improving the punching accuracy.

[0076] The above description of the embodiments is to facilitate the understanding and use of the utility model by those skilled in the art. It is obvious that those familiar with the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the utility model is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the interpretation of the utility model without departing from the scope of the utility model should be within the scope of protection of the utility model.

Claims

1. A laser processing head for laser drilling, which is fixed on a motor (6) when in use, and the motor (6) is used to drive the laser processing head (100) to move up and down, characterized in that: The laser processing head (100) comprises a housing (1), a rotating mirror seat (4) and a third optical element (5); The housing (1) is fixed on the motor (6); the lower surface of the housing (1) is movably connected to a rotating mirror seat (4); the third optical element (5) is arranged on the lower surface of the rotating mirror seat (4) and is eccentrically arranged with respect to the rotating mirror seat (4); The central axis of the housing (1) and the rotating mirror seat (4) is the same as the optical axis of the laser beam (500).

2. A laser processing head for laser drilling according to claim 1, characterized in that: The distance between the central axis of the third optical element (5) and the central axis of the rotating mirror seat (4) is 10 μm to 200 μm.

3. The laser processing head for laser drilling according to claim 1, characterized in that: Along the direction in which the laser beam (500) travels, the inner cavity of the housing (1) is provided with a first optical element (2) and a second optical element (3) arranged in sequence and at intervals.

4. A laser processing head for laser drilling according to claim 3, characterized in that: The first optical element (2) is selected from one of a refractive optical element and a diffractive optical element; The second optical element (3) is a focusing lens.

5. The laser processing head for laser drilling according to claim 4, characterized in that: The focal length of the second optical element (3) is 35 mm to 300 mm.

6. The laser processing head for laser drilling according to claim 1, characterized in that: The third optical element (5) is a focusing objective lens.

7. The laser processing head for laser drilling according to claim 6, characterized in that: The focal length of the third optical element (5) is 4 mm to 25 mm.

8. The laser processing head for laser drilling according to claim 6, characterized in that: The numerical aperture of the third optical element (5) is 0.2 to 0.

95.

9. A laser processing system, characterized in that: It comprises the laser processing head (100) as claimed in any one of claims 1 to 8.

10. A laser processing system according to claim 9, which is arranged on an external stage (700) and connected to an external computer (800) when in use, and is used to process a workpiece (600) placed on the upper surface of the stage (700), characterized in that: The laser processing system comprises a laser transmitter (200), The laser emitter (200) is used to emit a laser beam (500), and along the emission direction of the laser beam (500), a first reflector (300A), a second reflector (300B), a laser beam expander (400), a third reflector (300C) and a fourth reflector (300D) are sequentially arranged between the laser emitter (200) and the laser processing head (100); There is an angle between the laser beam (500) emitted by the laser emitter (200) and the laser beam (500) reflected by the second reflector (300B), and the laser beam (500) is parallel to the laser beam (500) reflected by the second reflector (300B); The central axis of the laser beam (500) passing through the laser beam expander (400) is the same as the optical axis of the laser beam (500) reflected by the second reflector (300B), is at an angle with the laser beam (500) reflected by the third reflector (300C), and is perpendicular to the laser beam (500) reflected by the fourth reflector (300D); The laser emitter (200), the motor (6) and the stage (700) are all connected to the computer (800).

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