Dimming system for light spot adjustment, and processing device

Abstract

A dimming system for light spot adjustment, and a processing device. The dimming system comprises: a light source module, which is used for emitting a light beam in a predetermined direction; an adjustment module, which is used for receiving the light beam and adjusting the light spot size of the light beam; and a beam compression module, which is arranged between the light source module and the adjustment module along the propagation direction of the light beam, and is used for compressing the size of the light beam before the light beam enters the adjustment module. While keeping specifications of an original optical system such as the maximum light spot size and uniformity unchanged, the system reduces, by means of a beam compression module, the size of a light beam entering an adjustment module, thereby expanding the range of light spot scaling, and ensuring that the structural layout of the original system remains unaffected.

Description

A dimming system and processing equipment for adjusting light spot size. Technical Field

[0001] This invention relates to the field of laser processing, and more particularly to a dimming system and processing equipment for adjusting laser spot size. Background Technology

[0002] Variable laser processing (VLS) is an advanced method for processing materials using laser technology. Unlike traditional laser processing methods, VLS is characterized by its ability to adjust laser parameters, such as power, wavelength, pulse width, and frequency, in real time according to different processing requirements and material properties. This flexibility makes it a promising candidate for applications in various fields.

[0003] In modern industry, variable laser processing is widely used in manufacturing and high-tech sectors. For example, in precision manufacturing, it enables high-precision cutting and drilling of various materials such as metals, ceramics, and plastics. In the automotive and aerospace industries, this technology is used to manufacture complex parts and structures, significantly improving production efficiency and product quality due to its high efficiency and accuracy. Furthermore, variable laser processing plays a crucial role in the production of electronic devices, medical instruments, and optical components, especially in scenarios requiring highly controlled processing conditions.

[0004] As the application of variable laser uniform rectangular spots in industrial processing continues to expand, the requirements for spot performance indicators are becoming increasingly stringent. These indicators include the spot variation rate, uniformity, and stability. The spot variation rate refers to the range and degree to which the laser spot can be adjusted during processing, and is usually a key factor determining processing efficiency and accuracy. Uniformity involves the distribution of light intensity within the spot, which directly affects the uniformity of material heating and processing quality.

[0005] However, existing variable spot size systems still face certain challenges in these aspects. Specifically, existing technologies often fail to fully meet the increasingly complex application requirements when adjusting the spot size scaling factor. The spot size scaling factor may be limited by the system design or technological level, resulting in the inability to achieve the ideal spot size range or adjustment accuracy in practical applications. In addition, the uniformity of the spot size also affects the processing quality to some extent, especially in high-precision or high-requirement processing tasks, where insufficient spot uniformity may lead to unstable processing results or defects. Summary of the Invention

[0006] To address the aforementioned technical problems, embodiments of the present invention aim to provide a dimming system and processing equipment for adjusting light spots, thereby improving the magnification of light spot variation while ensuring light spot quality.

[0007] The technical solution of this invention is implemented as follows:

[0008] In a first aspect, embodiments of the present invention provide a dimming system for adjusting light spot size, the dimming system comprising: a light source module for emitting a light beam in a predetermined direction; an adjustment module for receiving the light beam and adjusting the light spot size of the light beam; and a beam-shrinking module disposed between the light source module and the adjustment module according to the light beam propagation direction, the beam-shrinking module for compressing the light beam size before the light beam enters the adjustment module.

[0009] Preferably, the beam-shrinking module includes at least one array lens, and the adjustment module includes a first diffuser and a second diffuser. The surface of the first diffuser has a microstructure. The first diffuser receives the light beam before the second diffuser and compresses the size of the light beam in a single channel through the array lens, so that the size of the light beam entering each individual channel of the first diffuser becomes smaller.

[0010] Preferably, the array lens has the same pitch as the first diffuser. In this case, the channel of each array lens corresponds to each channel of the first diffuser, and the beam can be transmitted precisely in the corresponding two channels. This makes the beam size leaving the beam array lens smaller than the pitch of the first diffuser, thus avoiding defects such as cross-channeling and light leakage.

[0011] Preferably, the magnification of the array lens satisfies the following equation:

[0012] Where Y is the beam reduction ratio of the array lens, h is the pitch of the first diffuser, l is the optical path length of the array lens from the first diffuser, and θ is the divergence angle of the beam. By using the above calculation formula, the required target parameters are obtained based on the known parameters, thereby selecting a suitable device, thus expanding the adaptability of the dimming system and saving costs.

[0013] Preferably, both sides of the array lens are convex arrays.

[0014] Preferably, the two sides of the array lens are a convex array and a concave array, respectively, along the propagation direction of the light beam.

[0015] Secondly, embodiments of the present invention also provide a processing device that uses a variable laser for processing, and the processing device includes the dimming system described in any of the above claims.

[0016] The dimming system for beam adjustment disclosed in this embodiment of the invention can effectively reduce the size of the beam entering the adjustment module by setting a beam shrinking module before the adjustment module, thereby ensuring the beam quality when the adjustment module adjusts the beam at a large magnification, and thus increasing the beam adjustment magnification of the dimming system. Attached Figure Description

[0017] Figure 1 shows a prior art device for achieving light spot variation according to the present invention;

[0018] Figure 2 is another state diagram of the existing device used to realize the change of light spot in the prior art of the present invention;

[0019] Figure 3 is a schematic diagram of a dimming system according to an embodiment of the present invention;

[0020] Figure 4 is another schematic diagram of a dimming system according to an embodiment of the present invention;

[0021] Figure 5 is a schematic diagram of light leakage detected in the prior art of the present invention;

[0022] Figure 6 is a diagram showing the effect of monitoring diffraction side peaks in the prior art of the present invention;

[0023] Figure 7 is a schematic diagram of the light spot deformation detected in the prior art of the present invention. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0025] In variable spot systems, adjusting the spot size aims to alter the beam's resolution, accuracy, and energy density for specific applications. The spot size directly affects the beam's effective area and impact on the target object. Generally, a smaller spot size concentrates more energy into a smaller area, making it suitable for precision machining, microstructure fabrication, and high-resolution imaging. Existing technologies use optical lenses or lens systems to focus the collimated beam into a smaller spot size. Typically, the shorter the focal length of the lens, the smaller the focused spot.

[0026] A diffuser is an optical element or material used to distribute light emitted from a light source more evenly, reduce light spots and shadows, and can also be used to adjust the size of the light beam. Referring to Figure 1, which shows a prior art device 10 for achieving light spot variation, it includes a diffuser module formed by two diffusers arranged along the light propagation direction. A fixed diffuser 101, which receives the light beam, is fixed in its position and processes the beam. A movable diffuser 102 receives the beam shaped by the fixed diffuser 101 and moves between positions 1 and 2 in Figure 1 along the aforementioned propagation direction.

[0027] When the distance between the movable diffuser 102 and the fixed diffuser 101 is the focal length of the fixed diffuser 101, i.e., when the movable diffuser 102 is at position 1, the light beam passes sequentially through the fixed diffuser 101 and the movable diffuser 102 to achieve minimum magnification adjustment. In this state, the light beam can achieve minimum magnification scaling. Simultaneously, when the movable diffuser 102 moves along the light propagation direction, i.e., in the direction indicated by arrow x in Figure 1, the adjustment magnification can be further increased, meaning the light spot can be further reduced. Using the device shown in Figure 1, when the movable diffuser 102 moves from position 1 to position 2, the light spot magnification varies between 4 and 5 times.

[0028] Referring to Figure 2, as the distance between the fixed diffuser 101 and the movable diffuser 102 increases to its limit, exemplarily, when the movable diffuser 102 moves from position 1 to position 3 in Figure 2, referring to Figures 1 and 2, when the movable diffuser 102 is at positions 2 and 3 respectively, the light beam processed by the movable diffuser 102 exhibits normal and light leakage effects, respectively, as indicated by A and B in Figures 1 and 2. Here, the aforementioned limit refers to the point where, after the distance between the fixed diffuser 101 and the movable diffuser 102 exceeds this limit, the scaled light spot begins to exhibit light spot quality problems, such as light leakage, diffraction side peaks, and rectangular distortion. This is because when the light spot after passing through the fixed diffuser 101 has already been adjusted to a relatively wide range, the distance between the movable diffuser 102 and the fixed diffuser 101 is too large, making it impossible to effectively further homogenize the light beam, resulting in uneven intensity distribution at the center and edges of the light spot. Furthermore, the beam scatters at a large angle after passing through the fixed diffuser 101. This large adjustment angle causes the beam to experience more interference and overlap effects in the moving diffuser 102, leading to blurred edges or interference fringes on the beam spot, thus affecting the overall clarity and quality of the beam spot. Therefore, the maximum adjustment magnification of the beam spot is limited by the limits between the fixed diffuser 101 and the moving diffuser 102. Typically, the magnification of the beam spot in the devices shown in Figures 1 and 2 does not exceed 7 times. When the magnification exceeds 7 times, beam spot quality problems occur. For example, see Figures 5 to 7, which respectively illustrate schematic diagrams of beam spot quality problems occurring when the beam spot magnification is large. Figure 5 shows a schematic diagram of light leakage when the magnification of the existing device is too high. Figure 6 shows a schematic diagram of beam spot defects with diffraction side peaks when monitoring the existing device. In Figure 6, point C indicates the monitoring effect of the diffraction side peaks. Furthermore, Figure 7 shows a schematic diagram of rectangular deformation of the beam spot when monitoring the existing device.

[0029] Based on the above problems, embodiments of the present invention provide a dimming system for adjusting light spot size. While maintaining the maximum spot size, uniformity, and other indicators of the original optical system unchanged, the dimming system reduces the beam size of the beam entering the adjustment module in advance by setting a beam shrinking module between the light source and the adjustment module, ensuring that the original system structure layout is not affected, thereby increasing the beam size variation factor and ensuring the beam quality. It should be noted that here, the beam size refers to the spot size of the beam.

[0030] Referring to Figure 3, a dimming system 30 according to an embodiment of the present invention is shown. The dimming system 30 includes a light source module (not shown), an adjustment module 32, and a beam-shrinking module 33. Referring to Figure 3, the light source module emits a light beam in a predetermined direction, and the adjustment module 32 adjusts the spot size of the light beam. The light source module emits the light beam in the direction indicated by the X arrow. The beam-shrinking module 33 is disposed between the light source module and the adjustment module 32. The beam-shrinking module 33 receives the light beam emitted by the light source and compresses the light beam. The compressed light beam is received by the adjustment module 32 and thus adjusted. With this structure, the beam is compressed by the beam-shrinking module 33 before the adjustment module 32. Compared to a light beam directly emitted by the light source entering the adjustment module 32, the compressed beam achieves the technical effect of expanding the minimum spot size, without affecting the original structural layout of the light source and the adjustment module 32.

[0031] Preferably, the beam-shrinking module 33 includes at least one array lens 331, the surface of which includes a plurality of microlenses arranged side-by-side along a direction perpendicular to the light propagation direction. The array lens 331 is configured such that both sides are convex, or that it is convex and concave sequentially along the light propagation direction. These two surface configurations allow for adjustment of the beam size and reduction of the beam spot size. Preferably, the array lens 331 is configured with both sides being convex and concave. This configuration prevents the light beam from focusing inside the array lens 331 when passing through it, further preventing the focus inside the array lens from increasing the temperature of the optical components when the beam power is high.

[0032] Meanwhile, the adjustment module 32 includes a first diffuser 321 and a second diffuser 322. The first diffuser 321 is fixed in position, and the second diffuser 322 can be translated between position 1 and position 4 along the beam propagation direction. The second diffuser 322 is preferably a standard diffuser. Both the first diffuser 321 and the second diffuser 322 have microstructures on their surfaces. The specific microstructures are not limited, as long as they can achieve the effect of adjusting the magnification of the beam spot size. The adjustment module 32 adjusts the distance between the first diffuser 321 and the second diffuser 322 by moving the second diffuser 322, thereby achieving the effect of adjusting the beam. The first diffuser 321 is located between the second diffuser 322 and the array lens 331, and the first diffuser 321 receives the beam compressed by the array lens 331. With the arrangement of the array lenses described above, while the beam is compressed by the beam-shrinking module 33, the multiple array lenses can divide the beam into multiple sub-beams. The multiple sub-beams specifically enter the first diffuser 321. At the same time, the surface of the first diffuser 321 has microstructures. By dividing and processing the beam, the technical effect of beam shrinking and reducing the light spot is further enhanced.

[0033] Furthermore, the array lens 331 and the first diffuser 321 share the same pitch in their microstructure. In a microlens array, pitch refers to the distance between the center points of adjacent microlenses. This is an important geometric parameter used to describe the density and layout of the microlens array. Specifically, pitch is an indicator of the tightness of the arrangement of microlenses in a microlens array. It is typically measured in micrometers (μm) and represents the distance from the center of one microlens to the center of the next. The size of the pitch directly affects the optical performance of the array. For example, in imaging applications, pitch affects resolution; in illumination applications, pitch affects light uniformity. When transmitting a light beam, each sub-channel of the array lens 331 has a corresponding channel located on the first diffuser 321, and the light beam always propagates within the corresponding two channels. Simultaneously, after each sub-beam leaves the channel of the array lens 331, the beam size shrinks to a size smaller than the corresponding channel on the first diffuser 321, allowing the sub-beam to enter the corresponding channel on the first diffuser 321 more precisely.

[0034] When the array lens 331 and the first diffuser 321 have the same pitch, it can ensure that the compressed beam has high alignment when propagating between the beam-shrinking array lens and the first diffuser 321, thus ensuring high-efficiency optical performance. When the sub-beam enters from a sub-channel of the array lens 331 into a corresponding channel on the first diffuser 321, it avoids defects such as crosstalk between different beams in different channels.

[0035] Specifically, referring to Figure 4, when the array lens 331 has the same pitch as the microstructure of the first diffuser 321, the magnification Y of the array lens 331 satisfies the following relationship:

[0036] Where Y is the beam reduction magnification of the array lens 331, h is the pitch of the first diffuser 321, l is the optical path length of the array lens 331 from the first diffuser 321, and θ is the divergence angle of the beam incident on the array lens 331. Through the above structure and relationships, once a person skilled in the art knows one or more of these parameters, they can calculate other parameters and design the dimming system based on the above formula. For example, when the target magnification Y of the array lens is known, different h values ​​can be obtained using existing diffusers. Simultaneously, the divergence angle θ of the beam can be obtained based on collimation. Therefore, the distance between the array lens and the first diffuser can be calculated based on the above formula. Similarly, when the positions of the system components are limited, knowing the target beam reduction magnification of the array lens allows for the selection of a suitable diffuser to provide the optimal pitch value. Based on the pitch value calculated using the above formula, an existing diffuser can be selected, or a new diffuser can be redesigned, thereby controlling the cost of the entire dimming system. Based on the above formula and the target beam reduction magnification, adjusting the optical parameters of the beam-reducing lens array and the first diffuser can achieve designs that meet various optical requirements.

[0037] Based on the dimming system 30 disclosed in the above embodiments, this embodiment of the invention also discloses a processing device, which uses a variable laser for processing, and the variable laser is implemented by the dimming system 30 disclosed in any of the above embodiments of the invention.

[0038] It should be noted that the technical solutions described in the embodiments of the present invention can be combined arbitrarily without conflict.

[0039] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A dimming system for adjusting light spot size, characterized in that, The dimming system includes: A light source module, which is used to emit a light beam in a predetermined direction; An adjustment module is used to receive the light beam and adjust the spot size of the light beam; And a beam-shrinking module disposed between the light source module and the adjustment module according to the propagation direction of the light beam, the beam-shrinking module being used to compress the beam size of the light beam before the light beam enters the adjustment module.

2. The dimming system according to claim 1, characterized in that, The beam-shrinking module includes at least one array lens, and the adjustment module includes a first diffuser and a second diffuser. The surface of the first diffuser has a microstructure, and the first diffuser receives the beam before the second diffuser.

3. The dimming system according to claim 2, characterized in that, The array lens has the same pitch as the microstructure of the first diffuser.

4. The dimming system according to claim 3, characterized in that, The magnification of the array lens satisfies the following equation: Where Y is the beam reduction ratio of the array lens, h is the pitch of the first diffuser, l is the optical path length of the array lens from the first diffuser, and θ is the divergence angle of the beam.

5. The dimming system according to claim 2, characterized in that, Both sides of the array lens are convex arrays.

6. The dimming system according to claim 2, characterized in that, The two sides of the array lens are, in sequence, a convex array and a concave array along the propagation direction of the light beam.

7. A processing apparatus, wherein the processing apparatus uses a variable laser for processing, characterized in that, The processing equipment includes the dimming system according to any one of claims 1 to 4.

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