Partitioned weaving and light beam uniformity adjusting method of optical fiber bundle

Abstract

The invention discloses a method for zoning weaving of an optical fiber bundle and adjusting uniformity of a light beam. For a branched optical fiber bundle, a light source (or an incident end cross section) can be divided into sub-zones according to the light beam quality of the used light source, the diameter of the optical fiber, the number of branches and the required homogenization degree, and the sub-zones are further subdivided into a plurality of micro-zones. Each micro-area is composed of a small beam of optical fibers, and the purpose of adjusting the uniformity of light beams is achieved by adjusting and controlling the size and the number of the micro-areas. The method is suitable for manufacturing one-to-many and many-to-many optical fiber bundles, and has wide applicability and technical value. According to the method, the light beam uniformity of the optical fiber bundle is improved, the mechanical strength and stability of the optical fiber bundle are enhanced, and the requirements of different fields for the light beam uniformity of the optical fiber bundle are met.

Description

Technical Field

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

[0002] Fiber optic bundles are products made by bundling multiple optical fibers. They can be used to transmit energy and images. They have a large number of product application examples in the fields of laser medicine, energy detection, ultraviolet lithography, quality inspection, etc. and have good development prospects.

[0003] The light source required to be transmitted by the optical fiber bundle is usually a non-homogeneous light source, and it is hoped that it will become a homogenized light beam after being transmitted through the optical fiber bundle. In the process of making branched light-guiding fiber bundles on the market, in order to make up for the lack of uniformity of the light source itself and improve the uniformity of the light field distribution at the light output end, the traditional solution is to randomly weave the optical fiber, that is, to scatter the optical fiber filaments at one end of the optical fiber bundle for mixing, and to disrupt the spatial arrangement of the optical fiber so that the position relationship between the optical fiber at the light input end and the optical fiber at the light output end does not correspond one to one, thereby achieving the effect of light beam homogenization. However, this solution has certain limitations: on the one hand, the uncertainty of random weaving is very large, resulting in large changes in the beam quality, no feedback iteration, and difficult to optimize and improve. Therefore, it is easy to cause insufficient fiber homogenization. When the uniformity of the output light field cannot be guaranteed, it is often necessary to add an optical homogenizer before the light input end or after the output end to homogenize and shape the light beam, which will increase the complexity of the system; on the other hand, random weaving is also prone to unnecessary excessive scattering and mixing, which is a huge workload and also easily causes an increase in the broken wire rate and reduces efficiency. When applied to product production lines, there is no quantifiable and effective means to control the uniformity of the output light field of the optical fiber bundle, which will greatly reduce the product yield and increase production costs. Summary of the invention

[0004] In order to overcome the deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide a method for partitioning and braiding of an optical fiber bundle and adjusting the uniformity of the light beam. For branch optical fiber bundles of single-to-multiple or multi-to-multiple types, the present invention can perform partitioning and weaving and micro-area construction according to the beam quality of the incident light source and the required homogenization effect. First, the light field of the micro-area is homogenized, and then the numerous micro-areas are arranged and combined into the required end face shape of the optical fiber bundle to improve the uniformity of the light field distribution of the entire light output end face, making up for the problem of insufficient illumination uniformity caused by the optical fiber filaments not being arranged, arranged in disorder, and scattered and randomly arranged when the light source beam quality used is not good, and the uniformity can be adjusted by adjusting the number and size of micro-areas. The uniformity requirements of high-power devices can be met. The method proposed in the present invention can quantitatively determine the specific weaving process according to the light source beam quality and the required homogenization effect of the output light field.

[0005] The technical solution of the present invention is as follows:

[0006] A method for partitioning and braiding an optical fiber bundle and adjusting the uniformity of the optical beam, wherein the method comprises the following steps:

[0007] 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, the cladding is made of glass or other materials with a refractive index lower than that of the core material, and the optical fiber coating is made of a colored material

[0008] 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 later use, and then braided and bundled.

[0009] 3) First, the light source (or the incident end cross section) is partitioned based on the beam quality of the light source into n equal-area sub-areas S, and the sub-areas are numbered 1, 2, 3, ... n. The optical fibers constituting each sub-area are distinguished by different coating colors.

[0010] 4) Each sub-area is further divided into M micro-areas. M is a multiple of N, M is greater than or equal to N, and N is the number of branches. In the same sub-area, the maximum and minimum power difference is ΔP, and the difference is expressed as a percentage. The size of the micro-area depends on the optical power difference of the sub-area. The larger ΔP is, the smaller the corresponding micro-area needs to be, and the smaller ΔP is, the larger the corresponding micro-area needs to be.

[0011] The size of the micro-zone is also determined by the beam quality of the light source used, the diameter of the optical fiber, and the required degree of homogenization. In order to facilitate the construction of the micro-zone, it is first necessary to determine the definition of the homogenization effect: the power ratio of any two small areas of equal area on the output end face of the optical fiber beam (i.e., the power ratio described by the homogenization effect) φp. The closer this value is to 1, the better the homogenization effect.

[0012] The specific size of the micro-region depends on the required homogenization effect φp and ΔP.

[0013] Afterwards, based on the partitioning plan of the light source (or the incident end cross section), n sub-partitions of equal area are divided at the branch end, and each area is numbered 1, 2, 3, ... n, corresponding to the n sub-areas of the incident end. The sub-area numbered 1 corresponds to the incident end sub-area No. 1, and the sub-area numbered n corresponds to the incident end sub-area No. n. In each sub-area, multiple micro-areas from the corresponding sub-area can be arranged.

[0014] a) In the above-mentioned several equal-area sub-areas S, if the energy in a single area changes dramatically, the micro-area taken in the area needs to be further reduced;

[0015] b) The sub-areas S of equal area do not need to be of the same shape;

[0016] c) The smaller the diameter of the optical fiber, the smaller the micro-region that can be achieved;

[0017] 5) The above-mentioned micro-area can be fixed by bundling multiple optical fibers, and the optical fiber end face of the micro-area can be constructed into circular, wavy, rectangular, polygonal and other shapes as needed. In order to facilitate the arrangement and assembly of the micro-area at the branch end, the shape of the micro-area generally depends on the shape of the branch end. If the branch is circular, the micro-area is a hexagonal sub-bundle (the number of optical fibers in the micro-area is 7, 19, 37, 61...); if the branch is square, the micro-area is also square. If the end face optical fiber needs to be tightly packed with hexagons in order to achieve the goal of high transmittance of the optical fiber bundle, the micro-area should be a hexagonal sub-bundle.

[0018] 6) The optical fibers are scattered and braided at one end of the optical fiber bundle. The length of the braided area is generally 400-500mm, and the braiding length can be increased according to actual needs.

[0019] 7) 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 at the optical fiber bundle output end, arrange them according to the sub-region numbers, and bundle them into the entire end face.

[0020] The braiding operation is characterized in that the plurality of sub-bundles of optical fibers constituting the light-transmitting micro-regions are dispersed and mixed.

[0021] 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.

[0022] The present invention is suitable for the production of one-to-many and many-to-many optical fiber bundles.

[0023] The manufacturing steps of the present invention are to first manufacture the light input end and then manufacture the light output end.

[0024] Compared with the prior art, the technical effects of the present invention are:

[0025] The present invention provides a method for partitioning and braiding an optical fiber bundle and adjusting the uniformity of the light beam. In the production of a branch optical fiber bundle, it is innovatively proposed to divide the optical fiber incident end face into sub-areas and micro-areas according to the beam quality of the light source, and to braid the micro-area sub-bundles and arrange and bundle the micro-area sub-bundles at the branch end. The method is simple, convenient and easy to implement. Compared with the traditional scheme, it further optimizes the uniformity of the light field distribution at the branch end of the optical fiber bundle, and the uniformity of the light field distribution can be adjusted by adjusting the size and number of micro-areas. The light source (or the incident end cross section) is divided into sub-areas and micro-areas according to the beam quality of the incident light source, the diameter of the optical fiber and the required degree of homogenization; the optical fiber is scattered and braided at one end of the optical fiber bundle, and each micro-area is arranged on the light exit end face according to the corresponding sub-area number to form the required end face shape. The uniformity of the light beam can be adjusted by adjusting the size and number of micro-areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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.

[0027] Figure 1 This is a schematic diagram of the end face of the constructed hexagonal light-transmitting micro-region.

[0028] Figure 2 Schematic diagram of the braiding operation framework of the one-to-three optical fiber bundle in the embodiment

[0029] Figure 3 This is a schematic diagram of the spot energy distribution of the light source used

[0030] Figure 4 Schematic diagram of sub-areas divided in the embodiment

[0031] Figure 5 This is a schematic diagram of the branch terminal partition division

[0032] Figure 6 Schematic diagram of the process of combining and weaving a one-to-three optical fiber bundle in an embodiment

[0033] Figure 7 Schematic diagram of the incident end face of the optical fiber bundle

[0034] Throughout the drawings, reference numerals are used to designate various elements and structures, wherein:

[0035] 1- Single optical fiber that makes up a micro-zone

[0036] 2-Incoming end of one-to-three fiber bundle

[0037] 3-Incident end fixing fixture

[0038] 4-Inner diameter shrink ring

[0039] 5-Branch end of one-to-three fiber bundle

[0040] 6-Fiber optic wire

[0041] 7-Constructed light-transmitting micro-area beam DETAILED DESCRIPTION

[0042] 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.

[0043] An embodiment of the present invention provides a method for partitioning and adjusting the uniformity of a one-to-three optical fiber bundle, wherein the light input end and the light output end of the optical fiber bundle are both circular in shape, and the method comprises the following steps:

[0044] 1) Take a batch of 10km long optical fibers, the core material is pure quartz, the cladding material is fluorine-doped quartz, the outer diameter of the bare fiber is 190μm, and the coating is made of colored material

[0045] 2) Cut the optical fibers into 1500±100mm lengths, a total of about 6666 fibers can be cut. One end of the optical fiber is fixed into a circular incident end face shape through a mold. The incident end face is as follows: Figure 7 Shown

[0046] 3) Place the entire fiber bundle vertically in a Figure 2 The incident end is fixed with a fixing fixture on the braiding operation frame shown in the figure.

[0047] 4) According to Figure 3 The incident light spot energy distribution shown in FIG. 1 divides the incident end face of the fiber bundle into 8 sub-areas of equal area. The sub-areas are shaped like a central circle and 7 surrounding rings of equal area, numbered 1, 2, 3, ... 8. The schematic diagram of the sub-area division is shown in FIG. Figure 4 As shown. In the same sub-area, the maximum and minimum power difference is ΔP, and the difference is expressed as a percentage. The larger the ΔP, the smaller the corresponding micro-area needs to be, and the smaller the ΔP, the larger the corresponding micro-area needs to be. The fiber coating color of each sub-area is different to distinguish

[0048] 5) Before the formal micro-area construction and weaving, the homogenization effect to be achieved is first determined. The definition of the homogenization effect in this embodiment is: the power ratio (i.e., the power ratio described in the homogenization effect) φp in any two circular areas with a diameter of 4 mm on the optical fiber bundle exit end face. The closer this value is to 1, the better the homogenization effect. The homogenization effect to be achieved in this embodiment is 0.95≤φp≤1.05.

[0049] 6) In this embodiment, the output end face of the one-to-three optical fiber bundle is circular. In order to achieve the goal of high transmittance of the optical fiber bundle, the optical fiber filaments need to be hexagonally densely packed on the end face. At this time, the micro-region is preferably constructed as a hexagonal sub-bundle. The schematic diagram of the micro-region end face is shown in FIG. Figure 1 shown.

[0050] 7) Based on the partitioning plan of the incident end face of the optical fiber bundle, 8 sub-partitions of equal area are divided at the branch end, and each area is numbered 1, 2, 3, ... 8. In each sub-partition, multiple micro-areas from the corresponding sub-area can be arranged. The sub-partition numbered 1 corresponds to the thick end sub-area 1, and the sub-partition numbered 8 corresponds to the thick end sub-area 8. The 18273645 areas in the optical fiber bundle exit end face are arranged in sequence, as shown in the schematic diagram Figure 5 Shown

[0051] 8) Determination of the number of optical fibers in a micro-area: In the eight sub-areas divided by the incident end face of the optical fiber bundle, Figure 3 In the energy distribution of the incident light spot shown in the figure, the ΔP in the circular sub-area No. 1 is the largest, which is 40%. At this time, in order to achieve a given homogenization effect, that is, on the optical fiber bundle exit end face, the power ratio in any two circular areas with a diameter of 4 mm is 0.95≤φp≤1.05. At the same time, considering that the outer diameter of the cladding of the optical fiber used is 190μm, the number of optical fibers in a single micro-area in the No. 1 sub-area is preferably 19. The number of optical fibers in the micro-areas of the other 7 sub-areas x is based on Sure.

[0052] 9) In this embodiment, the location of the micro-zone is 100mm-150mm away from the incident end to avoid problems such as fiber breakage caused by too small a micro-zone area and increased fiber loss caused by too small a fiber bending radius.

[0053] 10) After the micro-areas in each sub-area are constructed, they are woven within a range of 150mm-500mm from the incident end, as shown in the schematic diagram. Figure 6 Shown

[0054] 11) Pass the other end of the constructed micro-area sub-bundle through Figure 2 The inner diameter shrinking ring shown in the figure has 3 circular inner rings, the size of which can be freely adjusted and can be moved in the vertical direction.

[0055] 12) Figure 2 The inner circle size of the shrink ring is adjusted to 15mm in diameter, so that the optical fiber passing through it gradually converges into a circle, and the height of the shrink ring is adjusted to 800mm-900mm from the bottom of the optical fiber.

[0056] 13) The optical fiber coating of each sub-area is colored with different colors of paint to distinguish the micro-area sub-bundles from different sub-areas. The light-transmitting micro-area head ends constructed with the above size and shape are aligned and placed in a mold matching the light-transmitting area of ​​the optical fiber bundle output end, and arranged according to the sub-area number to bundle into the entire end face.

[0057] 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 partitioning and braiding an optical fiber bundle and adjusting the uniformity of the optical beam, characterized in that: The method comprises the following steps: 1) Preparation of optical fiber materials: Provide optical fiber, including a core and a cladding, and the refractive index of the core is higher than the refractive index of the cladding; 2) Fiber cutting and braiding: 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 corresponding parts in equal amounts, and the cut optical fibers are braided; 3) Light source partitioning and fiber coloring: Based on the beam quality of the light source, the light source or the incident end cross section is divided into n equal-area sub-areas S, and each sub-area is numbered 1, 2, 3, ... n, n ≥ 2, and different coating colors are used to color the optical fiber constituting each sub-area; 4) Micro-area division and power balancing: Each sub-area is further divided into M micro-areas, where M is a multiple of N and M is greater than or equal to N, and N is the number of branches. Within the same sub-area, the size of the micro-area is determined by the optical power difference ΔP of the sub-area and the required degree of homogenization: The larger the maximum and minimum power difference ΔP in the sub-area, the smaller the corresponding micro-area size needs to be. Conversely, the smaller the optical power difference ΔP is, the larger the corresponding micro-area size needs to be. The homogenization effect is measured by the power ratio φp of any two micro-regions of equal area on the output end face of the optical fiber bundle. The closer φp is to 1, the better the homogenization effect. 5) Dispersed braiding of optical fiber bundles: The optical fibers are dispersed and braided at one end of the optical fiber bundle. The length of the braided area can be adjusted according to actual needs, generally 400-500mm; 6) Micro-area arrangement and bundling: Align the light-transmitting micro-area heads with good size and shape and place them in a mold that matches the light-transmitting area at the output end of the optical fiber bundle, arrange them according to the sub-area numbers, and bundle them into the entire end face.

2. The method for partitioned braiding of optical fiber bundles and adjustable beam uniformity according to claim 1, characterized in that: The micro-area is fixed by bundling a plurality of optical fibers, and the shape can be constructed into a circle, a wave, a rectangle, or a polygon as required.

3. The method for partitioned braiding of optical fiber bundles and adjustable beam uniformity according to claim 2, characterized in that: The shape of the micro-region depends on the shape of the branch end. If the branch is circular, the micro-region is a hexagonal sub-bundle, and the number of optical fibers in the micro-region is 7, 19, 37, 61...; if the branch is square, the micro-region is also square.

4. The method for partitioned braiding of optical fiber bundles and adjustable beam uniformity according to claim 1, characterized in that: The size of the micro-region is also determined by the beam quality of the light source used and the diameter of the optical fiber.

5. The method for partitioned braiding of optical fiber bundles and adjustable beam uniformity according to claim 4, characterized in that: If there is a dramatic change in the energy in a single area, the micro-area taken in the area needs to be further reduced; the several sub-areas S of equal area do not need to be of the same shape; the smaller the diameter of the optical fiber, the smaller the micro-area that can be achieved.

6. The method for partitioned braiding of optical fiber bundles and adjustable beam uniformity according to claim 1, characterized in that: The material of the mold can be a polymer material or a metal material; or the mold can be omitted and the end face can be manually hooped into the desired shape.

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