A large-format scanning round spot lens applicable to fs femtosecond laser

Abstract

The application discloses a large-format scanning round spot lens which can be used under FS femtosecond laser, comprising a first lens, a second lens, a third lens, a fourth lens and a fifth lens which are sequentially arranged along the propagation direction of the light path; the first lens is a positive lens, the second lens is a negative lens, the third lens is a positive lens, the fourth lens is a positive lens, and the fifth lens is a positive lens; the focal length of the large-format scanning round spot lens which can be used under FS femtosecond laser is 350-380 mm. The large-format scanning round spot lens which can be used under FS femtosecond laser solves the problems of the focusing spot of the conventional large-format scanning lens under femtosecond laser, such as spot ellipse, and is suitable for large-format laser cutting, has the characteristics of good spot roundness, small thermal influence area and the like, and can realize precise cutting of an OLED display panel.

Description

TECHNICAL FIELD

[0001] The application relates to a large-format scanning round spot lens applicable to FS femtosecond laser, and belongs to the technical field of laser processing. BACKGROUND

[0002] With laser processing technology playing an increasingly important role in panel processing industry, conventional large-format lenses are widely applied to PS laser and NS laser. The conventional large-format lenses have the characteristics of good processing consistency, high efficiency and long service life, etc. In recent years, with the market's increasing demand for efficiency, FS (femtosecond) laser is favored by the market, and the FS laser has higher cutting efficiency and a smaller heat-affected zone, and is the focus of the next generation of technology development.

[0003] The focusing spot of the conventional scanning lens will be elliptical under the FS laser, which is caused by the group delay dispersion characteristics of the FS laser, so the conventional scanning lens cannot be used on the FS laser. Therefore, the application provides a large-format scanning round spot lens applicable to FS femtosecond laser, which can realize that the laser focusing spot is not elliptical. SUMMARY

[0004] The application provides a large-format scanning round spot lens applicable to FS femtosecond laser, solves the problem that the focusing spot of the conventional large-format scanning lens is elliptical under the femtosecond laser, and is suitable for large-format laser cutting, has the characteristics of good spot roundness and small heat-affected zone, and can realize precise cutting of an OLED display panel.

[0005] To solve the above technical problems, the technical scheme adopted by the application is as follows:

[0006] The large-format scanning round spot lens applicable to FS femtosecond laser comprises first, second, third, fourth and fifth lenses arranged in sequence along the propagation direction of the light path; the first lens is a positive lens, the second lens is a negative lens, the third lens is a positive lens, the fourth lens is a positive lens, and the fifth lens is a positive lens; the focal length of the large-format scanning round spot lens applicable to FS femtosecond laser is 350-380 mm.

[0007] As one of the preferred implementation schemes of the application, the focal length of the first lens is f1=1502 mm; the focal length of the second lens is f2=--194 mm; the focal length of the third lens is f3=800 mm; the focal length of the fourth lens is f4=449 mm; and the focal length of the fifth lens is f2=712 mm.

[0008] The large-format scanning round spot lens applicable to FS femtosecond laser is applied to ultraviolet laser with FS of less than 500.

[0009] The lens material of each lens is high-quality fused quartz and single crystal CaF2.

[0010] To improve the focusing effect, the material of the first lens, the fourth lens and the fifth lens is high-quality fused quartz, and the material of the second lens and the third lens is single crystal CaF2.

[0011] In the direction of light path propagation, the two surfaces of the first lens are a first object side surface and a first image side surface in sequence, the two surfaces of the second lens are a second object side surface and a second image side surface in sequence, the two surfaces of the third lens are a third object side surface and a third image side surface in sequence, the two surfaces of the fourth lens are a fourth object side surface and a fourth image side surface in sequence, and the two surfaces of the fifth lens are a fifth object side surface and a fifth image side surface in sequence; to further ensure the focusing effect, the curvature radius of the first object side surface is-110.30±0.01mm, the curvature radius of the first image side surface is-98.50±0.01mm; the curvature radius of the second object side surface is-80.98±0.01mm, the curvature radius of the second image side surface is-1332.6±0.01mm; the curvature radius of the third object side surface is-281±0.01mm, the curvature radius of the third image side surface is-163.45±0.01mm; the curvature radius of the fourth object side surface is-1500.00±0.01mm, the curvature radius of the fourth image side surface is-188.8±0.01mm; the curvature radius of the fifth object side surface is 486.00±0.01mm, and the curvature radius of the fifth image side surface is-1100.00±0.01mm.

[0012] To better ensure the focusing quality, the central thickness of the first lens is 10.5±0.1mm, the central thickness of the second lens is 28.5±0.1mm, the central thickness of the third lens is 36.2±0.1mm, the central thickness of the fourth lens is 38.7±0.1mm, and the central thickness of the fifth lens is 32.3±0.1mm.

[0013] As one of the specific implementation schemes, the aperture of the first lens is 72.0±0.1mm, the aperture of the second lens is 142.0±0.1mm, the aperture of the third lens is 195.0±0.1mm, the aperture of the fourth lens is 227.0±0.1mm, and the aperture of the fifth lens is 251.0±0.1mm.

[0014] The technologies not mentioned in the present application refer to the prior art.

[0015] The present application can be used for large-format scanning round spot lenses under FS femtosecond lasers, solves the problems of focusing spot ellipse under femtosecond lasers in conventional large-format scanning lenses, is suitable for large-format laser cutting, has the characteristics of good spot roundness, small thermal influence area and the like, and can realize precise cutting of OLED display panels. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 This is an optical structure diagram of the large-format scanning circular spot lens that can be used under FS femtosecond laser according to the present invention;

[0017] Figure 2 This is an actual dot pattern of the focused spot under femtosecond laser light from a conventional lens (343nm, F367 lens).

[0018] Figure 3 This is an actual dot pattern of the focused spot of the large-format scanning circular spot lens that can be used in FS femtosecond lasers according to the present invention;

[0019] Figure 4 This is a dot plot of the large-format scanning circular spot lens that can be used in FS femtosecond lasers according to the present invention;

[0020] Figure 5 This is a field curvature diagram of a large-format scanning circular spot lens that can be used under FS femtosecond laser according to the present invention;

[0021] Figure 6 The MTF curve of this invention is used for a large-format scanning circular spot lens under FS femtosecond laser. Detailed Implementation

[0022] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments.

[0023] Example 1

[0024] like Figure 1 As shown: A large-format scanning circular spot lens for use with FS femtosecond lasers includes a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, and a window lens 6 arranged sequentially along the optical path propagation direction; the first lens is a positive lens, the second lens is a negative lens, the third lens is a positive lens, the fourth lens is a positive lens, and the fifth lens is a positive lens; the focal length of the first lens is f1 = 1502 mm; the focal length of the second lens is f2 = -194 mm; the focal length of the third lens is f3 = 800 mm; the focal length of the fourth lens is f4 = 449 mm; and the focal length of the fifth lens is f5 = 712 mm.

[0025] In the direction of the light path, the two surfaces of the first lens are a first object side surface and a first image side surface in sequence, the two surfaces of the second lens are a second object side surface and a second image side surface in sequence, the two surfaces of the third lens are a third object side surface and a third image side surface in sequence, the two surfaces of the fourth lens are a fourth object side surface and a fourth image side surface in sequence, and the two surfaces of the fifth lens are a fifth object side surface and a fifth image side surface in sequence; the curvature radius of the first object side surface is -110.30 mm, and the curvature radius of the first image side surface is -58.40 mm; the curvature radius of the second object side surface is -61.11 mm, and the curvature radius of the second image side surface is 1023.00 mm; the curvature radius of the third object side surface is -442.48 mm, and the curvature radius of the third image side surface is -124.64 mm; the curvature radius of the fourth object side surface is -1800.00 mm, and the curvature radius of the fourth image side surface is -342.00 mm; and the curvature radius of the fifth object side surface is 327.00 mm, and the curvature radius of the fifth image side surface is -1400.00 mm.

[0026] The materials of the first lens, the fourth lens and the fifth lens are fused quartz of Corning 7980, and the materials of the second lens and the third lens are single crystal CaF2.

[0027] The working parameters of the large-format scanning round spot lens used in FS femtosecond laser are as follows:

[0028] The laser wavelength is 343 nm.

[0029] The working format is 200x200 mm.

[0030] The focal length is 367 mm.

[0031] The specific parameters of the lenses in the example

[0032]

[0033]

[0034] The laser adopts a 343 nm 500 FS laser, and the incident spot diameter of the laser is 12 mm. Figure 2 The spot effect diagram of the existing 343 nm, F367 lens under FS is shown in the figure, and the focused spot is deformed into an oval shape, Figure 3 The spot effect diagram of the lens (343 nm) of the application under FS is shown in the figure, and the focused spot is circular without deformation problem, and it can be seen that the application has obvious inhibition effect on the spot deformation problem under FS. Figure 4 The spot diagram of the lens of the application is shown in the figure, Figure 4 It can be seen that the design is a diffraction limit design. Figure 5 The field curvature diagram of the lens of the application is shown in the figure, Figure 5 It can be seen that the field curvature is less than 0.2 mm, and the flat field property is good.Figure 6 For the MTF curve of the above lens of the present application, from Figure 6 It can be seen that the design value is close to the theoretical value.

Claims

1. A large-format scanning round spot lens for use under FS femtosecond laser, characterized in that: The first lens, the second lens, the third lens, the fourth lens and the fifth lens are arranged in sequence along the light path direction; the first lens is a positive lens, the second lens is a negative lens, the third lens is a positive lens, the fourth lens is a positive lens, and the fifth lens is a positive lens; the focal length of the large-format scanning round spot lens for FS femtosecond laser is 350-380 mm; The focal length of the first lens is f1=1502 mm; the focal length of the second lens is f2=-194 mm; the focal length of the third lens is f3=800 mm; the focal length of the fourth lens is f4=449 mm; and the focal length of the fifth lens is f5=712 mm. The center distance between the first lens and the second lens is 56.5±0.1 mm, the center distance between the second lens and the third lens is 32.0±0.1 mm, the center distance between the third lens and the fourth lens is 0.5±0.1 mm, the center distance between the fourth lens and the fifth lens is 0.5±0.1 mm, and the center distance between the fifth lens and the protective window is 6.4±0.1 mm.

2. The large-format scanning spot lens for use under FS femtosecond laser according to claim 1, wherein: It is applied to ultraviolet laser with <500 FS.

3. The large-format scanning spot lens for use under FS femtosecond laser according to claim 1 or 2, characterized in that: The lens materials selected for each lens are fused quartz and single crystal CaF2.

4. The large-format scanning spot lens for use under FS femtosecond laser according to claim 3, characterized in that: The materials used for the first lens, the fourth lens and the fifth lens are high-quality fused quartz, and the materials used for the second lens and the third lens are single crystal CaF2.

5. The large-format scanning round spot lens for FS femtosecond laser according to claim 1 or 2, characterized in that: In the light path direction, the two surfaces of the first lens are a first object side surface and a first image side surface in sequence, the two surfaces of the second lens are a second object side surface and a second image side surface in sequence, the two surfaces of the third lens are a third object side surface and a third image side surface in sequence, the two surfaces of the fourth lens are a fourth object side surface and a fourth image side surface in sequence, and the two surfaces of the fifth lens are a fifth object side surface and a fifth image side surface in sequence; the curvature radius of the first object side surface is -110.30±0.01 mm, the curvature radius of the first image side surface is -98.50±0.01 mm; the curvature radius of the second object side surface is -80.98±0.01 mm, the curvature radius of the second image side surface is -1332.6±0.01 mm; the curvature radius of the third object side surface is -281±0.01 mm, the curvature radius of the third image side surface is -163.45±0.01 mm; the curvature radius of the fourth object side surface is -1500.00±0.01 mm, the curvature radius of the fourth image side surface is -188.8±0.01 mm; and the curvature radius of the fifth object side surface is 486.00±0.01 mm, the curvature radius of the fifth image side surface is -1100.00±0.01 mm.

6. The large-format scanning round spot lens for FS femtosecond laser according to claim 1 or 2, characterized in that: The center thickness of the first lens is 10.5±0.1 mm, the center thickness of the second lens is 28.5±0.1 mm, the center thickness of the third lens is 36.2±0.1 mm, the center thickness of the fourth lens is 38.7±0.1 mm, and the center thickness of the fifth lens is 32.3±0.1 mm.

7. The large-format scanning spot lens for use under FS femtosecond laser according to claim 1 or 2, characterized in that: The aperture of the first lens is 72±0.1 mm, the aperture of the second lens is 142±0.1 mm, the aperture of the third lens is 195±0.1 mm, the aperture of the fourth lens is 227±0.1 mm, and the aperture of the fifth lens is 251±0.1 mm.

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