Large-breadth ultraviolet telecentric field lens

Abstract

The utility model belongs to the technical field of optics, and discloses a large-breadth ultraviolet telecentric field lens, which sequentially comprises a first lens, a second lens, a third lens, a fourth lens and a protective lens from the laser incidence direction, the first lens is a negative-focal-power lens of a meniscus structure, the second lens and the third lens are positive-focal-power lenses of meniscus structures respectively, the fourth lens is a positive-focal-power lens of a biconvex structure, and the protective lens is of a flat plate structure. The concave surfaces of the first lens, the second lens and the third lens face the laser incidence direction. Therefore, the first lens, the second lens, the third lens and the fourth lens form a negative-positive-positive-positive lens sequence, the scanning range of the whole large-format ultraviolet telecentric field lens can reach 250 mm * 250 mm, the number of times of movement of products in the machining process is effectively reduced, the overall machining speed is increased, the machining time is remarkably shortened, and the production efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the field of optical technology, and in particular to a large-format ultraviolet telecentric field mirror. Background Technology

[0002] Telecentric field lenses generally refer to telecentric F-theta lenses. In a scanning system, the incident angle of the laser is controlled by the deflection of a motor in the galvanometer. The telecentric field lens focuses the laser onto the same processing area. The telecentric F-theta lens eliminates optical system aberrations through a combination of multiple lenses, and can focus lasers with different deflection angles onto different materials to draw different patterns, realizing engraving images, drilling, cutting, or other applications. For example, the telecentric field lens with ultra-long focal depth and large scanning area disclosed in patent document "CN 208937802 U" makes the marking clearer and the depth can meet the requirements by using a first lens, a second lens, and a third lens with negative positive and positive focal lengths in sequence. However, the scanning area is small. Therefore, when this telecentric field lens is applied to a copper foil drilling machine for scanning, it cannot meet the requirements for the production of existing copper foil products with a length and width of 500mm. This results in multiple moves required to process a complete product, which prolongs the processing time and reduces production efficiency. Utility Model Content

[0003] The main objective of this invention is to provide a large-format ultraviolet telecentric field microscope, which aims to solve the technical problem that existing telecentric field microscopes have a small scanning area, requiring multiple moves to process a complete product, thus prolonging the processing time and resulting in low production efficiency.

[0004] In order to achieve the above-mentioned utility model objectives, this utility model proposes a large-format ultraviolet telecentric field mirror, which, starting from the laser incident direction, sequentially includes a first lens, a second lens, a third lens, a fourth lens, and a protective mirror.

[0005] The first lens is a negative power lens with a meniscus structure, the second lens and the third lens are positive power lenses with meniscus structures, the fourth lens is a positive power lens with a biconvex structure, and the protective lens is a flat plate structure. The concave surfaces of the first lens, the second lens and the third lens face the laser incident direction.

[0006] Furthermore, the large-format ultraviolet telecentric field mirror also includes an entrance pupil plane and an image plane;

[0007] The entrance pupil surface is disposed on the side of the first lens away from the second lens, and the image plane is disposed on the side of the protective lens away from the fourth lens. The first interval between the entrance pupil surface and the first lens is 110 mm, the second interval between the first lens and the second lens is 22.5 mm, the third interval between the second lens and the third lens is 14.6 mm, the fourth interval between the third lens and the fourth lens is 68.9 mm, the fifth interval between the fourth lens and the protective lens is 6.5 mm, and the sixth interval between the image plane and the protective lens is 570 mm.

[0008] Furthermore, the radii of curvature on the front and rear sides of the first lens are -87.56 mm and -1134.11 mm, respectively, and the thickness of the first center of the first lens is 20.2 mm.

[0009] Furthermore, the radii of curvature on the front and rear sides of the second lens are -393.1 mm and -152.9 mm, respectively, and the thickness of the second center of the second lens is 39.5 mm.

[0010] Furthermore, the radii of curvature on the front and rear sides of the third lens are -1771.1 mm and -223.6 mm, respectively, and the thickness of the third center of the third lens is 45 mm.

[0011] Furthermore, the radii of curvature on the front and rear sides of the fourth lens are 822.4 mm and -664.2 mm, respectively, and the thickness of the fourth center of the fourth lens is 45 mm.

[0012] Furthermore, the fifth center thickness of the protective mirror is 10 mm.

[0013] Furthermore, the total focal length of the large-format ultraviolet telecentric lens is f, and the focal lengths of the first lens, the second lens, the third lens, and the fourth lens are f1, f2, f3, and f4, respectively, wherein the total focal length f of the large-format ultraviolet telecentric lens satisfies the following relationship: -0.75 <f1 / f<-0.35,0.9<f2 / f<1.4,1.1<f3 / f<1.6,1.6<f4 / f<2.2。

[0014] Furthermore, the first lens, the second lens, the third lens, the fourth lens, and the protective mirror are all made of fused silica glass and have a refractive index Nd of 1.46.

[0015] Furthermore, the entire large-format ultraviolet telecentric field lens has a focal length of 420mm, a wavelength of 355nm, a telecentricity of 3.4°, an optical scanning angle of ±25°, an incident beam diameter of 16mm, and a scanning range of 250mm*250mm.

[0016] Beneficial effects:

[0017] This utility model discloses a large-format ultraviolet telecentric field lens, which, starting from the laser incident direction, sequentially includes a first lens, a second lens, a third lens, a fourth lens, and a protective mirror. The first lens is a meniscus negative power lens, the second and third lenses are meniscus positive power lenses, the fourth lens is a biconvex positive power lens, and the protective mirror is a flat plate structure. The concave surfaces of the first, second, and third lenses face the laser incident direction. Therefore, by forming a "negative-positive-positive-positive" lens sequence with the first, second, third, and fourth lenses, the scanning range of the entire large-format ultraviolet telecentric field lens can reach 250mm*250mm. This effectively reduces the number of times the product needs to be moved during processing, avoids the need for repositioning and adjusting processing parameters after each product movement, makes the processing process more continuous and smooth, accelerates the overall processing speed, significantly shortens processing time, and improves production efficiency. Attached Figure Description

[0018] Figure 1 This is an optical path diagram of a large-format ultraviolet telecentric field mirror according to an embodiment of the present invention;

[0019] Figure 2 This is a field curvature and F-theta distortion diagram of a large-format ultraviolet telecentric field microscope according to an embodiment of the present invention;

[0020] Figure 3 This is a dot plot of a large-format ultraviolet telecentric field microscope according to an embodiment of the present invention;

[0021] Figure 4 This is the optical transfer function (MTF) plot of a large-format ultraviolet telecentric field mirror according to an embodiment of the present invention.

[0022] in:

[0023] G1, First lens; G2, Second lens; G3, Third lens; G4, Fourth lens; SG, Protective lens;

[0024] d0, first interval; d2, second interval; d4, third interval; d6, fourth interval; d8, fifth interval; d10, sixth interval;

[0025] d1, first center thickness; d3, second center thickness; d5, third center thickness; d7, fourth center thickness; d9, fifth center thickness.

[0026] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0027] It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0028] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly and specifically defined.

[0029] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0030] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0031] Reference Figures 1-4 This embodiment provides a large-format ultraviolet telecentric field mirror, which, starting from the laser incident direction, sequentially includes a first lens G1, a second lens G2, a third lens G3, a fourth lens G4, and a protective mirror SG;

[0032] The first lens G1 is a negative power lens with a meniscus structure, the second lens G2 and the third lens G3 are positive power lenses with meniscus structures, the fourth lens G4 is a positive power lens with a biconvex structure, and the protective mirror SG is a flat plate structure. The concave surfaces of the first lens G1, the second lens G2 and the third lens G3 are respectively oriented towards the laser incident direction.

[0033] In the above embodiment, the large-format ultraviolet telecentric field lens includes a first lens G1, a second lens G2, a third lens G3, a fourth lens G4, and a window plate arranged sequentially along the incident direction of light. The first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the protective lens SG are preferably made of fused silica glass, and each has a refractive index Nd of 1.46. The first lens G1 is a meniscus negative power lens, meaning that one side is convex and the other side is concave. The second lens G2 and the third lens G3 are meniscus positive power lenses, which can converge light, and the concave surface faces the incident direction of the laser, which helps to control the refraction path of the light. The fourth lens G4 is a biconvex positive power lens, which makes its light-convexity ability stronger. The protective lens SG adopts a flat plate structure, which mainly protects the internal lenses from external pollution and damage, while not affecting the normal propagation of light. Therefore, by using the first lens G1, the second lens G2, the third lens G3, and the fourth lens G4 to form a "negative-positive-positive-positive" lens sequence, aberrations can be effectively corrected, allowing light to be uniformly focused over a large area, thus ensuring image quality, achieving the diffraction limit in spot size, and improving processing accuracy. At the same time, in terms of scanning area, a large scanning range of 250mm×250mm can be achieved, reducing the number of times the product needs to be moved during processing and avoiding operations such as repositioning and adjusting processing parameters after each product movement. This makes the processing process more continuous and smooth, significantly improving processing efficiency. It is particularly suitable for applications with high requirements for precision and efficiency, such as copper foil drilling and cutting, and mobile phone screen cutting.

[0034] During operation, the laser beam enters the optical system from the entrance pupil. First, the light passes through the first lens G1, which appropriately diverges the light and adjusts its propagation direction and distribution. Next, the light sequentially enters the second lens G2 and the third lens G3. These two meniscus lenses with positive optical power converge the light and further adjust the focusing degree and angle. Then, the light passes through the fourth lens G4 with a biconvex structure, which further optimizes the focusing effect, converting the light into parallel light that can be accurately focused over a large area. Finally, the light passes through the protective mirror SG with a flat structure. The protective mirror SG prevents external impurities from entering the optical system without changing the light propagation characteristics, ensuring that the internal lenses are not contaminated or damaged, ultimately forming a clear and stable image on the image plane or enabling precise processing operations.

[0035] Reference Figures 1-4 In one embodiment, the large-format ultraviolet telecentric field mirror further includes an entrance pupil plane and an image plane;

[0036] The entrance pupil surface is located on the side of the first lens G1 away from the second lens G2, and the image plane is located on the side of the protective lens SG away from the fourth lens G4. The first interval d0 between the entrance pupil surface and the first lens G1 is 110 mm, the second interval d2 between the first lens G1 and the second lens G2 is 22.5 mm, the third interval d4 between the second lens G2 and the third lens G3 is 14.6 mm, the fourth interval d6 between the third lens G3 and the fourth lens G4 is 68.9 mm, the fifth interval d8 between the fourth lens G4 and the protective lens SG is 6.5 mm, and the sixth interval d10 between the image plane and the protective lens SG is 570 mm.

[0037] In the above embodiments, the large-format ultraviolet telecentric field mirror further includes an entrance pupil surface and an image plane. The entrance pupil surface is located on the side of the first lens G1 away from the second lens G2, so that the entrance pupil surface is positioned at the front end of the first lens G1 along the direction of beam propagation. The image plane is located on the side of the protective mirror SG away from the fourth lens G4, so that the image plane is positioned at the rear end of the protective mirror SG along the direction of beam propagation. That is, the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the protective mirror SG together constitute the core part of the optical system, which is located between the entrance pupil surface and the image plane. The entrance pupil surface and the first lens G1 are located at the rear end of the protective mirror SG along the direction of beam propagation. The first interval d0 between lenses G1 is 110mm, the radius of curvature of the front side of the first lens G1 is -87.56mm, the radius of curvature of the rear side of the first lens G1 is -1134.11mm, and the first center thickness d1 of the first lens G1 is 20.2mm; the second interval d2 between the first lens G1 and the second lens G2 is 22.5mm, the radius of curvature of the front side of the second lens G2 is -393.1mm, the radius of curvature of the rear side of the second lens G2 is -152.9mm, and the second center thickness d3 of the second lens G2 is 39mm. The third interval d4 between the second lens G2 and the third lens G3 is 14.6 mm; the radius of curvature of the front side of the third lens G3 is -1771.1 mm, the radius of curvature of the rear side of the third lens G3 is -223.6 mm, and the third center thickness d5 of the third lens G3 is 45 mm; the fourth interval d6 between the third lens G3 and the fourth lens G4 is 68.9 mm; the radius of curvature of the front side of the fourth lens G4 is 822.4 mm, the radius of curvature of the rear side of the fourth lens G4 is -664.2 mm, and the fourth lens G4... The fourth center thickness d7 is 45mm; the fifth interval d8 between the fourth lens G4 and the protective lens SG is 6.5mm; the fifth center thickness d9 of the protective lens SG is 10mm; and the sixth interval d10 between the image plane and the protective lens SG is 570mm. The above intervals are air gaps. The specific intervals, radii of curvature, and center thicknesses between each lens help to precisely control the refraction and convergence process of light, effectively correct aberrations, improve image quality, and enable the spot size to reach the diffraction limit, thereby achieving clear and accurate imaging and processing in a large format range.

[0038] Furthermore, the total focal length f of the large-format ultraviolet telecentric field lens respectively satisfies the following relationships with the first lens G1, the second lens G2, the third lens G3, and the fourth lens G4: -0.75 < f1 / f < -0.35, 0.9 < f2 / f < 1.4, 1.1 < f3 / f < 1.6, 1.6 < f4 / f < 2.2, where the total focal length of the large-format ultraviolet telecentric field lens is f, and the focal lengths of the first lens G1, the second lens G2, the third lens G3, and the fourth lens G4 are f1, f2, f3, and f4 respectively; among them, from the optical structure parameters of the scanning field lens composed of the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the protective lens SG, f1 / f = -0.48, f2 / f = 1.19, f3 / f = 1.27, f4 / f = 1.9. From the positional relationship of their arrangement, the focal length of the entire large-format ultraviolet telecentric field lens is 420 mm, the wavelength is 355 nm, the telecentricity is 3.4°, the optical scanning angle is ±25°, the diameter of the incident beam is 16 mm, and the scanning range is 250 mm * 250 mm, realizing large-format scanning and high-resolution imaging.

[0039] The surface curvature radius R, thickness T, material refractive index Nd, and Abbe coefficient Vd of each lens provided by the present utility model are shown in the following table:

[0040]

[0041] The above are only the preferred embodiments of the present utility model, and do not limit the patent scope of the present utility model. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present utility model, or directly or indirectly applied in other related technical fields, shall be similarly included in the patent protection scope of the present utility model.

Claims

1. A large-format ultraviolet telecentric field microscope, characterized in that, Starting from the laser incident direction, the structure includes, in sequence, a first lens, a second lens, a third lens, a fourth lens, and a protective mirror; The first lens is a negative power lens with a meniscus structure, the second lens and the third lens are positive power lenses with meniscus structures, the fourth lens is a positive power lens with a biconvex structure, and the protective lens is a flat plate structure. The concave surfaces of the first lens, the second lens and the third lens face the laser incident direction.

2. The large-format ultraviolet telecentric field microscope according to claim 1, characterized in that, The large-format ultraviolet telecentric field mirror also includes an entrance pupil plane and an image plane; The entrance pupil surface is disposed on the side of the first lens away from the second lens, and the image plane is disposed on the side of the protective lens away from the fourth lens. The first interval between the entrance pupil surface and the first lens is 110 mm, the second interval between the first lens and the second lens is 22.5 mm, the third interval between the second lens and the third lens is 14.6 mm, the fourth interval between the third lens and the fourth lens is 68.9 mm, the fifth interval between the fourth lens and the protective lens is 6.5 mm, and the sixth interval between the image plane and the protective lens is 570 mm.

3. The large-format ultraviolet telecentric field microscope according to claim 1, characterized in that, The radii of curvature on the front and rear sides of the first lens are -87.56 mm and -1134.11 mm, respectively, and the thickness of the first center of the first lens is 20.2 mm.

4. The large-format ultraviolet telecentric field microscope according to claim 1, characterized in that, The radii of curvature on the front and rear sides of the second lens are -393.1 mm and -152.9 mm, respectively, and the thickness of the second center of the second lens is 39.5 mm.

5. The large-format ultraviolet telecentric field microscope according to claim 1, characterized in that, The radii of curvature on the front and rear sides of the third lens are -1771.1 mm and -223.6 mm, respectively, and the thickness of the third center of the third lens is 45 mm.

6. The large-format ultraviolet telecentric field microscope according to claim 1, characterized in that, The radii of curvature on the front and rear sides of the fourth lens are 822.4 mm and -664.2 mm, respectively, and the thickness of the fourth lens at its center is 45 mm.

7. The large-format ultraviolet telecentric field microscope according to claim 1, characterized in that, The fifth center thickness of the protective mirror is 10mm.

8. The large-format ultraviolet telecentric field microscope according to any one of claims 1-7, characterized in that, The total focal length of the large-format ultraviolet telecentric lens is f, and the focal lengths of the first lens, the second lens, the third lens, and the fourth lens are f1, f2, f3, and f4, respectively. These focal lengths satisfy the following relationship with the total focal length f of the large-format ultraviolet telecentric lens: -0.75 <f1 / f<-0.35,0.9<f2 / f<1.4,1.1<f3 / f<1.6,1.6<f4 / f<2.2。 9. The large-format ultraviolet telecentric field microscope according to any one of claims 1-7, characterized in that, The first lens, the second lens, the third lens, the fourth lens, and the protective mirror are all made of fused silica glass and have a refractive index Nd of 1.

46.

10. The large-format ultraviolet telecentric field microscope according to claim 1, characterized in that, The entire large-format ultraviolet telecentric field lens has a focal length of 420mm, a wavelength of 355nm, a telecentricity of 3.4°, an optical scanning angle of ±25°, an incident beam diameter of 16mm, and a scanning range of 250mm*250mm.

Images