Laser etching machine

Abstract

The technical scheme of the utility model discloses a laser engraving machine. The laser engraving machine comprises a plurality of laser light sources and a focusing lens, the number of the reflecting pieces is the same as that of the laser light sources, and the reflecting pieces are arranged in laser paths of the multiple laser light sources in a one-to-one correspondence mode; the reflecting piece is used for changing the propagation direction of the laser, so that the reflected laser is emitted into the focusing lens in the same direction; the focusing lens is used for converging the laser reflected by the reflecting piece to form a light spot; an imaging lens; and the imaging lens is used for imaging the light spots to a carving surface. According to the laser engraving machine, laser of the multiple laser light sources is combined in a wedge light combination mode, the utilization rate of the lens is improved, more laser light sources can be arranged in the direction with the small laser light expansion amount, and the energy density of light spots and the power of the laser engraving machine are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of laser engraving machines, in particular to a laser engraving machine. Background Art

[0002] A laser engraving machine is a device that uses laser to engrave on the surface of an object or inside a transparent object. For different objects and processing scenarios, corresponding laser light sources are required.

[0003] In high-precision machining, the shape of the laser spot and the power of the laser engraving machine affect machining accuracy, machining efficiency, and material surface roughness. How to improve the output power of the laser engraving machine is an unresolved issue. Utility Model Content

[0004] The main purpose of the utility model is to provide a laser engraving machine, aiming to improve the power of the laser engraving machine.

[0005] In order to achieve the above-mentioned purpose, the present invention provides a laser engraving machine, which comprises:

[0006] Multiple laser light sources and focusing lenses;

[0007] The same number of reflectors as the number of laser light sources is provided in a one-to-one correspondence in the laser paths of the plurality of laser light sources; the reflectors are used to change the propagation direction of the laser light so that the reflected laser light enters the focusing lens in the same direction;

[0008] The focusing lens is used to converge the laser light reflected by the reflector to form a light spot;

[0009] Imaging lens; the imaging lens is used to image the light spot onto the engraving surface.

[0010] Optionally, the laser light source includes: a semiconductor laser diode; the semiconductor laser diode is used to emit laser.

[0011] Optionally, the reflective element is a reflector, and the reflector has an optical coating.

[0012] Optionally, the number of laser light sources in the direction of the laser slow axis is a first number, and the number of laser light sources in the direction of the laser fast axis is a second number; the first number is greater than the second number.

[0013] Optionally, the light spot is in a square shape.

[0014] Optionally, the focusing lens converges the lasers reflected by the multiple reflectors onto the optical axis and makes the spot size smaller than a preset value.

[0015] Optionally, the focusing lens is a biconical lens.

[0016] Optionally, the focusing lens and the imaging lens are arranged in parallel; the optical axis of the focusing lens coincides with the optical axis of the imaging lens.

[0017] The technical solution of the present utility model discloses a laser engraving machine, which includes: multiple laser light sources and focusing lenses; a number of reflectors equal to the number of laser light sources, wherein the reflectors are arranged in a one-to-one correspondence in the laser paths of the multiple laser light sources; the reflectors are used to change the propagation direction of the laser light so that the reflected laser light enters the focusing lens in the same direction; the focusing lens is used to converge the laser light reflected by the reflectors to form a light spot; and an imaging lens; the imaging lens is used to image the light spot onto the engraving surface. The utility model combines the laser light of multiple laser light sources by using a wedge-shaped light combining method, thereby improving the utilization rate of the lens, and being able to arrange more laser light sources in the direction with small laser light emission, thereby increasing the energy density of the light spot and the power of the laser engraving machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0019] Figure 1 This is a schematic diagram of the laser in the direction of the laser slow axis of an embodiment of the laser engraving machine of the present utility model;

[0020] Figure 2 This is a schematic diagram of the laser in the fast axis direction of an embodiment of the laser engraving machine of the present utility model;

[0021] Figure 3 This is a laser imaging spot diagram of an embodiment of the laser engraving machine of the present utility model;

[0022] Figure 4 This is a schematic diagram of the optical path of an embodiment of the laser engraving machine of the present invention.

[0023] Description of Figure Numbers:

[0024]

[0025] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0028] In this utility model, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. For those skilled in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0029] In addition, in this utility model, the descriptions of "first" and "second" are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features specified as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this utility model.

[0030] This proposal proposes a laser engraving machine for laser engraving on or within objects. During the engraving process, laser power and laser spot shape directly influence the engraving effect. The laser's etendue affects the spot shape and laser focus energy density. A greater etendue results in greater laser divergence and lower spot energy density. Furthermore, spot shape significantly impacts the engraving effect. Specifically, a circular or nearly circular spot shape produces smoother straight lines. A long, rectangular or elliptical spot may result in uneven edges when engraving straight lines. An irregularly shaped spot may result in areas of excessive depth or shallowness when engraving curved lines, affecting the curve's aesthetics and precision. For complex patterns, varying spot shapes can produce different effects. For example, a long, rectangular spot can quickly engrave a large background, while a circular spot can highlight key areas of a pattern. However, choosing the wrong spot shape can make complex patterns appear chaotic.

[0031] It is easy to see that the shape of the laser spot is affected by the etendue of the laser light source 1 in the fast axis and slow axis directions. In addition, since the etendue of the laser light source 1 in the two directions is different, and the lenses in the laser engraving machine are mostly circular lenses, the different etendues in the two directions will lead to different lens utilization rates in the two directions. Figures 1 to 3 As shown, Figure 1 is a schematic diagram of the laser in the direction of the laser slow axis, Figure 2 is a schematic diagram of the laser in the direction of the laser fast axis, Figure 3 This is a diagram of the laser imaging spot. The light source divergence angle in the fast axis direction is greater than that in the slow axis direction. To improve lens utilization and spot energy, this solution combines the beams of multiple laser sources 1 using a wedge-shaped beam combining method. Adjusting the number of laser sources 1 positioned in the slow axis direction improves lens utilization in that direction, thereby changing the spot shape of the combined laser and increasing the energy density of the spot and the power of the laser engraving machine.

[0032] Reference Figure 4 The present invention provides a laser engraving machine, which includes:

[0033] Multiple laser light sources 1 and focusing lenses 3;

[0034] The same number of reflectors 2 as the number of laser light sources 1 are provided in a one-to-one correspondence in the laser paths of the plurality of laser light sources 1; the reflectors 2 are used to change the propagation direction of the laser light so that the reflected laser light enters the focusing lens 3 in the same direction;

[0035] The focusing lens 3 is used to converge the laser light reflected by the reflector 2 to form a light spot;

[0036] Imaging lens 4; the imaging lens 4 is used to image the light spot onto the engraving surface.

[0037] It should be noted that the laser light source 1 is used to generate laser light. The laser light source 1 can be a gas laser, such as a carbon dioxide laser and a helium-neon laser; a solid-state laser, such as a ruby ​​laser and a neodymium-doped yttrium aluminum garnet laser; a semiconductor laser, such as a laser diode; or a fiber laser. In particular, the laser light source 1 comprises a semiconductor laser diode, which emits laser light. Furthermore, in this embodiment, the laser light emitted by multiple laser light sources 1 is combined after passing through the reflector 2; the multiple laser light sources 1 emit laser light of the same wavelength.

[0038] There are multiple reflectors 2. Specifically, the number of reflectors 2 matches the number of laser light sources 1. There is one reflector 2 in the laser path of each laser light source 1. That is, the reflectors 2 are arranged one-to-one in the laser paths of the multiple laser light sources 1 to change the laser paths. It should be noted that the solution proposed in the present invention has the same number of reflectors 2 as the laser light sources 1. Compared to the solution in which the laser light is directly incident on the focusing lens 3, the solution proposed in the present invention uses the same number of reflectors 2 as the laser light sources 1 to change the propagation direction of the laser light reflected by each corresponding laser light source 1. It is easy to understand that if there is laser light directly incident on the focusing lens 3, the laser light source 1 emitting the laser light needs to have an appropriate axial position and angular relationship with the focusing lens 3. In addition, since there is laser light directly incident on the focusing lens 3 in space, the reflectors 2 cannot be located in the laser path of the laser light. This will limit the spatial distribution of the reflectors 2, reduce the number of reflectors 2, and thus reduce the number of laser light sources 1 that can reflect the laser light to the focusing lens 3. In addition, this solution uses reflectors 2 that are arranged one-to-one in the laser paths of multiple laser light sources 1. By changing the spatial position of the reflectors 2, the incident and / or emission directions of the lasers can be adjusted, thereby allowing the position of the laser light sources 1 and the focusing lens 3 to change. This provides a method for quickly restoring the normal operation of the laser engraving machine when the position of the laser light source 1 or the focusing lens 3 changes. When the position of the laser light source 1 or the focusing lens 3 changes, only the position of the reflector 2 needs to be changed.

[0039] Reference Figures 1 to 3, due to the different divergence angles of the light source in the fast and slow axis directions of the laser, the utilization rate of the lens for a single light source in the two directions is different. The laser beam divergence angle in the slow axis direction is larger, and the spot size is larger, which means that there is more space in the slow axis direction to accommodate the beams of multiple laser light sources 1 for superposition. When multiple laser light sources 1 are combined in the slow axis direction, the space can be used more effectively, and the energy of different light sources can be concentrated, thereby increasing the power intensity after combining. The beam divergence angle in the fast axis direction is smaller, and the spot size is smaller. Increasing the number of laser light sources 1 in this direction will face spatial limitations, making it difficult to achieve effective superposition of multiple light beams. Moreover, the beam quality in the fast axis direction is higher, and increasing the number of light sources may introduce more optical errors and interference, which in turn affects the beam quality and power intensity after combining. Reference Figure 4 In this solution, lasers emitted by multiple laser light sources 1 are reflected, and the reflected lasers are incident on focusing lens 3 in the same direction. When all the beams are combined into a single beam, it can be seen that the beam quality along the fast axis remains unchanged, while the multiple beams along the slow axis are closely arranged, increasing the optical parameter product along the slow axis. Therefore, when performing spatial beam combining, the dark area between the light spots is minimized, thereby improving the laser output power and laser brightness.

[0040] The reflected laser light is output to the focusing lens 3. Since the laser light source 1 outputs lasers of the same wavelength, multiple laser beams are combined and output to the focusing lens 3. The focusing lens 3 focuses the combined laser beams to form a light spot. The imaging lens 4 images the light spot onto the engraving surface of the engraving material. The imaging lens 4 can correct and optimize the projected image, improving the image clarity and resolution, reducing image distortion and blur, and achieving a more perfect engraving effect.

[0041] It should be noted that the number of lasers on the laser fast and slow axes is determined by the R&D personnel, and the spatial position relationship between the laser light source 1, the reflector 2 and the focusing lens 3 can be changed accordingly.

[0042] Reference Figure 4Laser light emitted from the reflector 2 enters the focusing lens 3. Laser light reflected by multiple reflectors 2 enters different areas of the focusing lens 3, utilizing areas that would not be available if a single light source were input. This improves lens utilization. Furthermore, it is readily apparent that the laser fast and slow axes are perpendicular to each other. Reflection by the reflector 2 does not alter the perpendicular relationship between the fast and slow axes. Changing the number of laser light sources 1 in the fast and slow axis directions changes the lens utilization of the focusing lens 3 in a pair of perpendicular directions, thereby altering the shape of the combined laser beam after convergence through the focusing lens 3. Adding a light source in the slow axis direction increases the lens utilization in the direction corresponding to the slow axis of the focusing lens 3. It is readily understood that light from the additional light source in the slow axis direction, after reflection from the reflector 2, generally enters a mirrored position near the edge of the focusing lens 3. After convergence through the focusing lens 3, this light will expand in the direction corresponding to the slow axis of the original spot. For example, if the spot shape originally formed by the laser light source 1 is elliptical, adding a laser light source 1 in the slow axis direction may change it to a circular shape.

[0043] In addition, it should be noted that the multiple beams of laser light emitted from the reflector 2 are incident in parallel on the focusing lens 3, that is, the light rays in the fast axis direction of the combined laser beam are parallel to each other, and the light rays in the slow axis direction are parallel to each other; after being focused by the focusing lens 3, the combined laser beam can form a rectangular spot shape. If the light emission in the fast axis and the slow axis are equal, a square spot shape can be formed. Since the light emission in the fast axis direction of the laser is greater than the light emission in the slow axis direction, if a square spot needs to be formed in the end, the number of laser light sources 1 in the slow axis direction of the laser is greater than the laser light source 1 in the fast axis direction. In particular, the laser light source 1 includes: a semiconductor laser diode; the semiconductor laser diode is used to emit laser light. Increasing the number of light sources in the slow axis direction of the laser diode can change the spot shape. When the number of laser light sources 1 in the slow axis direction of the laser is greater than the number of laser light sources 1 in the fast axis direction by a certain amount, the spot shape can be square.

[0044] It is easy to see that by changing the number of laser light sources 1 in the fast and slow axis directions, the shape of the light spot formed by the combined laser beam through the focusing lens 3 can be changed to meet the laser spot requirements of different materials to be engraved. In addition, because the laser light from multiple laser light sources 1 is combined by the wedge-shaped light combining method, the lens utilization rate is improved, and more laser light sources 1 can be arranged in the direction of small laser light emission, which increases the energy density of the light spot and the power of the laser engraving machine.

[0045] Specifically, due to the larger beam divergence angle and larger spot size along the slow axis of the laser, there is more space along the slow axis to accommodate the superposition of beams from multiple laser light sources 1. When multiple laser light sources 1 are combined along the slow axis, space can be more efficiently utilized, concentrating the energy from the different light sources and increasing the combined power intensity. The number of laser light sources 1 along the slow axis is a first number, and the number of laser light sources 1 along the fast axis is a second number; the first number is greater than the second number.

[0046] The reflector 2 can be a reflector, a reflective prism, or a metal film reflector. In one example, the reflector 2 is a reflector having an optical coating. The optical coating can increase the reflectivity of the laser and reduce scattering and absorption. Furthermore, the coating can also protect the surface of the reflector.

[0047] In one specific embodiment, the focusing lens 3 converges the laser light reflected from the multiple reflectors 2 onto the optical axis, reducing the spot size to a predetermined value. It should be noted that when laser light is not focused, its energy is relatively dispersed. The focusing lens 3 converges the laser beam to a very small point, significantly increasing the energy density at that point. This is crucial for the laser engraving process, as only sufficiently high energy can cause the material surface to melt, vaporize, or chemically react, thereby achieving the engraving effect. For example, when engraving hard metal materials, a high-energy-density laser beam is required to create clear patterns and text on the surface.

[0048] Furthermore, the focused laser beam has a very small diameter, enabling high-precision engraving. By adjusting the parameters of focusing lens 3, the position and size of the laser beam's focal point can be precisely controlled to meet varying engraving precision requirements. For applications requiring fine engraving, such as marking electronic components and engraving jewelry, focusing lens 3 ensures clear, accurate engraving details.

[0049] Therefore, the size of the laser spot directly determines the engraving effect of the laser engraving machine; the spatial position relationship between the focusing lens 3 and the reflector needs to be adjusted to make the laser spot size smaller than the preset value so that the laser engraving machine can achieve the required engraving requirements. The preset value is determined by the R&D personnel.

[0050] The focusing lens 3 is a biconical lens, and the focusing lens 3 has different curvatures in the fast and slow axes of the incident laser.

[0051] It is easy to understand that the double-cone design can more accurately focus the laser beam onto a very small point when passing through the focusing lens 3. Compared with traditional single-curved lenses, the double-cone surface can better control the propagation path of the laser, reduce the scattering and aberration of the light beam, and thus improve the focusing accuracy. The double-cone surface of the focusing lens 3 can increase the depth of focus to a certain extent. Traditional single-curved lenses usually have a shallow depth of focus. When the material surface is uneven or thicker materials need to be processed, inaccurate focusing or poor processing results may occur.

[0052] The biconical lens can optimize the focusing characteristics of the light beam, so that the laser can maintain a high energy density within a larger depth range, thereby improving the adaptability to materials of different thicknesses. The biconical focusing lens 3 can adjust the shape of the laser beam so that it forms a more regular light spot after focusing. For example, for some processing tasks with special shape requirements, such as circular, square or elliptical light spots, the biconical lens can achieve the required light spot shape through precise design. This is beneficial to the control of the shape of the light spot in this solution. In addition, the laser beam will gradually diverge during the propagation process, which will affect the focusing effect and processing accuracy. The biconical focusing lens 3 can control the divergence angle of the laser beam by adjusting the angle and curvature of the cone surface, so that it maintains a smaller degree of divergence after focusing. This is beneficial to improving the energy density of the light spot.

[0053] In order to reduce energy loss of the laser during propagation, the focusing lens 3 and the imaging lens 4 are arranged in parallel; the optical axis of the focusing lens 3 and the optical axis of the imaging lens 4 coincide with each other.

[0054] The above description is merely an optional embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made by utilizing the contents of the present invention specification and drawings under the inventive concept of the present invention, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A laser engraving machine, characterized in that: The laser engraving machine includes: Multiple laser light sources and focusing lenses; The same number of reflectors as the number of laser light sources is provided in a one-to-one correspondence in the laser paths of the plurality of laser light sources; the reflectors are used to change the propagation direction of the laser light so that the reflected laser light enters the focusing lens in the same direction; The focusing lens is used to converge the laser light reflected by the reflector to form a light spot; Imaging lens; the imaging lens is used to image the light spot onto the engraving surface.

2. The laser engraving machine according to claim 1, characterized in that: The laser light source includes: a semiconductor laser diode; the semiconductor laser diode is used for emitting laser light.

3. The laser engraving machine according to claim 2, characterized in that: The reflector is a reflector having an optical coating.

4. The laser engraving machine according to any one of claims 1 to 3, characterized in that: The number of laser light sources in the direction of the laser slow axis is a first number, and the number of laser light sources in the direction of the laser fast axis is a second number; the first number is greater than the second number.

5. The laser engraving machine according to claim 4, characterized in that: The light spot is in a square shape.

6. The laser engraving machine according to claim 4, characterized in that: The focusing lens converges the lasers reflected by the multiple reflectors onto the optical axis and makes the light spot size smaller than a preset value.

7. The laser engraving machine according to claim 6, characterized in that: The focusing lens is a biconical lens.

8. The laser engraving machine according to claim 4, characterized in that: The focusing lens and the imaging lens are arranged in parallel; the optical axis of the focusing lens coincides with the optical axis of the imaging lens.

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