Flat-top laser flat-top position determination method and system

Abstract

The application relates to a flat-top laser flat-top position determination method and system, the method comprising: making flat-top laser generated by the laser generating device sequentially pass through a diaphragm hole of a diaphragm and a lens, and making the diaphragm hole of the diaphragm be imaged on an imaging device; adjusting a first interval between the diaphragm hole of the diaphragm and the lens to a preset value; adjusting a second interval between the lens and the imaging device, so that the imaging of the diaphragm hole meets a target definition, and the position of the imaging of the diaphragm hole corresponding to the imaging device is taken as the flat-top position of the flat-top laser. The technical scheme can improve the efficiency of determining the flat-top position of the flat-top laser.

Description

Technical Field

[0001] This invention relates to the field of laser processing technology, and in particular to a method and system for determining the flat-top position of a flat-top laser. Background Technology

[0002] Typically, laser beams generated by lasers are Gaussian beams. The energy distribution of a Gaussian beam across its propagation path follows a Gaussian function, meaning the energy is highest at the center and gradually decreases towards the edges. This characteristic of Gaussian beams prevents their direct application in certain laser drilling scenarios, such as laser drilling of PCB boards. Direct application would result in lower energy at the edges, failing to achieve the desired effect, while the center would have excessively high energy, leading to energy waste. In such cases, it is usually necessary to convert the Gaussian laser into a flat-top laser. Flat-top lasers have a relatively uniform energy distribution, which meets the requirements for PCB drilling.

[0003] Existing technologies exist that convert laser light from a laser source into a flat-top laser through a specific optical path. However, the laser light generated by the laser source attenuates rapidly and has a short propagation distance after passing through the specific optical path. A unique flat-top position exists along its propagation path, defined as the cross-section where the laser energy distribution is most uniform. Typically, the location of this flat-top position needs to be determined first before laser drilling can be performed. However, determining the flat-top position using existing technologies is cumbersome and inefficient. Summary of the Invention

[0004] This invention provides a method and system for determining the flat-top position of a flat-top laser, which can quickly determine the position of the flat-top laser and improve the debugging efficiency before laser processing.

[0005] In a first aspect, this application provides a method for determining the flat-top position of a flat-top laser, the method being applied to a flat-top laser flat-top position determination system, the flat-top laser flat-top position determination system comprising: a laser generating device, an aperture, a lens, and an imaging device, wherein the laser generating device is used to generate a flat-top laser, and the method comprises: The flat-top laser generated by the laser generating device passes sequentially through the aperture of the aperture and the lens, and the aperture of the aperture is imaged on the imaging device. Adjust the first distance between the aperture of the aperture and the lens to a preset value; Adjust the second distance between the lens and the imaging device so that the image of the aperture meets the target sharpness, and take the position of the imaging device corresponding to the image of the aperture meeting the target sharpness as the flat-top position of the flat-top laser.

[0006] In conjunction with the first aspect, in one feasible implementation, adjusting the second distance between the lens and the imaging device includes: After adjusting the first distance between the aperture of the aperture and the lens to a preset value, while keeping the position of the lens unchanged, the distance between the imaging device and the lens is adjusted to the second distance.

[0007] In conjunction with the first aspect, in one feasible implementation, the imaging device is specifically a template to be laser-drilled; Enabling the aperture of the aperture to form an image on the imaging device specifically includes: The flat-top laser is passed sequentially through the aperture of the aperture and the lens to drill a hole in the template. The shape of the drilled hole corresponds to the shape of the aperture image formed by the aperture.

[0008] In conjunction with the first aspect, in one feasible implementation, the aperture of the aperture is of a regular shape.

[0009] In conjunction with the first aspect, in one feasible implementation, the regular shape includes a square or a circle.

[0010] In conjunction with the first aspect, in one feasible implementation, adjusting the second distance between the imaging device and the lens includes: The reference value for the second spacing is determined based on the first spacing; A spacing range containing the reference value is set, and the template gradually increases or decreases the second spacing with the lens in the spacing range by a preset step size, and laser drilling is performed after the template moves by one step size.

[0011] In conjunction with the first aspect, in one feasible implementation, determining the reference value of the second spacing based on the first spacing includes: The first distance is set as the object distance u, and the image distance v is determined using the imaging formula 1 / f = 1 / u + 1 / v. The determined image distance v is used as the reference value of the second distance, where f is the focal length of the lens.

[0012] In conjunction with the first aspect, in one feasible implementation, making the imaging of the aperture conform to the target sharpness includes: The dimensions of the drilled hole shape after each step of laser drilling are measured on the template; The scale reference value d is calculated according to the formula D / d=u / v, where D is the scale of the aperture. The scale of the drill hole shape after each step of the template is moved is determined, and the error between the scale reference value d and the scale is determined. The image at the position of the template with the smallest error meets the target sharpness.

[0013] In conjunction with the first aspect, in one feasible implementation, measuring the scale of the drilled hole shape after each step of laser drilling on the template includes: The dimensions of the drill hole shape were measured using a microscope after each step of the template was moved.

[0014] Secondly, this application provides a flat-top laser position determination system, comprising: a laser generating device, an aperture, a lens, and an imaging device; the laser generating device is used to generate a flat-top laser. The laser generating device is used to allow the generated flat-top laser to pass sequentially through the aperture of the aperture and the lens, and to make the aperture of the aperture image on the imaging device. The aperture is used to adjust the first distance between the aperture aperture of the aperture and the lens to a preset value; The imaging device is used to adjust the second distance between itself and the lens so that the image of the aperture meets the target sharpness, and the position of the imaging device corresponding to the image of the aperture meeting the target sharpness is taken as the flat-top position of the flat-top laser.

[0015] In conjunction with the second aspect, in one feasible implementation, the aperture of the aperture is of a regular shape; the lens is a convex lens; and the imaging device is specifically a template to be laser-drilled.

[0016] The method and system for determining the flat-top position of a flat-top laser provided in this application first adjusts the basic optical path so that the flat-top laser generated by the laser generating device passes sequentially through the aperture of the aperture and the lens, so that the aperture of the aperture is imaged on the imaging device. Then, the first distance between the aperture and the lens is adjusted to a preset value, and then the second distance between the imaging device and the lens is adjusted so that the image of the aperture meets the target sharpness. At this time, the position of the imaging device corresponding to the image of the aperture meeting the target sharpness is the flat-top position of the flat-top laser. The adjustment steps of this application are simple and easy, and the flat-top position of the flat-top laser can be found quickly, thus improving the efficiency of debugging before laser operation. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a flat-top laser position determination system provided in an embodiment of this application; Figure 2This is a flowchart illustrating a method for determining the flat-top position of a flat-top laser provided in an embodiment of this application; Figures 3a to 3i This is a schematic diagram of the imaging device in the embodiments of this application. Detailed Implementation

[0019] To better understand the technical solution of the present invention, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0020] It should be understood that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0021] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0022] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0023] It should be understood that although the terms first, second, third, etc., may be used to describe terminals in the embodiments of the present invention, these terminals should not be limited to these terms. These terms are only used to distinguish terminals from each other. For example, without departing from the scope of the embodiments of the present invention, a first terminal may also be referred to as a second terminal, and similarly, a second terminal may also be referred to as a first terminal.

[0024] Depending on the context, the word "if" as used here can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."

[0025] As mentioned in the background section, existing technologies exist that convert laser light from a laser into a flat-top laser through a specific optical path. However, the laser light generated by the laser attenuates rapidly and has a short propagation distance after passing through the specific optical path. A unique flat-top position exists along its propagation path, defined as the cross-section where the laser energy distribution is most uniform. In existing technologies, the location of this flat-top position is typically determined first, and then used for laser drilling. However, the inventors have found that determining the flat-top position in existing technologies is cumbersome and inefficient. To solve the aforementioned technical problems, the inventive concept of this application was developed, which will be specifically described through the following embodiments.

[0026] See Figure 1 In one embodiment of this application, a flat-top laser flat-top position determination system is provided.

[0027] The flat-top laser flat-top position determination system in this application embodiment can quickly determine the flat-top position of the flat-top laser, improving the debugging efficiency before laser processing operations.

[0028] In this embodiment of the application, the flat-top laser flat-top position determination system includes: a laser generating device 101, an aperture 102, a lens 103, and an imaging device 104. The laser generating device 101 is used to generate a flat-top laser.

[0029] Specifically, the laser generating device 101 may include a laser that generates Gaussian laser and the necessary optical path to convert the Gaussian laser into a flat-top laser, so that the laser generating device 101 outputs a flat-top laser that can be transmitted over a certain distance.

[0030] The laser generating device 101 is used to make the generated flat-top laser pass through the aperture of the aperture 102 and the lens 103 in sequence, and to make the aperture of the aperture 102 image on the imaging device 104.

[0031] In one embodiment of this application, the aperture 102 has a regular aperture that allows a flat-top laser to pass through, so that the aperture can ultimately be imaged on the imaging device 104.

[0032] The aperture 102 can be adjusted to adjust the first distance between the aperture of the aperture 102 and the lens 103 to a preset value.

[0033] The position of the imaging device 104 can also be adjusted to adjust the second distance between it and the lens 103 so that the imaging of the aperture meets the target sharpness. At this time, the position of the imaging device is the flat top position of the flat top laser.

[0034] The energy distribution at the flat top of a flat-top laser is the most uniform, so the image at the corresponding position should be the clearest. In one embodiment, the clarity can be judged by how close the shape of the image is to the actual shape of the aperture. When the shape of the image is closest to the shape of the aperture, the image is also the clearest.

[0035] The flat-top laser flat-top position determination system provided in the above-described embodiments of this application first adjusts the basic optical path so that the flat-top laser generated by the laser generating device passes through the aperture of the aperture and the lens in sequence, so that the aperture of the aperture is imaged on the imaging device. Then, the first distance between the aperture and the lens is adjusted to a preset value, and then the second distance between the imaging device and the lens is adjusted so that the image of the aperture meets the target clarity. At this time, the position of the imaging device is the flat-top position of the flat-top laser. The adjustment steps of this application are simple and easy, and the flat-top position of the flat-top laser can be found quickly, which improves the efficiency of debugging before laser operation.

[0036] See Figure 2 One embodiment of this application provides a method for determining the flat-top position of a flat-top laser, which can be applied to... Figure 1 The system in the embodiment.

[0037] The method for determining the flat-top position using a laser in this application includes: S11, the flat-top laser generated by the laser generating device passes sequentially through the aperture of the aperture and the lens, and the aperture of the aperture is imaged on the imaging device; S12, adjust the first distance between the aperture of the aperture and the lens to a preset value; S13, adjust the second distance between the lens and the imaging device so that the imaging of the aperture meets the target sharpness, and take the position of the imaging device corresponding to the image of the aperture meeting the target sharpness as the flat-top position of the flat-top laser.

[0038] The method for determining the flat-top position of a flat-top laser provided in the above-described embodiments of this application first adjusts the basic optical path so that the flat-top laser generated by the laser generating device passes sequentially through the aperture of the aperture and the lens, so that the aperture of the aperture is imaged on the imaging device. Then, the first distance between the aperture and the lens is adjusted to a preset value, and then the second distance between the imaging device and the lens is adjusted so that the image of the aperture meets the target clarity. At this time, the position of the imaging device is the flat-top position of the flat-top laser. The adjustment steps of this application are simple and easy, and the flat-top position of the flat-top laser can be found quickly, which improves the efficiency of debugging before laser operation.

[0039] The following describes the process and advantages of the flat-top laser flat-top position determination method in a more detailed embodiment of this application.

[0040] S11, the flat-top laser generated by the laser generating device passes sequentially through the aperture of the aperture and the lens, and the aperture of the aperture is imaged on the imaging device; Specifically, this step is a process of adjusting the basic optical path, such as aligning the flat-top laser output from the laser generating device with the aperture, lens, and imaging device in a straight line, and ensuring that the center of the flat-top laser is coaxial with the optical center of the aperture and lens.

[0041] In one embodiment of this application, the aperture of the aperture is of a regular shape, such as a square or a circle. Therefore, the sharpness of the image can be determined by comparing the shape of the image with the actual shape of the aperture.

[0042] In the embodiments of this application, the lens may be a convex lens, thereby enabling the aperture to form a real image on the imaging device.

[0043] The imaging device can be a template to be laser-drilled. In this case, the flat-top laser passes through the aperture of the aperture and the lens in sequence to drill a hole in the template. It is easy to understand that the shape of the actual drilled hole corresponds to the shape of the image formed by the aperture of the aperture.

[0044] S12, adjust the first distance between the aperture of the aperture and the lens to a preset value.

[0045] Specifically, in the embodiments of this application, during the process of determining the flat top position, the first distance between the aperture and the lens is kept at a fixed value, which can be a preset value.

[0046] In this embodiment of the application, the preset value is 8.4m as an example.

[0047] S13, adjust the second distance between the lens and the imaging device so that the imaging of the aperture meets the target sharpness, and take the position of the imaging device corresponding to the image of the aperture meeting the target sharpness as the flat-top position of the flat-top laser.

[0048] In this embodiment, after adjusting the first distance between the aperture of the aperture and the lens to a preset value, the position of the lens is kept unchanged, and the distance between the imaging device and the lens is adjusted to a second distance.

[0049] Specifically, in this step, the position of the imaging device (template) can be adjusted multiple times, and the flat-top laser can be used to drill holes at each position. The clarity of the image can be judged by acquiring the shape data of the drill holes.

[0050] Before adjusting the second spacing, a reference value for the second spacing can be determined based on the first spacing. For example, the first spacing can be set as the object distance u, and the image distance v can be determined using the imaging formula 1 / f=1 / u+1 / v. The determined image distance v can be used as the reference value for the second spacing, where f is the focal length of the lens.

[0051] In a specific example, the first spacing u = 8.4m and the focal length of the lens f = 150mm, so the image distance v can be calculated to be 152.73mm. At this time, the reference value of the second spacing is also 152.73mm.

[0052] In this embodiment of the application, a spacing range including the reference value is further set, so that the template gradually increases or decreases the second spacing with the lens in the spacing range by a preset step size, and laser drilling is performed after the template moves by one step size.

[0053] In a specific example, the reference value is 152.73mm. The spacing range can be set from 152.43mm to 153.13mm, centered at 152.73mm, with a step size of 0.1mm. The initial position of the template can be set at 152.43mm. The template can move K times according to the step size. After each movement, laser drilling is performed, where K = 0, 1…8. The drilled hole shapes after each movement are as follows… Figures 3a to 3i The meaning is as shown.

[0054] In this embodiment of the application, the dimensions of the drilled hole shape after each step of the template is moved are measured using a high-magnification (e.g., 1000x) microscope.

[0055] exist Figures 3a to 3i In the example, the aperture is a square, and the aperture size is 2mm. 2mm.

[0056] The shape of the laser-drilled holes varies depending on the location of the template; for example, in... Figure 3a In the process, the shape of the borehole deviated somewhat from a square, with a specific dimension of 42.9 μm. 49.1µm. Similarly, the borehole shapes in the other attached figures can be obtained by microscopic measurement, which will not be elaborated here.

[0057] In this embodiment, the scale reference value d can be calculated according to the formula D / d=u / v, where D is the scale of the aperture. In the example of this application, when D is 2mm, the scale reference value d can be calculated to be 36.36um.

[0058] Furthermore, the scale of the drill hole shape after each step of the template is moved is determined, and the error between the drill hole shape and the scale reference value d is calculated. The image at the location of the template with the smallest error meets the target sharpness.

[0059] In a specific example, when the calculated scale reference value d is 36.36 μm, since the actual imaging may deviate from a square to some extent, the distance between the line segments of two mutually perpendicular edges can be measured during measurement, and the average value can be used as the scale of the borehole shape. For example, for... Figure 3a For example, the scale is (42.9 + 49.1) / 2 μm = 46 μm. Figure 3b For example, the scale is 46.9 μm, and so on, thus obtaining the scale of each actual borehole. Furthermore, it is easy to calculate. Figure 3e The borehole shape is 36.3 μm. 37.1 μm, used as a scale close to the scale reference value, Figure 3e The image is the clearest. Figure 3e The corresponding position of the template is the flat top position of the flat top laser.

[0060] In the embodiments of this application, since actual drilling involves measuring the distance between two vertical directions, the clarity of the image can be determined by calculating the variance or standard deviation of the two vertical distances and the scale reference value d. The smaller the variance or standard deviation, the clearer the image. The detailed calculation process will not be described here.

[0061] In the embodiments of this application, the shape of the aperture can also be circular. It is easy to understand that the closer the image is to a circle, the clearer it will be. When the actual image (or drilling) deviates from the circle, it is also necessary to measure two mutually perpendicular distances in order to obtain scale data. Of course, for a circle, data in more directions can also be measured, and the average of multiple measured data can be used as the scale of the drilling.

[0062] The flat-top laser flat-top position determination method provided in the above embodiments can quickly determine the position of the flat-top position. After determining the position of the flat-top position, laser drilling can be further performed on the PCB board material, and the drilling effect can be improved.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for determining the flat-top position using a laser, characterized in that, The method is applied to a flat-top laser position determination system, which includes a laser generating device, an aperture, a lens, and an imaging device. The laser generating device generates a flat-top laser, and the imaging device serves as a template. The method includes: The flat-top laser generated by the laser generating device is sequentially passed through the aperture of the aperture and the lens, and the aperture of the aperture is imaged on the imaging device; wherein, the imaged image of the aperture of the aperture is imaged on the imaging device specifically includes: the flat-top laser is sequentially passed through the aperture of the aperture and the lens, and a hole is drilled in the template, the shape of the drilled hole corresponding to the shape of the image formed by the aperture of the aperture; Adjust the first distance between the aperture of the aperture and the lens to a preset value; Adjust the second distance between the lens and the imaging device so that the image of the aperture meets the target sharpness, and take the position of the imaging device corresponding to the image of the aperture meeting the target sharpness as the flat-top position of the flat-top laser. The step of ensuring that the image of the aperture matches the target sharpness includes: The scale of the drill hole shape after each step of the template is moved is measured, and the scale of the drill hole shape is the average of the line segment distances between two mutually perpendicular edges of the actual image. The scale reference value d is calculated according to the formula D / d=u / v, where D is the scale of the aperture, u is the first spacing, and v is the reference value of the second spacing corresponding to each step the template moves. Determine the error between the scale of the borehole shape and the scale reference value d, wherein the image at the location of the template with the smallest error meets the target sharpness.

2. The method according to claim 1, characterized in that, Adjusting the second distance between the lens and the imaging device includes: After adjusting the first distance between the aperture of the aperture and the lens to a preset value, while keeping the position of the lens unchanged, the distance between the imaging device and the lens is adjusted to the second distance.

3. The method according to claim 1, characterized in that, Adjusting the second distance between the lens and the imaging device includes: The reference value for the second spacing is determined based on the first spacing; A spacing range containing the reference value is set, and the template gradually increases or decreases the second spacing with the lens in the spacing range by a preset step size, and laser drilling is performed after the template moves by one step size.

4. The method according to claim 3, characterized in that, The step of determining the reference value of the second spacing based on the first spacing includes: The first distance is set as the object distance u, and the image distance v is determined using the imaging formula 1 / f = 1 / u + 1 / v. The determined image distance v is used as the reference value of the second distance, where f is the focal length of the lens.

5. The method according to claim 1, characterized in that, The measurement of the drill hole shape of the template after each step of laser drilling includes: The dimensions of the drill hole shape were measured using a microscope after each step of the template was moved.

6. The method according to any one of claims 1-5, characterized in that, The aperture of the aperture is of a regular shape, including a square or a circle.

7. A flat-top laser positioning system, characterized in that, Includes: a laser generating device, an aperture, a lens, and an imaging device; the laser generating device is used to generate a flat-top laser, and the imaging device is a template; The laser generating device is used to allow the generated flat-top laser to pass sequentially through the aperture of the aperture and the lens, and to make the aperture of the aperture image on the imaging device. The aperture is used to adjust the first distance between the aperture aperture of the aperture and the lens to a preset value; The imaging device is used to adjust the second distance between itself and the lens so that the image of the aperture meets the target sharpness, and the position of the imaging device corresponding to the image of the aperture meeting the target sharpness is taken as the flat-top position of the flat-top laser.

8. The system according to claim 7, characterized in that, The aperture of the aperture is of a regular shape; the lens is a convex lens.

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