Reverse beam combining weaving and light beam homogenizing method for optical fiber bundles

Abstract

The invention relates to a method for reversely combining, weaving and homogenizing optical fiber bundles, which comprises the following steps of: reversely combining branch optical fiber bundles, coating each branch optical fiber with different colors, dividing a branch end into regions, extracting a bundle of optical fibers from the corresponding region of each branch, and grouping, wherein each group is formed by bundling a small strand of optical fibers to form a light-passing micro-region. The micro-regions are randomly and uniformly distributed and arranged on a light incident end face (a beam combining end) to form a required end face shape. Reverse beam combination is adopted, and it is guaranteed that the number of branch optical fibers of the branch optical fiber bundles is uniform; the light-passing micro-area formed by grouping or weaving the optical fibers can refine and homogenize the light emitted by the light source and is also called micro-area homogenization, and then the small optical fibers are bundled and integrated into the whole optical fiber bundle, so that the light emitted by the light source is homogenized again, and uniform bundling is realized.

Description

Technical Field

[0001] The invention relates to the technical field of optical fiber bundles, in particular to a method for reverse bundle combining and braiding of optical fiber bundles and light beam homogenization. Background Art

[0002] Fiber optic bundles, as components composed of a large number of optical fiber strands, have shown extensive application potential and excellent development prospects in many high-tech fields such as energy transmission and image transmission, such as laser medical treatment, energy detection, ultraviolet lithography and quality inspection. However, the manufacturing process of branched optical fiber bundles on the current market has significant defects, which restricts its performance optimization and cost reduction.

[0003] The traditional manufacturing process is a beam splitting step, which is different from beam combining. It is customary to complete the input end of the optical fiber bundle first, and then process the branch end. This sequential operation not only increases the complexity of the process, but also makes it difficult to accurately control the number of optical fiber filaments in each branch during the branch end production process, which in turn causes the problem of uneven light output energy. In addition, since optical fiber bundles are often used to transmit non-homogeneous light sources, improving the uniformity of the light field distribution after transmission becomes a major challenge.

[0004] In order to address the problem of insufficient uniformity of the light source itself, existing technologies tend to use a method of randomly and disorderly arranging optical fibers when making branches, in order to achieve a homogenized light beam. However, the effect of this method is often unsatisfactory: either the fiber mixing is insufficient to meet the requirements of light field uniformity; or excessive scattering causes the optical fibers to be easily damaged, resulting in a significant increase in the breakage rate and low production efficiency. This trade-off not only increases uncertainty in the production process, but also causes a significant decline in yield on the product production line, directly pushing up production costs.

[0005] In summary, the current manufacturing process of branched light guide fiber bundles has obvious shortcomings in maintaining the consistency of the number of optical fibers, improving the uniformity of the light field, and controlling the production cost. Therefore, an innovative manufacturing process is urgently needed to overcome the limitations of the existing technology, achieve efficient homogenization of the light beams between and within the branches, and at the same time reduce production costs and improve product yield. Summary of the invention

[0006] In order to overcome the shortcomings of the above-mentioned prior art, the present invention provides a method for reverse beam combining and braiding of optical fiber bundles and beam homogenization, aiming to optimize the beam energy distribution and light field uniformity of single-branch or multi-branch optical fiber bundles. This method solves the problem of beam energy difference caused by poor fiber filament dispersion and mixing effect and uneven number of branch optical fiber filaments in traditional optical fiber bundle manufacturing through reverse beam combining technology, micro-area structure and uniform arrangement of micro-areas on the incident end face, and significantly improves the uniformity of light field distribution on the light output end face.

[0007] The technical solution of the present invention is as follows:

[0008] A method for reverse beam combining and braiding of optical fiber bundles and light beam homogenization, characterized in that the method comprises the following steps:

[0009] Provided is an optical fiber comprising a core and a cladding, wherein the refractive index of the cladding material is lower than the refractive index of the core material;

[0010] According to the total amount of optical fiber filaments and the number of branches required for the optical fiber bundle, the optical fiber is cut into equal parts in the number of branches for standby use, and then braided and reversely bundled, wherein the optical fiber coatings constituting each branch are distinguished by different colors;

[0011] At each branch end, n micro-region production areas of equal area are divided, and a bundle of optical fibers is extracted from the corresponding area of ​​each branch for grouping. Each group is formed by a small strand of optical fiber filaments, forming a light-transmitting micro-region; wherein the size of the micro-region is affected by the diameter of the optical fiber and the number of branches N, and within the micro-region, the number of optical fibers from the N branches is consistent; for multi-type branch optical fiber bundles, if the number of input ends is M, then N divided by M is an integer to ensure that the micro-region bundle is evenly divided into M large bundles;

[0012] At the light incident end face, i.e., the beam combining end, the multiple light-transmitting micro-regions are randomly and evenly arranged and bundled into the entire end face to form the desired end face shape;

[0013] The reverse beam combining includes first completing the production of the branch ends of a single-branch optical fiber bundle and then performing the beam combining operation, and first completing the production of the branch ends with more branches of a multi-branch optical fiber bundle and then performing the beam combining operation.

[0014] Furthermore, in step 3), the size of the micro-region is also affected by the following factors:

[0015] a) The smaller the diameter of the optical fiber, the smaller the micro-region that can be achieved;

[0016] b) The larger the number of branches N, the larger the size of the micro-domain.

[0017] Furthermore, in step 4), the multiple light-transmitting micro-area head ends are aligned and placed in a mold that matches the light-transmitting area of ​​the optical fiber bundle, or are manually hooped into the desired end face shape without a mold, and randomly and evenly arranged and bundled into the entire end face to form the desired optical fiber bundle end face shape.

[0018] Furthermore, the mold material is a polymer material or a metal material.

[0019] Furthermore, the end face of the optical fiber bundle is in a circular, wavy, rectangular or polygonal shape.

[0020] Furthermore, between step 3) and step 4), a light field homogenization process is performed on the light-transmitting micro-region to improve the light field uniformity in each micro-region.

[0021] Furthermore, the light field homogenization process includes adjusting the arrangement of optical fiber filaments, the diameter of optical fiber filaments or the spacing parameters between optical fiber filaments to achieve light field homogenization in the micro area.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1) The production process of traditional multi-branch optical fiber bundles often starts from the light incident end, first the optical fiber arrangement at the incident end is finalized, and then the optical fiber is picked out from the middle section of the optical fiber to perform the beam splitting step. In this way, it is difficult to ensure that the number of optical fibers in each branch is uniform. The present invention adopts the reverse beam combining technology, that is, the production of each branch is completed first, and then the beam combining operation is performed. This reverse beam combining method not only improves the flexibility of optical fiber bundle production, but also facilitates accurate regional division and optical fiber grouping at the branch end, providing favorable conditions for subsequent light field homogenization processing.

[0024] 2) The present invention divides the branch end into several regions of equal area, and extracts a bundle of optical fibers from the corresponding regions of each branch for grouping to form a plurality of light-transmitting micro-regions. Each light-transmitting micro-region is formed by a small bundle of optical fiber filaments, which not only improves the light extraction efficiency of the optical fiber bundle, but also enables the light field to be initially homogenized within the micro-region. By adjusting parameters such as the arrangement mode, diameter or spacing of the optical fiber filaments, the light field distribution within the micro-region can be further optimized and the uniformity of the light field can be improved. At the same time, on the light incident end face, a plurality of light-transmitting micro-regions are randomly and evenly arranged to form the desired end face shape of the optical fiber bundle. This random and evenly distributed arrangement not only breaks the regularity of the traditional optical fiber bundle arrangement, but also effectively avoids the problem of insufficient illumination uniformity caused by improper arrangement of optical fiber filaments. Through random and evenly distributed arrangement, the light field can be more evenly distributed on the light-emitting end face of the optical fiber bundle, thereby improving the light field uniformity of the entire light-emitting end face. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 This is a schematic diagram of the end face of the constructed hexagonal light-transmitting micro-region.

[0027] Figure 2 Schematic diagram of the braiding operation framework of the one-to-three optical fiber bundle in the embodiment

[0028] Figure 3 Schematic diagram of the division of the branch end micro-area production area

[0029] Figure 4 Schematic diagram of the reverse bundling and braiding process of the one-to-three optical fiber bundle in the embodiment

[0030] Figure 5 This is a schematic diagram of the bundle end after weaving

[0031] Throughout the drawings, reference numerals are used to designate various elements and structures, wherein:

[0032] 1- Black, white and gray represent the optical fibers from the three branches.

[0033] 2-3 branches of a 1-to-3 fiber bundle

[0034] 3-Branch fixing fixture

[0035] 4-Inner diameter shrink ring

[0036] 5-One-to-three fiber bundle combined end

[0037] 6-Fiber optic wire

[0038] 7-Light-transmitting micro-region composed of optical fiber filaments from 3 branches

[0039] 8- The framed area represents the end surface of the homogenized micro-region DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0041] A method for reverse beam combining and braiding of optical fiber bundles and light beam homogenization comprises the following steps:

[0042] 1) Provide an optical fiber, including a core and a cladding, wherein the core of the optical fiber is made of glass or other materials, and the cladding is made of glass or other materials with a refractive index lower than that of the core material

[0043] 2) According to the total amount of optical fiber and the number of branches required for the optical fiber bundle, the optical fiber is cut into equal parts for the number of branches for later use, and then braided and reversed into bundles. The optical fiber coatings that make up each branch can be distinguished by different colors, which is convenient for taking optical fibers from each branch to construct micro-areas.

[0044] 3) The size of the micro-zone is affected by factors such as the diameter of the optical fiber and the number of branches N.

[0045] The smaller the diameter of the optical fiber, the smaller the micro-region that can be achieved;

[0046] The larger the number of branches N is, the larger the size of the micro-region is;

[0047] In a micro-area, the number of optical fibers from the N branches must be basically the same;

[0048] When multi-dividing into multiple, if the number of input ports is M, then N divided by M must be an integer to ensure that the micro-area beam is evenly divided into M large beams.

[0049] The light-transmitting micro-area is constructed starting from about 400 mm away from the beam-combining end face, and can also be started closer or farther depending on actual needs.

[0050] 4) Micro-zone construction method: n micro-zone production areas of equal area are divided at each branch end, and each area is numbered 1, 2, 3, ... n. Multiple micro-zones can be made in each micro-zone production area. The above-mentioned light-transmitting micro-zone can be fixed by bundling multiple optical fibers, and the optical fibers in a single micro-zone must come from the micro-zone production area with the same number. The optical fiber end face of the micro-zone can be constructed into circular, wavy, rectangular, polygonal and other shapes as needed. Generally speaking, for a circular beam combining end, the micro-zone end face can be constructed into a hexagonal shape; for a rectangular beam combining end, the micro-zone end face can be constructed into a rectangular shape. If the goal of high transmittance of the optical fiber bundle is to achieve, the end face optical fiber needs to be tightly packed with hexagons, and the micro-zone should be a hexagonal sub-bundle.

[0051] 5) Align the light-transmitting micro-region heads with the above-mentioned size and shape and place them in a mold that matches the light-transmitting region of the optical fiber bundle, distribute them randomly and evenly, and bundle them into the entire end face.

[0052] The reverse beam combining is to complete the production of the branch ends first and then perform the beam combining operation for the single-to-multiple branch optical fiber bundle.

[0053] The reverse beam combining is characterized in that for a multi-branch optical fiber bundle, the branch ends with more branches are first made, and then the beam combining operation is performed.

[0054] The weaving operation includes the construction of the light-transmitting micro-regions and the uniform arrangement of the micro-regions on the end surface after the micro-regions are constructed.

[0055] The mold material can be a polymer material or a metal material; or the mold can be omitted and the end face can be manually shaped into the desired shape.

[0056] The size and shape of each light-transmitting micro-area constituting the branch optical fiber bundle end face need not be specially specified to be consistent

[0057] There is no clear sequence of weaving and reverse bundling operations involved

[0058] Embodiment: A method for reversely combining and braiding a one-to-three optical fiber bundle and homogenizing the optical beam, wherein the optical input end and the optical output end of the optical fiber bundle are both circular. The method comprises the following steps:

[0059] Take a total of 10km long optical fiber, the core material is pure quartz, the cladding material is fluorine-doped quartz, and the outer diameter of the bare fiber is 190μm

[0060] The optical fibers are cut into fixed lengths of 1500±100mm, a total of about 6666 fibers can be cut and divided into three parts by counting. One end of the three parts of optical fiber constitutes the three branches of the one-to-three optical fiber bundle, and the other end will be tied and fixed after braiding.

[0061] Place the three branch fiber bundles vertically as follows: Figure 2 The braiding operation frame shown is fixed at one end with a branch fixing clamp

[0062] After one end is fixed, pass the other end of the 3 branch fiber bundles through Figure 2 The inner diameter shrinking ring shown in the figure can freely adjust the diameter of the inner ring and can move in the vertical direction

[0063] Will Figure 2 The inner diameter of the middle shrink ring is adjusted to about 30mm, so that the optical fiber passing through it gradually converges into a circle, and the height of the shrink ring is adjusted to about 400mm from the bottom of the optical fiber.

[0064] At the branch end, 20 micro-area production areas of equal area are divided, and each area is numbered 1, 2, 3, ... 20. Multiple micro-areas can be produced in each micro-area production area, as shown in the schematic diagram Figure 3 shown.

[0065] like Figure 4 As shown in the figure, an equal amount of optical fibers are taken from the three branched optical fibers to construct a hexagonal light-transmitting micro-region. Figure 1 As shown. The number of optical fibers in this light-transmitting micro-area accounts for about 0.3% of the total number of optical fibers.

[0066] The location of the construction micro-zone starts from 400mm away from the beam combining end to avoid problems such as fiber breakage caused by too small a construction micro-zone area and increased fiber loss caused by too small a fiber bending radius.

[0067] The constructed light-transmitting micro-region heads are aligned and placed in the mold, and randomly and evenly distributed on the entire end surface to form a light-transmitting end surface, such as Figure 5 shown.

[0068] The experiment shows that the present invention adopts the scheme of reverse beam combining, which avoids the influence of different numbers of optical fiber filaments in each branch on the uniformity between branches. The micro-area production area is constructed in each branch of the optical fiber bundle and the optical fiber filaments are extracted from it to construct a fine light-transmitting micro-area, so as to achieve micro-area homogenization; and then the micro-areas are combined to achieve uniform beam collection. This method is simple, convenient and easy to implement. Compared with the traditional scheme, it further optimizes the uniformity of the light field distribution between each branch of the optical fiber bundle and within the branch.

[0069] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the appended claims of the present invention.

Claims

1. A method for reverse beam combining and beam homogenization of optical fiber bundles, characterized in that: The method comprises the following steps: 1) Provide an optical fiber, the optical fiber comprising a core and a cladding, wherein the refractive index of the cladding material is lower than the refractive index of the core material; 2) According to the total amount of optical fiber filaments and the number of branches required for the optical fiber bundle, the optical fiber is cut into equal parts in the number of branches for standby use, and then braided and reversely bundled, wherein the coating of the optical fiber constituting each branch is distinguished by different colors; 3) Divide each branch end into n equal-area micro-region production areas, and extract a bundle of optical fibers from the corresponding area of ​​each branch for grouping, each group is formed by a small strand of optical fiber filaments, forming a light-transmitting micro-region; wherein the size of the micro-region is affected by the diameter of the optical fiber and the number of branches N, and within the micro-region, the number of optical fibers from the N branches is consistent; for multi-type branch optical fiber bundles, if the number of input ends is M, then N divided by M is an integer to ensure that the micro-region bundle is evenly divided into M large bundles; 4) At the light incident end face, i.e., the beam combining end, the multiple light-transmitting micro-regions are randomly and evenly arranged and bundled into the entire end face to form the desired end face shape; The reverse beam combining includes first completing the production of the branch ends of a single-branch optical fiber bundle and then performing the beam combining operation, and first completing the production of the branch ends with more branches of a multi-branch optical fiber bundle and then performing the beam combining operation.

2. The method for reverse beam combining and beam homogenization of optical fiber bundles according to claim 1, characterized in that: In step 3), the size of the micro-region is also affected by the following factors: a) The smaller the diameter of the optical fiber, the smaller the micro-region that can be achieved; b) The larger the number of branches N, the larger the size of the micro-domain.

3. The method for reverse beam combining and beam homogenization of optical fiber bundles according to claim 1, characterized in that: In step 4), the multiple light-transmitting micro-area head ends are aligned and placed in a mold that matches the light-transmitting area of ​​the optical fiber bundle, or are manually hooped into the desired end face shape without a mold, and randomly and evenly arranged and bundled into the entire end face to form the desired optical fiber bundle end face shape.

4. The method for reverse beam combining and beam homogenization of optical fiber bundles according to claim 3, characterized in that: The mold material is a polymer material or a metal material.

5. The method for reverse beam combining and beam homogenization of optical fiber bundles according to claim 3, characterized in that: The end face shape of the optical fiber bundle is circular, wavy, rectangular or polygonal.

6. The method for reverse beam combining and beam homogenization of optical fiber bundles according to claim 1, characterized in that: Between step 3) and step 4), the method further includes performing light field homogenization processing on the light-transmitting micro-region to improve the light field uniformity in each micro-region.

7. The method for reverse bundling and beam homogenization of optical fiber bundles according to claim 5, characterized in that: The light field homogenization process includes adjusting the arrangement of optical fiber filaments, the diameter of optical fiber filaments or the spacing parameters between optical fiber filaments to achieve light field homogenization in the micro area.

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