Optical lens and laser processing system

Abstract

The embodiment of the utility model provides an optical lens. The optical lens sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens in the laser incidence direction. The first lens is a biconvex lens; the second lens is a biconcave lens; the third lens is a meniscus lens, and the convex surface direction is consistent with the laser incident direction; the fourth lens is a meniscus lens, and the convex surface direction is consistent with the laser incident direction; the fifth lens is a meniscus lens, and the convex surface direction is consistent with the laser incident direction; the sixth lens is a biconvex lens; the seventh lens is a protection flat plate.

Description

Technical Field

[0001] This specification relates to the field of optics, and in particular to an optical lens and a laser processing system. Background Technology

[0002] Optical lenses play a crucial role in applications such as scanning marking and drilling. Ultraviolet (UV) optical lenses, due to their shorter wavelengths and higher energy, are particularly effective in applications like drilling and edge trimming.

[0003] When used in industrial applications, the 343nm wavelength presents challenges due to the inherent characteristics of the ultraviolet band. When large-angle incident light spots are compressed to the usable size, field curvature, distortion, and image telecentrism become difficult to control. For existing conventional F-theta lenses, because the laser at the center of the lens is focused perpendicularly onto the processing plane, while the laser at the edges is focused at an angle, the light spot at the center is circular while the light spot at the edges is elliptical. This results in inconsistencies between the center and edge effects during precision machining.

[0004] Therefore, there is a need to provide an optical lens that can meet the high precision requirements of laser processing. Utility Model Content

[0005] This specification provides one or more embodiments of an optical lens, which sequentially includes: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens along the laser incident direction; the first lens is a biconvex lens; the second lens is a biconcave lens; the third lens is a meniscus lens with its convex surface aligned with the laser incident direction; the fourth lens is a meniscus lens with its convex surface aligned with the laser incident direction; the fifth lens is a meniscus lens with its convex surface aligned with the laser incident direction; the sixth lens is a biconvex lens; and the seventh lens is a protective plate.

[0006] In some embodiments, the first radius of curvature of the first lens is in the range of 90-95 mm, the second radius of curvature of the first lens is in the range of (-355)-(-350) mm; the third radius of curvature of the second lens is in the range of (-108)-(-102) mm, the fourth radius of curvature of the second lens is in the range of 118-125 mm; the fifth radius of curvature of the third lens is in the range of (-143)-(-138) mm, and the sixth radius of curvature of the third lens is in the range of (-84)-(-79) mm; The seventh radius of curvature of the fourth lens is in the range of (-84) to (-79) mm, the eighth radius of curvature of the fourth lens is in the range of (-194) to (-189) mm; the ninth radius of curvature of the fifth lens is in the range of (-456) to (-451) mm, the tenth radius of curvature of the fifth lens is in the range of (-120) to (-115) mm; the eleventh radius of curvature of the sixth lens is in the range of 368 to 373 mm, and the twelfth radius of curvature of the sixth lens is in the range of (-648) to (-642) mm.

[0007] In some embodiments, the center thickness of the first lens is in the range of 9 to 13 mm, the center thickness of the second lens is in the range of 4 to 6 mm, the center thickness of the third lens is in the range of 11 to 15 mm, the center thickness of the fourth lens is in the range of 7 to 9 mm, the center thickness of the fifth lens is in the range of 23 to 27 mm, the center thickness of the sixth lens is in the range of 50 to 55 mm, and the center thickness of the seventh lens is in the range of 13 to 15 mm.

[0008] In some embodiments, the distance between the center of the first lens and the center of the second lens is in the range of 35-45 mm, the distance between the center of the second lens and the center of the third lens is in the range of 17-23 mm, the distance between the center of the third lens and the center of the fourth lens is in the range of 35-40 mm, the distance between the center of the fourth lens and the center of the fifth lens is in the range of 2-4 mm, the distance between the center of the fifth lens and the center of the sixth lens is in the range of 140-148 mm, and the distance between the center of the sixth lens and the center of the seventh lens is in the range of 5-7 mm.

[0009] In some embodiments, the ratio of the refractive index to the Abbe number of the first lens is in the range of 0.021 to 0.022, the ratio of the refractive index to the Abbe number of the second lens is in the range of 0.033 to 0.034, the ratio of the refractive index to the Abbe number of the third lens is in the range of 0.021 to 0.022, the ratio of the refractive index to the Abbe number of the fourth lens is in the range of 0.014 to 0.016, the ratio of the refractive index to the Abbe number of the fifth lens is in the range of 0.021 to 0.022, the ratio of the refractive index to the Abbe number of the sixth lens is in the range of 0.021 to 0.022, and the ratio of the refractive index to the Abbe number of the seventh lens is in the range of 0.021 to 0.022.

[0010] In some embodiments, the sagittal field curvature of the optical lens is less than or equal to 1.2 mm, and the meridional field curvature of the optical lens is less than or equal to 0.46 mm.

[0011] In some embodiments, the maximum distortion of the optical lens is less than or equal to 0.38%, and the image-side telecentricity of the optical lens is less than 2.5°.

[0012] In some embodiments, the scanning angle of the optical lens is 16.7°, and the scanning area of ​​the optical lens is 185mm × 185mm.

[0013] In some embodiments, the focal length of the optical lens is in the range of 440 to 450 mm, and the working distance of the optical lens is in the range of 218 to 223 mm.

[0014] This specification provides a laser processing system according to one or more embodiments, including a laser, a scanning galvanometer, and an optical lens for laser processing, wherein the optical lens is the optical lens described in any embodiment, and the center wavelength of the laser is 343 nm. Attached Figure Description

[0015] This specification will be further described by way of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting; in these embodiments, the same reference numerals denote the same structures, wherein:

[0016] Figure 1 These are schematic diagrams of the optical lens structure shown in some embodiments of this specification;

[0017] Figure 2 This is a schematic diagram of the optical path of an optical lens according to some embodiments of this specification;

[0018] Figure 3 These are field curvature diagrams of optical lenses shown in some embodiments of this specification;

[0019] Figure 4 These are distortion analysis diagrams of optical lenses shown in some embodiments of this specification. Detailed Implementation

[0020] To more clearly illustrate the technical solutions of the embodiments in this specification, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this specification. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0021] It should be understood that the terms “system,” “device,” “unit,” and / or “module” used herein are one way to distinguish different components, elements, parts, sections, or assemblies at different levels. However, if other terms can achieve the same purpose, they may be replaced by other expressions.

[0022] As indicated in this specification and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" do not specifically refer to the singular and may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0023] Figure 1 This is a schematic diagram of the structure of an optical lens according to some embodiments of this specification.

[0024] This specification provides an optical lens through some embodiments. In some embodiments, such as Figure 1 As shown, along the laser incident direction, the optical lens sequentially includes a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, and a seventh lens 7.

[0025] In some embodiments, the first lens 1 is a biconvex lens, with its center thickness greater than its edge thickness. In some embodiments, both surfaces of the first lens 1 are convex, that is, both surfaces of the first lens 1 bulge outwards.

[0026] Optical power is a physical quantity that describes the ability of a lens or optical system to converge or diverge light rays. Optical power characterizes the refractive power of a lens or optical system for an incident parallel beam of light; the higher the optical power value, the more strongly the parallel beam is refracted. When the optical power is greater than 0, it indicates that the incident parallel beam converges upon exiting; when the optical power is less than 0, it indicates that the incident parallel beam diverges upon exiting; when the optical power is equal to 0, it indicates that the incident parallel beam remains parallel upon exiting.

[0027] In some embodiments, the first lens 1 has positive optical power, that is, the optical power of the first lens 1 is greater than 0, which means that the parallel light beam incident on the first lens 1 converges when exiting the first lens 1.

[0028] By setting the first lens as a biconvex lens, its convex surface provides a strong converging effect, which helps in the final imaging. The first lens has positive optical power, further converging the light rays, which is beneficial for improving the light-gathering ability at the edge of the field of view. Increasing the relative illumination at the edge of the field of view can initially reduce the aperture of the incident beam. In other words, by setting the first lens to have positive optical power, the converging effect is further enhanced, which helps control the beam size in subsequent optical paths.

[0029] In some embodiments, the second lens 2 is a biconcave lens, with its center thickness being less than its edge thickness. In some embodiments, both surfaces of the second lens 2 are concave, meaning both surfaces of the second lens 2 are recessed towards the interior of the second lens 2.

[0030] In some embodiments, the second lens 2 has a negative optical power, that is, the optical power of the second lens 2 is less than 0, which means that the parallel light beam incident on the second lens 2 diverges when exiting the second lens 2.

[0031] By setting the second lens to have a negative optical power, thus enabling it to diverge, the range of light entering the lens can be increased. Using a second lens with a negative optical power after a first lens with a positive optical power helps with chromatic aberration correction, especially in the ultraviolet band, where the correction effect is particularly good.

[0032] In some embodiments, the third lens 3 is a meniscus lens, with one side near the fourth lens 4 being convex, the convex direction being consistent with the laser incident direction; the other side is concave, recessed towards the interior of the third lens 3. In some embodiments, the third lens 3 has positive optical power.

[0033] The convex surface of the meniscus lens has a converging effect, which can initially reduce the aperture of the incident beam. The third lens has positive optical power, further enhancing the converging effect and helping to control the beam size in subsequent optical paths.

[0034] In some embodiments, the fourth lens 4 is a meniscus lens, with one side near the fifth lens 5 being convex, the convex surface oriented in the same direction as the laser incident direction, and the other side being concave, recessed towards the interior of the fourth lens 4. The fourth lens 4 has positive optical power. The characteristics of the fourth lens 4 are similar to those of the third lens 3, and will not be described again.

[0035] In some embodiments, the fifth lens 5 is a meniscus lens, with the side closest to the sixth lens 6 being convex, the convex direction being consistent with the laser incident direction, and the fifth lens 5 having positive optical power. The characteristics of the fifth lens 5 are similar to those of the third lens 3 and the fourth lens 4, and will not be described again.

[0036] The third, fourth, and fifth lenses are all meniscus lenses with positive optical power, which can further converge light rays and make the light entering subsequent lenses smoother. The combination of multiple lenses with positive optical power is beneficial for reducing the beam aperture.

[0037] In some embodiments, the sixth lens 6 is a biconvex lens, and the characteristics of the sixth lens 1 are similar to those of the first lens 1, which will not be described again.

[0038] By setting the sixth lens as a biconvex lens, a strong converging effect can be provided, which helps in the final imaging. The sixth lens with positive optical power can further converge light rays, which is beneficial to improving the light convergence ability of the edge field of view and enhancing the relative illumination of the edge field of view.

[0039] In some embodiments, the seventh lens 7 is a protective plate. In some embodiments, the seventh lens 7 can be a plane lens, that is, both sides of the seventh lens 7 are planes.

[0040] The seventh lens can act as a sealed window to maintain the internal environment of the optical system. By using a seventh lens, subsequent optical components or detectors can be protected from environmental contamination and mechanical damage. Furthermore, a planar seventh lens can provide additional optical thickness without altering the optical path, facilitating fine-tuning of the focal length and image plane position.

[0041] In some embodiments, the lenses can be made of materials such as fused silica, calcium fluoride, magnesium fluoride, silicon, germanium, zinc selenide, and various optical colorless glasses. After the lenses are manufactured, they can be coated using a vacuum coating process as needed. For example, an anti-reflective coating can be deposited on the lens surface to reduce reflections, thereby reducing light energy loss and making the image clearer.

[0042] The radius of curvature is used to describe the degree of curvature of a curve. The radius of curvature is the reciprocal of the curvature.

[0043] In some embodiments, the first radius of curvature of the first lens 1 is in the range of 90 to 95 mm, and the second radius of curvature of the first lens 1 is in the range of (-355) to (-350) mm. In some embodiments, the first radius of curvature of the first lens 1 is in the range of 91 to 93 mm, and the second radius of curvature of the first lens 1 is in the range of (-353) to (-351) mm. In some embodiments, the first radius of curvature of the first lens 1 is in the range of 92.71 to 92.85 mm, and the second radius of curvature of the first lens 1 is in the range of (-352.55) to (-352.39) mm. In some embodiments, the first radius of curvature of the first lens 1 is 92.78 ± 0.01 mm, and the second radius of curvature of the first lens 1 is (-352.49 ± 0.01) mm.

[0044] It should be understood that, in this specification, the two radii of curvature of the lens are the radius of curvature of the laser incident surface and the radius of curvature of the laser exit surface of the lens, respectively. For example, the first radius of curvature of the first lens 1 corresponds to the radius of curvature of the laser incident surface of the first lens 1, and the second radius of curvature corresponds to the radius of curvature of the laser exit surface of the first lens 1.

[0045] In some embodiments, the third radius of curvature of the second lens 2 is in the range of (-108) to (-102) mm, and the fourth radius of curvature of the second lens 2 is in the range of 118 to 125 mm. In some embodiments, the third radius of curvature of the second lens 2 is in the range of (-106) to (-104) mm, and the fourth radius of curvature of the second lens 2 is in the range of 120 to 123 mm. In some embodiments, the third radius of curvature of the second lens 2 is in the range of (-105.39) to (-105.09) mm, and the fourth radius of curvature of the second lens 2 is in the range of 121.81 to 121.99 mm. In some embodiments, the third radius of curvature of the second lens 2 is (-105.22 ± 0.01) mm, and the fourth radius of curvature of the second lens 2 is 121.9 ± 0.01 mm. The third radius of curvature corresponds to the radius of curvature of the laser incident surface of the second lens 2 (i.e., the side closer to the first lens 1), and the fourth radius of curvature corresponds to the radius of curvature of the laser exit surface of the second lens 2 (i.e., the side farther away from the first lens 1).

[0046] In some embodiments, the fifth radius of curvature of the third lens 3 is in the range of (-143) to (-138) mm, and the sixth radius of curvature of the third lens 3 is in the range of (-84) to (-79) mm. In some embodiments, the fifth radius of curvature of the third lens 3 is in the range of (-142) to (-141) mm, and the sixth radius of curvature of the third lens 3 is in the range of (-82) to (-81) mm. In some embodiments, the fifth radius of curvature of the third lens 3 is in the range of (-141.55) to (-141.77) mm, and the sixth radius of curvature of the third lens 3 is in the range of (-81.88) to (-81.55) mm. In some embodiments, the fifth radius of curvature of the third lens 3 is (-141.66 ± 0.01) mm, and the sixth radius of curvature of the third lens 3 is (-81.68 ± 0.01) mm. The fifth radius of curvature corresponds to the radius of curvature of the laser incident surface of the third lens 3, and the sixth radius of curvature corresponds to the radius of curvature of the laser exit surface of the third lens 3.

[0047] In some embodiments, the seventh radius of curvature of the fourth lens 4 is in the range of (-84) to (-79) mm, and the eighth radius of curvature of the fourth lens 4 is in the range of (-194) to (-189) mm. In some embodiments, the seventh radius of curvature of the fourth lens 4 is in the range of (-82) to (-81) mm, and the eighth radius of curvature of the fourth lens 4 is in the range of (-193) to (-191) mm. In some embodiments, the seventh radius of curvature of the fourth lens 4 is in the range of (-81.65) to (-81.45) mm, and the eighth radius of curvature of the fourth lens 4 is in the range of (-191.99) to (-191.81) mm. In some embodiments, the seventh radius of curvature of the fourth lens 4 is (-81.54 ± 0.01) mm, and the eighth radius of curvature of the fourth lens 4 is (-191.91 ± 0.01) mm. Among them, the seventh radius of curvature corresponds to the radius of curvature of the laser incident surface of the fourth lens 4, and the eighth radius of curvature corresponds to the radius of curvature of the laser exit surface of the fourth lens 4.

[0048] In some embodiments, the ninth radius of curvature of the fifth lens 5 is in the range of (-456) to (-451) mm, and the tenth radius of curvature of the fifth lens 5 is in the range of (-120) to (-115) mm. In some embodiments, the ninth radius of curvature of the fifth lens 5 is in the range of (-455) to (-454) mm, and the tenth radius of curvature of the fifth lens 5 is in the range of (-119) to (-118) mm. In some embodiments, the ninth radius of curvature of the fifth lens 5 is in the range of (-454.65) to (-454.41) mm, and the tenth radius of curvature of the fifth lens 5 is in the range of (-118.37) to (-118.20) mm. In some embodiments, the ninth radius of curvature of the fifth lens 5 is (-454.54 ± 0.01) mm, and the tenth radius of curvature of the fifth lens 5 is (-118.27 ± 0.01) mm. Among them, the ninth radius of curvature corresponds to the radius of curvature of the laser incident surface of the fifth lens 5 (i.e., the side closer to the fourth lens 4), and the tenth radius of curvature corresponds to the radius of curvature of the laser exit surface of the fifth lens 5 (i.e., the side farther away from the fourth lens 4).

[0049] In some embodiments, the eleventh radius of curvature of the sixth lens 6 is in the range of 368–373 mm, and the twelfth radius of curvature of the sixth lens 6 is in the range of (-648)–(-642) mm. In some embodiments, the eleventh radius of curvature of the sixth lens 6 is in the range of 370–371 mm, and the twelfth radius of curvature of the sixth lens 6 is in the range of (-646)–(-645) mm. In some embodiments, the eleventh radius of curvature of the sixth lens 6 is in the range of 370.28–370.45 mm, and the twelfth radius of curvature of the sixth lens 6 is in the range of (-645.27)–(-645.01) mm. In some embodiments, the eleventh radius of curvature of the sixth lens 6 is 370.36 ± 0.01 mm, and the twelfth radius of curvature of the sixth lens 6 is (-645.16 ± 0.01) mm. Among them, the eleventh radius of curvature corresponds to the radius of curvature of the laser incident surface of the sixth lens 6 (i.e., the side closer to the fifth lens 5), and the twelfth radius of curvature corresponds to the radius of curvature of the laser exit surface of the sixth lens 6 (i.e., the side farther away from the fifth lens 5).

[0050] By setting an appropriate radius of curvature, the focal length of each lens can be precisely controlled to meet the needs of different application scenarios, thereby reducing field curvature and distortion.

[0051] In some embodiments, the center thickness of the first lens 1 is in the range of 9–13 mm, the center thickness of the second lens 2 is in the range of 4–6 mm, the center thickness of the third lens 3 is in the range of 11–15 mm, the center thickness of the fourth lens 4 is in the range of 7–9 mm, the center thickness of the fifth lens 5 is in the range of 23–27 mm, the center thickness of the sixth lens 6 is in the range of 50–55 mm, and the center thickness of the seventh lens 7 is in the range of 13–15 mm. In some embodiments, the center thickness of the first lens 1 is in the range of 10–12 mm, the center thickness of the second lens 2 is in the range of 4.5–5.5 mm, the center thickness of the third lens 3 is in the range of 12–13 mm, the center thickness of the fourth lens 4 is in the range of 7.5–8.5 mm, the center thickness of the fifth lens 5 is in the range of 25–26 mm, the center thickness of the sixth lens 6 is in the range of 52–53 mm, and the center thickness of the seventh lens 7 is in the range of 13.5–14.5 mm. In some embodiments, the center thickness of the first lens 1 is 11±0.1mm, the center thickness of the second lens 2 is 5±0.1mm, the center thickness of the third lens 3 is 12.91±0.1mm, the center thickness of the fourth lens 4 is 8±0.1mm, the center thickness of the fifth lens 5 is 25.87±0.1mm, the center thickness of the sixth lens 6 is 52.23±0.1mm, and the center thickness of the seventh lens 7 is 14±0.1mm.

[0052] Since different wavelengths of light refract at greater angles when passing through thicker materials, lenses with a larger center thickness usually produce greater chromatic aberration. By limiting the center thickness of the lens, each lens can be set to an appropriate thickness, thereby reducing dispersion.

[0053] In some embodiments, the distance between the center of the first lens 1 and the center of the second lens 2 is in the range of 35-45 mm, the distance between the center of the second lens 2 and the center of the third lens 3 is in the range of 17-23 mm, the distance between the center of the third lens 3 and the center of the fourth lens 4 is in the range of 35-40 mm, the distance between the center of the fourth lens 4 and the center of the fifth lens 5 is in the range of 2-4 mm, the distance between the center of the fifth lens 5 and the center of the sixth lens 6 is in the range of 140-148 mm, and the distance between the center of the sixth lens 6 and the center of the seventh lens 7 is in the range of 5-7 mm. In some embodiments, the distance between the center of the first lens 1 and the center of the second lens 2 is in the range of 39-41 mm, the distance between the center of the second lens 2 and the center of the third lens 3 is in the range of 20-21 mm, the distance between the center of the third lens 3 and the center of the fourth lens 4 is in the range of 37-38 mm, the distance between the center of the fourth lens 4 and the center of the fifth lens 5 is in the range of 2.5-3.5 mm, the distance between the center of the fifth lens 5 and the center of the sixth lens 6 is in the range of 144-145 mm, and the distance between the center of the sixth lens 6 and the center of the seventh lens 7 is in the range of 5.5-6.5 mm. In some embodiments, the distance between the center of the first lens 1 and the center of the second lens 2 is within the range of 40±0.1mm, the distance between the center of the second lens 2 and the center of the third lens 3 is within the range of 20.22±0.1mm, the distance between the center of the third lens 3 and the center of the fourth lens 4 is within the range of 37.12±0.1mm, the distance between the center of the fourth lens 4 and the center of the fifth lens 5 is within the range of 3±0.1mm, the distance between the center of the fifth lens 5 and the center of the sixth lens 6 is within the range of 144.66±0.1mm, and the distance between the center of the sixth lens 6 and the center of the seventh lens 7 is within the range of 6±0.1mm.

[0054] The spacing between lenses affects the system's resolution. Excessive spacing can lead to longer light paths, increasing aberrations; while insufficient spacing can prevent light from converging properly, also affecting resolution. Some embodiments in this specification optimize lens spacing to maintain good contrast transmission at different spatial frequencies, thereby improving system resolution.

[0055] The spacing between lenses affects the contrast transmission capability of the system. Some embodiments in this specification ensure good contrast as light propagates between lenses by setting appropriate spacing between adjacent lenses, thus avoiding contrast loss due to excessive scattering or reflection.

[0056] Chromatic aberration (dispersion) occurs because light of different wavelengths refracts at different angles when passing through a lens, causing different colors of light to focus at different positions. The Abbe number, also known as the dispersion coefficient, is used to measure the degree of light dispersion in a transparent medium.

[0057] Figure 2This is a schematic diagram of the optical path of an optical lens according to some embodiments of this specification. In some embodiments, by limiting the ratio of the refractive index to the Abbe number of the optical lens, light of different wavelengths is focused onto the same plane as much as possible, such as... Figure 2 As shown, this reduces chromatic aberration; it not only helps reduce aberrations (such as spherical aberration, coma, astigmatism, etc.), but also improves the overall imaging quality and resolution of the system; it ensures that the focal plane of the entire optical system is more uniform, avoiding focus shift caused by chromatic aberration differences between different lenses, thereby improving the consistency and sharpness of the image.

[0058] In some embodiments, the ratio of the refractive index to the Abbe number of the first lens 1 is in the range of 0.021 to 0.022, the ratio of the refractive index to the Abbe number of the second lens 2 is in the range of 0.033 to 0.034, the ratio of the refractive index to the Abbe number of the third lens 3 is in the range of 0.021 to 0.022, the ratio of the refractive index to the Abbe number of the fourth lens 4 is in the range of 0.014 to 0.016, the ratio of the refractive index to the Abbe number of the fifth lens 5 is in the range of 0.021 to 0.022, the ratio of the refractive index to the Abbe number of the sixth lens 6 is in the range of 0.021 to 0.022, and the ratio of the refractive index to the Abbe number of the seventh lens 7 is in the range of 0.021 to 0.022. In some embodiments, the ratio of the refractive index to the Abbe number of the first lens 1 is 1.45846 / 67.82, the ratio of the refractive index to the Abbe number of the second lens 2 is 1.54814 / 45.75, the ratio of the refractive index to the Abbe number of the third lens 3 is 1.45846 / 67.82, the ratio of the refractive index to the Abbe number of the fourth lens 4 is 1.45846 / 67.82, the ratio of the refractive index to the Abbe number of the fifth lens 5 is 1.45846 / 67.82, the ratio of the refractive index to the Abbe number of the sixth lens 6 is 1.45846 / 67.82, and the ratio of the refractive index to the Abbe number of the seventh lens 7 is 1.45846 / 67.82.

[0059] By limiting the ratio of refractive index to Abbe number within the aforementioned range, the design of optical systems can be simplified, the number and complexity of lenses can be reduced, thereby lowering costs and improving system reliability.

[0060] In some embodiments, the focal length of the optical lens designed according to the above embodiments is in the range of 440 to 450 mm, and the working distance of the optical lens is in the range of 218 to 223 mm. In some embodiments, the focal length of the optical lens is 445 mm, and the working distance of the optical lens is 220.75 ± 0.1 mm. The working distance refers to the distance between the side of the seventh lens 7 away from the sixth lens 6 and the focal point of the light beam.

[0061] By setting an appropriate focal length, one can determine the appropriate magnification and field of view.

[0062] In some embodiments, the scanning angle of the optical lens designed according to the above embodiments is 16.7°, and the scanning area of ​​the optical lens is 185mm×185mm.

[0063] The scanning angle refers to the maximum angular range of the laser beam deflection. The scanning area refers to the region on the target plane that the laser beam can cover after deflection. By limiting the large scanning angle and the large scanning area, the laser can cover a predetermined, larger processing area.

[0064] Figure 3 This is a field curvature diagram of an optical lens according to some embodiments of this specification, corresponding to F-theta distortion. The horizontal axis represents field curvature in millimeters; the vertical axis represents the scanning angle in degrees.

[0065] In some embodiments, the sagittal field curvature of the optical lens designed according to the above embodiments is less than or equal to 1.2 mm, and the meridional field curvature of the optical lens designed according to the above embodiments is less than or equal to 0.46 mm.

[0066] Sagittal curvature refers to the curvature along the bowstring direction (perpendicular to the meridional plane), reflecting the lateral focusing characteristics of light rays. The sagittal plane is the plane passing through the principal ray and perpendicular to the meridional plane. The curvature in the sagittal direction affects the focal point and shape of the image.

[0067] Meridional curvature refers to the curvature along the meridional plane, that is, the plane perpendicular to the optical axis, reflecting the focusing ability of light rays along the meridional direction. The meridional plane is the plane determined by the principal ray and the optical axis. The curvature along the meridional direction affects the position and shape of the focal plane.

[0068] By limiting the sagittal and meridional field curvatures, image blur can be reduced, resulting in clearer imaging.

[0069] Figure 4 This is a distortion analysis diagram of an optical lens according to some embodiments of this specification. The corresponding distortion type is F-theta distortion. The horizontal axis represents the relative F-theta distortion, in percentage (%); the vertical axis represents the scanning angle, in degrees (°).

[0070] In some embodiments, such as Figure 4 As shown, the maximum distortion of the optical lens designed according to the above embodiment is less than or equal to 0.38%, that is, the maximum F-theta relative distortion of the optical lens is less than or equal to 0.38%.

[0071] In some embodiments, the image-side telecentricity of the optical lens designed according to the above embodiments is less than 2.5°.

[0072] Telecentrism describes the angle by which the principal ray deviates from the optical axis. Object-side telecentrism is defined by the position of the incident pupil within the object space, while image-side telecentrism can be defined by the exiting pupil located at infinity within the object space.

[0073] The optical lenses of some embodiments in this specification achieve low distortion and small image telecentricity.

[0074] This specification provides a laser processing system in some embodiments, including a laser, a scanning galvanometer, and an optical lens for laser processing.

[0075] A laser is a device that emits laser light. Examples of lasers include gas lasers, solid-state lasers, semiconductor lasers, and dye lasers.

[0076] The scanning galvanometer is an optical path scanning device that can be applied to laser scanning, laser pattern display, etc.

[0077] The optical lens is any of the optical lenses described in the foregoing embodiments, and will not be described again.

[0078] In some embodiments, the center wavelength of the laser is 343 nm. The center wavelength refers to the center position of the wavelength distribution of the laser output.

[0079] The laser processing system described in some embodiments of this specification uses the 343nm ultraviolet band, which has a shorter wavelength and higher energy, and is widely used in applications such as scanning marking, drilling, and edge trimming. By employing an optical lens with low field curvature and low distortion, the chromatic aberration problem of ultraviolet band lenses is effectively solved, resulting in clearer images.

[0080] The basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this specification. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this specification. Such modifications, improvements, and corrections are suggested in this specification and therefore remain within the spirit and scope of the exemplary embodiments described herein.

[0081] Furthermore, this specification uses specific terms to describe embodiments thereof. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of this specification. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Moreover, certain features, structures, or characteristics in one or more embodiments of this specification can be appropriately combined.

[0082] Furthermore, unless expressly stated in the claims, the order of processing elements and sequences, the use of numbers and letters, or other names described in this specification are not intended to limit the order of the processes and methods described herein. Although various examples have been discussed in the foregoing disclosure of embodiments that are currently considered useful, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments; rather, the claims are intended to cover all modifications and equivalent combinations that conform to the substance and scope of the embodiments described herein. For example, while the system components described above can be implemented using hardware devices, they can also be implemented solely using software solutions, such as installing the described system on existing servers or mobile devices.

[0083] Similarly, it should be noted that, in order to simplify the descriptions disclosed herein and thus aid in the understanding of one or more embodiments, the foregoing description of embodiments in this specification sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this method of disclosure does not imply that the subject matter of this specification requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0084] For each patent, patent application, patent application publication, and other material, such as articles, books, specifications, publications, and documents, referenced in this specification, the entire contents of which are incorporated herein by reference. This excludes historical application documents that are inconsistent with or conflict with the content of this specification, as well as documents that limit the broadest scope of the claims in this specification (currently or subsequently appended to this specification). It should be noted that in the event of any inconsistency or conflict between the descriptions, definitions, and / or terminology used in the supplementary materials to this specification and the content of this specification, the descriptions, definitions, and / or terminology used in this specification shall prevail.

[0085] Finally, it should be understood that the embodiments described in this specification are merely illustrative of the principles of the embodiments described herein. Other variations may also fall within the scope of this specification. Therefore, alternative configurations of the embodiments described herein are intended to be illustrative rather than limiting, and should be considered consistent with the teachings of this specification. Accordingly, the embodiments described herein are not limited to those explicitly introduced and described herein.

Claims

1. An optical lens, characterized in that, Along the laser incident direction, the lens consists of, in sequence: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens; The first lens is a biconvex lens; The second lens is a biconcave lens; The third lens is a meniscus lens, with its convex surface aligned with the laser incident direction. The fourth lens is a meniscus lens, with its convex surface aligned with the laser incident direction. The fifth lens is a meniscus lens, with its convex surface aligned with the laser incident direction. The sixth lens is a biconvex lens; The seventh lens is a protective plate.

2. The optical lens as described in claim 1, characterized in that, The first radius of curvature of the first lens is in the range of 90 to 95 mm, and the second radius of curvature of the first lens is in the range of (-355) to (-350) mm; The third radius of curvature of the second lens is in the range of (-108) to (-102) mm, and the fourth radius of curvature of the second lens is in the range of 118 to 125 mm; The fifth radius of curvature of the third lens is in the range of (-143) to (-138) mm, and the sixth radius of curvature of the third lens is in the range of (-84) to (-79) mm; The seventh radius of curvature of the fourth lens is in the range of (-84) to (-79) mm, and the eighth radius of curvature of the fourth lens is in the range of (-194) to (-189) mm; The ninth radius of curvature of the fifth lens is in the range of (-456) to (-451) mm, and the tenth radius of curvature of the fifth lens is in the range of (-120) to (-115) mm. The eleventh radius of curvature of the sixth lens is in the range of 368 to 373 mm, and the twelfth radius of curvature of the sixth lens is in the range of (-648) to (-642) mm.

3. The optical lens as described in claim 1, characterized in that, The center thickness of the first lens is in the range of 9 to 13 mm, the center thickness of the second lens is in the range of 4 to 6 mm, the center thickness of the third lens is in the range of 11 to 15 mm, the center thickness of the fourth lens is in the range of 7 to 9 mm, the center thickness of the fifth lens is in the range of 23 to 27 mm, the center thickness of the sixth lens is in the range of 50 to 55 mm, and the center thickness of the seventh lens is in the range of 13 to 15 mm.

4. The optical lens as described in claim 1, characterized in that, The distance between the center of the first lens and the center of the second lens is in the range of 35-45mm, the distance between the center of the second lens and the center of the third lens is in the range of 17-23mm, the distance between the center of the third lens and the center of the fourth lens is in the range of 35-40mm, the distance between the center of the fourth lens and the center of the fifth lens is in the range of 2-4mm, the distance between the center of the fifth lens and the center of the sixth lens is in the range of 140-148mm, and the distance between the center of the sixth lens and the center of the seventh lens is in the range of 5-7mm.

5. The optical lens as described in claim 1, characterized in that, The ratio of the refractive index to the Abbe number of the first lens is in the range of 0.021 to 0.022; the ratio of the refractive index to the Abbe number of the second lens is in the range of 0.033 to 0.034; the ratio of the refractive index to the Abbe number of the third lens is in the range of 0.021 to 0.022; the ratio of the refractive index to the Abbe number of the fourth lens is in the range of 0.014 to 0.016; the ratio of the refractive index to the Abbe number of the fifth lens is in the range of 0.021 to 0.022; the ratio of the refractive index to the Abbe number of the sixth lens is in the range of 0.021 to 0.022; and the ratio of the refractive index to the Abbe number of the seventh lens is in the range of 0.021 to 0.

022.

6. The optical lens according to any one of claims 1-5, characterized in that, The sagittal field curvature of the optical lens is less than or equal to 1.2 mm, and the meridional field curvature of the optical lens is less than or equal to 0.46 mm.

7. The optical lens according to any one of claims 1-5, characterized in that, The maximum distortion of the optical lens is less than or equal to 0.38%, and the image-side telecentricity of the optical lens is less than 2.5°.

8. The optical lens according to any one of claims 1-5, characterized in that, The scanning angle of the optical lens is 16.7°, and the scanning area of ​​the optical lens is 185mm×185mm.

9. The optical lens according to any one of claims 1-5, characterized in that, The focal length of the optical lens is in the range of 440 to 450 mm, and the working distance of the optical lens is in the range of 218 to 223 mm.

10. A laser processing system, characterized in that, It includes a laser, a scanning galvanometer, and an optical lens for laser processing, wherein the optical lens is the optical lens according to any one of claims 1-9, and the center wavelength of the laser is 343 nm.

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