High-power laser continuous zooming output head optical system

Abstract

The embodiment of the utility model provides a high-power laser continuous zoom output head optical system, which comprises a collimating lens group, a first fixed lens group, a zoom lens and a second fixed lens group which are sequentially and coaxially arranged along a laser transmission direction, the first fixed lens group is used for focusing the laser beams, the zoom lens is used for zooming and expanding the laser, and the second fixed lens group is used for focusing the laser beams again.

Description

Technical Field

[0001] This document relates to the field of laser processing technology, and in particular to an optical system of a high-power laser continuous zoom output head. Background Art

[0002] In the field of laser processing, in order to meet the needs of the corresponding processing technology, the emitted laser must first be collimated, focused, and shaped. In laser processing, in order to process workpieces of different sizes, the size of the output light spot must be adjustable and the uniformity must be good to meet the processing requirements. At present, most laser processing laser output heads can only achieve collimation and beam expansion of fixed-size spots, and cannot adjust the spot size or the adjustable range of the spot size is very small. A laser beam expansion system that can achieve continuous magnification is urgently needed to meet the needs of laser processing.

[0003] In high-power laser processing systems, the number of optical system lenses should be as small as possible to reduce power loss and heat accumulation in laser transmission and prevent structural damage caused by excessive temperature. Currently, most variable-magnification beam expanders are not suitable for use in high-power laser processing systems. A continuous variable-magnification beam expander system that can withstand high-power lasers is urgently needed to meet the needs of high-power laser processing.

[0004] In summary, there are problems in the prior art in that the zoom range, spot uniformity, and maximum tolerable power density of the current laser zoom beam expansion system cannot simultaneously meet the requirements of laser processing. Utility Model Content

[0005] The utility model aims to provide a high-power laser continuously variable magnification output head optical system, aiming to solve the above-mentioned problems in the prior art.

[0006] The utility model provides a high-power laser continuous zoom output head optical system, comprising:

[0007] A collimating lens group, a first fixed lens group, a magnification lens and a second fixed lens group are coaxially arranged in sequence along the laser transmission direction, wherein the collimating lens group is used to collimate and compensate the laser, the first fixed lens group is used to focus the laser beam, the magnification lens is used to expand the laser beam, and the second fixed lens group is used to focus the laser beam again.

[0008] By adopting the embodiment of the utility model, the incident laser output by optical fiber coupling can be collimated and expanded, the zoom range is large, good light spot uniformity can be maintained, and high-power laser can be withstood. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate one or more embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0010] Figure 1 It is a cross-sectional schematic diagram of Example 1 of the utility model at a magnification of 0.5 times;

[0011] Figure 2 It is a cross-sectional schematic diagram of Example 1 of the utility model at a magnification of 1 times;

[0012] Figure 3 It is a cross-sectional schematic diagram of Example 1 of the utility model at a 2-fold magnification;

[0013] Figure 4 It is a cross-sectional schematic diagram of Example 1 of the utility model at a magnification of 4 times;

[0014] Figure 5a This is the light spot diagram corresponding to 0.5 times magnification of Example 1 of the utility model;

[0015] Figure 5b This is the light spot energy distribution diagram corresponding to 0.5 times magnification of Example 1 of the utility model;

[0016] Figure 6a This is the light spot diagram corresponding to 1x magnification in Example 1 of the utility model;

[0017] Figure 6b This is the light spot energy distribution diagram corresponding to 1x magnification in Example 1 of the utility model;

[0018] Figure 7a This is the light spot diagram corresponding to 2 times magnification of Example 1 of the utility model;

[0019] Figure 7b This is the light spot energy distribution diagram corresponding to 2 times magnification in Example 1 of the utility model.

[0020] Figure 8a This is the light spot diagram corresponding to 4 times magnification of Example 1 of the utility model.

[0021] Figure 8b This is the light spot energy distribution diagram corresponding to 4 times magnification of Example 1 of the utility model;

[0022] Fig. 9 This is a schematic diagram of the optical system of a high-power laser continuous zoom output head according to an embodiment of the utility model. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the technical solutions in one or more embodiments of this specification, the technical solutions in one or more embodiments of this specification will be clearly and completely described below in conjunction with the drawings in one or more embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of them. Based on one or more embodiments of this specification, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this document.

[0024] According to an embodiment of the utility model, a high-power laser continuous zoom output head optical system is provided, such as Fig. 9 As shown, the optical system of the high-power laser continuous zoom output head according to the embodiment of the utility model specifically includes:

[0025] A collimating lens group 90, a first fixed lens group 91, a magnification lens 92 and a second fixed lens group 93 are coaxially arranged in sequence along the laser transmission direction, wherein the collimating lens group 90 is used to collimate and compensate the laser, the first fixed lens group 91 is used to focus the laser beam, the magnification lens 92 is used to expand the laser beam, and the second fixed lens group 93 is used to focus the laser beam again.

[0026] Specifically, the collimating lens group 90 specifically includes: a first lens and a second lens arranged in sequence along the laser transmission direction, wherein the optical power of the first lens and the second lens are both positive. The first lens and the second lens are plano-convex positive lenses.

[0027] The first fixed lens group 91 specifically includes: a third lens and a fourth lens arranged in sequence along the laser transmission direction, wherein the optical power of the third lens and the fourth lens are positive and negative in sequence, the third lens is a plano-convex positive lens, and the fourth lens is a plano-concave negative lens.

[0028] The variable power lens 92 specifically includes: a fifth lens arranged in sequence along the laser transmission direction, wherein the optical power of the fifth lens is negative and the fifth lens is a double concave negative lens.

[0029] The second fixed lens group 93 specifically includes: sixth lenses arranged in sequence along the laser transmission direction, wherein the optical power of the sixth lenses is positive and the sixth lenses are plano-convex positive lenses.

[0030] In an embodiment of the present invention, the lenses of the collimating lens group, the first fixed lens group, the variable power lens and the second fixed lens group are made of fused quartz.

[0031] The above technical solution of the embodiment of the utility model is described in detail below in conjunction with the accompanying drawings.

[0032] According to the high-power laser continuous zoom output head optical system of the utility model, its different zoom structures are as follows Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown. The incident direction of the laser passes from left to right, sequentially through the first lens G1 with a focal length of f1, the second lens G2 with a focal length of f2, the third lens G3 with a focal length of f3, the fourth lens G4 with a focal length of f4, the fifth lens G5 with a focal length of f5, and the sixth lens G6 with a focal length of f6.

[0033] The first lens G1 and the second lens G2 form an adjustable collimating lens group, and the focal length of the collimating lens group is f 准 =35mm, the third lens G3 and the fourth lens G4 form a front fixed lens group, the focal length of the front fixed lens group is f 固1 =285mm, the fifth lens G5 forms a zoom lens group, and the focal length of the zoom lens group is f 变 =-45mm, the sixth lens G6 constitutes a rear fixed lens group, and the focal length of the rear fixed lens group is f 固2 =145mm.

[0034] The first lens G1 is a plano-convex positive lens, the second lens G2 is a plano-convex positive lens, and the lenses of the collimating group satisfy the combined focal length f 准 =35mm.

[0035] The third lens G3 is a plano-convex positive lens, the fourth lens G4 is a plano-concave negative lens, and the lenses of the front fixed group satisfy the combined focal length f 固1 =285mm.

[0036] The fifth lens G5 is a double concave negative lens, and the focal length of the zoom lens group meets f 变 =-45mm.

[0037] The sixth lens G6 is a plano-convex positive lens, and the focal length of the rear fixed lens group satisfies f 固2 =145mm.

[0038] Example 1

[0039] The distance D4 between the front fixed group and the variable magnification group and the distance D1 between the adjustable collimator and the fixed collimator at different magnifications are shown in Table 1. Table 2 shows the lens structure parameters of Example 1.

[0040] Table 1

[0041] Table 2

[0042]

[0043]

[0044] like Figure 1-4 As shown, the optical structure diagram of the optical system when the magnification is 0.5 times, 1 times, 2 times, and 4 times respectively. Along the optical path direction, from left to right are:

[0045] The left and right sides of the first lens G1 are respectively a first left lens surface and a first right lens surface;

[0046] The left and right sides of the second lens G2 are respectively a second left lens surface and a second right lens surface;

[0047] The left and right sides of the third lens G3 are respectively a third left lens surface and a third right lens surface;

[0048] The left and right sides of the fourth lens G4 are respectively a fourth left lens surface and a fourth right lens surface;

[0049] The left and right sides of the fifth lens G5 are respectively a fifth left lens surface and a fifth right lens surface;

[0050] Figure 5a , Figure 5b is the spot diagram and spot energy distribution of the optical system when the magnification is 0.5 times, Figure 6a , Figure 6b It is the spot diagram and spot energy distribution diagram when the optical system is magnified by 1 times. Figure 7a , Figure 7b The spot diagram and spot energy distribution of the optical system when the magnification is 2 times, Figure 8a , Figure 8b The light spot diagram and light spot energy distribution diagram are shown when the optical system has a magnification of 4. It can be seen that within all magnification ranges, the light spot diagrams are all squares with clear boundaries, and the uniformity of the light spot energy distribution is greater than 80%, which indicates that the embodiment of the utility model has very good imaging quality within the entire magnification range and can ensure that the light spot uniformity is not affected.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.

Claims

1. A high-power laser continuous zoom output head optical system, characterized in that: include: A collimating lens group, a first fixed lens group, a magnification lens and a second fixed lens group are coaxially arranged in sequence along the laser transmission direction, wherein the collimating lens group is used to collimate and compensate the laser, the first fixed lens group is used to focus the laser beam, the magnification lens is used to expand the laser beam, and the second fixed lens group is used to focus the laser beam again.

2. The optical system according to claim 1, characterized in that The collimating lens group specifically comprises: A first lens and a second lens are sequentially arranged along a laser transmission direction, wherein the optical focal powers of the first lens and the second lens are both positive.

3. The optical system according to claim 2, characterized in that The first lens and the second lens are plano-convex positive lenses.

4. The optical system according to claim 1, characterized in that The first fixed lens group specifically includes: A third lens and a fourth lens are sequentially arranged along the laser transmission direction, wherein the optical power of the third lens and the fourth lens is positive and negative respectively.

5. The optical system according to claim 4, characterized in that The third lens is a plano-convex positive lens, and the fourth lens is a plano-concave negative lens.

6. The optical system according to claim 1, characterized in that The variable magnification lens specifically comprises: A fifth lens is sequentially arranged along the laser transmission direction, wherein the optical power of the fifth lens is negative.

7. The optical system according to claim 6, characterized in that The fifth lens is a biconcave negative lens.

8. The optical system according to claim 1, characterized in that The second fixed lens group specifically includes: A sixth lens is sequentially arranged along the laser transmission direction, wherein the optical power of the sixth lens is positive.

9. The optical system according to claim 8, characterized in that The sixth lens is a plano-convex positive lens.

10. The optical system according to claim 1, characterized in that The lenses of the collimating lens group, the first fixed lens group, the variable power lens and the second fixed lens group are made of fused quartz.

Images