Preparation method of optical fiber image transmitting element based on square optical fiber structure
By combining and drawing the square core, cladding and absorbing glass wire, composite fiber filaments are formed and optical fiber screen segments are formed through melting and forming the fiber screen segments, the problem of high difficulty in making the square fiber structure image transmission components in the prior art is solved, and process simplification and efficiency improvement are achieved.
Patent Information
- Application Number
- CN202411977571.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2025-04-11
AI Technical Summary
In the prior art, it is difficult to make optical fiber image transmission elements with square fiber structures, especially the materials supply and production of pentagonal core glass rods and square leather glass tubes.
By obtaining a square core glass rod, a square clad glass wire and a square absorbent glass wire, a square fiber preform rod is combined into a square fiber preform rod, and a composite fiber filament is drawn to form multiple times, and finally, the fourth preset side length optical fiber screen segment is formed by melting and compression.
It reduces the difficulty of making fiber image transmission components with square fiber structures, simplifies the process flow, and avoids the use of difficult materials.
Smart Images
Figure CN119797745A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of optical fiber preparation, and in particular to a method for preparing an optical fiber imaging element based on a square optical fiber structure. Background Art
[0002] The optical fiber panel is a rigid optical fiber image transmission element made of tens of millions of optical fibers with a diameter of 4-6μm through regular arrangement, melt pressing and optical cold processing. At present, the structure of a single optical fiber mainly includes two types: circular and square. It is widely used in low-light night vision, aerospace and optoelectronic detection. Among them, the optical fiber image transmission element is used to couple with CCD (charge coupled device), and is widely used in low-light imaging, high-speed photography and X-ray imaging. The optical fiber image transmission element with a square optical fiber structure is consistent with the photosensitive unit of CCD, and has the advantage of high matching efficiency compared to the circular optical fiber structure. In addition, the regular polygonal optical fiber structure has the advantage of no gaps and no sawtooth in the optical fiber combination compared to the circular optical fiber structure, which can reduce the defects of optical fiber transmission such as the frame and black spots caused by matching defects.
[0003] In the relevant process scheme, such as Figure 1 As shown in (a), a pentagonal core glass rod is prepared and matched with a square skin glass tube to form an optical fiber preform rod, which is then drawn into a single optical fiber filament of a corresponding structure, and then multiple optical fiber preform rods are combined with black absorption glass to form Figure 1 In the structure of (b), P1 represents core glass, P2 represents skin glass, and P1 represents black absorbing glass. The production of pentagonal core glass rods and square skin glass tubes requires high material supply for the rods and tubes and is difficult to produce. Summary of the invention
[0004] In view of this, in order to solve one of the above problems, an embodiment of the present invention aims to provide a method for preparing an optical fiber imaging element based on a square optical fiber structure, which can reduce the difficulty of manufacturing an optical fiber imaging element with a square optical fiber structure.
[0005] An embodiment of the present invention provides a method for preparing an optical fiber imaging element based on a square optical fiber structure, comprising:
[0006] Obtain a square core glass rod, a square cladding glass filament, and a square absorption glass filament;
[0007] Arrange the core glass rod, a plurality of the cladding glass fibers and a plurality of the absorbing glass fibers to obtain a square optical fiber preform; the core glass rod is wrapped with the cladding glass fibers, and the absorbing glass fibers are distributed around the cladding glass fibers and at the four corners of the optical fiber preform;
[0008] Drawing the optical fiber preform into a square single optical fiber filament with a first preset side length, and drawing a plurality of the square single optical fiber filaments into a square primary composite optical fiber filament with a second preset side length;
[0009] A plurality of the square primary composite optical fiber filaments are drawn into square secondary composite optical fiber filaments with a third preset side length, and a plurality of the square secondary composite optical fiber filaments are melt-pressed into optical fiber screen segments with a fourth preset side length.
[0010] Optionally, the preparation method further comprises:
[0011] A square core glass filament is obtained, and the core glass filament is arranged between the core glass rod and the cladding glass filament.
[0012] Optionally, the square cladding glass yarn is prepared by the following method:
[0013] The square cladding glass rod is heated to a first preset temperature until it softens and is drawn into a square cladding glass wire.
[0014] Optionally, the side length of the absorbing glass filaments satisfies the following relationship:
[0015]
[0016] Wherein, L1 represents the side length of the absorption glass filament, L2 represents the side length of the optical fiber preform rod, and L3 represents the side length of the core glass rod.
[0017] Optionally, drawing the optical fiber preform into a square single optical fiber filament with a first preset side length comprises:
[0018] The optical fiber preform is heated to a second preset temperature until it softens, and is drawn into a square single optical fiber filament with a first preset side length under a vacuum environment.
[0019] Optionally, drawing a plurality of the square single optical fiber filaments into a square primary composite optical fiber filament with a second preset side length comprises:
[0020] Arrange a plurality of the square single optical fibers in a square shape, heat to a third preset temperature until softened, and draw into a square primary composite optical fiber with a second preset side length under a vacuum environment.
[0021] Optionally, drawing a plurality of square primary composite optical fiber filaments into square secondary composite optical fiber filaments with a third preset side length comprises:
[0022] Arrange a plurality of square primary composite optical fiber filaments in a square shape, heat them to a fourth preset temperature until they soften, and draw them into square secondary composite optical fiber filaments with a third preset side length under a vacuum environment.
[0023] Optionally, the step of melting and pressing a plurality of the secondary composite optical fiber filaments into an optical fiber screen segment with a fourth preset side length comprises:
[0024] Arrange a plurality of the secondary composite optical fiber filaments in a square shape, heat to a fifth preset temperature until softened, and apply a preset pressure in a vacuum environment to draw them into an optical fiber screen segment with a fourth preset side length.
[0025] Optionally, the vacuum degree of the vacuum environment is above -0.08 MPa.
[0026] Optionally, the preset pressure ranges from 6 to 12 MPa.
[0027] The implementation of the embodiment of the present invention includes the following beneficial effects: the embodiment of the present invention first arranges a square core glass rod, a plurality of square cladding glass fibers and a plurality of square absorption glass fibers to obtain a square optical fiber preform, the outer periphery of the core glass rod is wrapped with cladding glass fibers, the absorption glass fibers are distributed on the outer periphery of the cladding glass fibers and at the four corners of the optical fiber preform, and then the optical fiber preform is drawn into a square single optical fiber, and multiple composite optical fiber fibers are drawn based on the square single optical fiber, and finally the composite optical fiber is melt-pressed into an optical fiber screen segment with a fourth preset side length, and during the preparation process, there is no need to make a pentagonal core glass rod and a square skin glass tube, thereby reducing the difficulty of making an optical fiber imaging element with a square optical fiber structure. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Figure 1 It is a schematic diagram of the structure of an optical fiber preform and an optical fiber image transmission element in the related art;
[0029] Figure 2 It is a schematic flow chart of the steps of a method for preparing an optical fiber imaging element based on a square optical fiber structure provided by an embodiment of the present invention;
[0030] Figure 3 is a schematic structural diagram of a square optical fiber preform provided by an embodiment of the present invention;
[0031] Figure 4 is a schematic structural diagram of another square optical fiber preform provided by an embodiment of the present invention;
[0032] Figure 5 It is a flow chart of drawing a square single optical fiber provided by an embodiment of the present invention;
[0033] Figure 6 is another flow chart of drawing a square single optical fiber provided by an embodiment of the present invention;
[0034] Figure 7This is a flow chart of drawing a square primary composite optical fiber provided by an embodiment of the present invention;
[0035] Figure 8 It is a structural schematic diagram of an optical fiber imaging element based on a square optical fiber structure provided by an embodiment of the present invention. DETAILED DESCRIPTION
[0036] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The step numbers in the following embodiments are only provided for the convenience of explanation and description, and the order between the steps is not limited in any way. The execution order of each step in the embodiment can be adaptively adjusted according to the understanding of those skilled in the art.
[0037] like Figure 2 As shown, an embodiment of the present invention provides a method for preparing an optical fiber imaging element based on a square optical fiber structure, comprising:
[0038] S100, obtaining a square core glass rod, a square cladding glass filament, and a square absorption glass filament.
[0039] The refractive index of the core glass rod is greater than the refractive index of the cladding glass filament. The square core glass rod can be made from the core glass, the square cladding glass filament can be made from the cladding glass, and the square absorption glass filament can be made from the black absorption glass.
[0040] Alternatively, square cladding glass yarns are prepared by the following method:
[0041] The square cladding glass rod is heated to a first preset temperature until it softens and is drawn into a square cladding glass wire.
[0042] The first preset temperature is determined according to the actual application, for example, the first preset temperature is set to the softening temperature of the cladding glass. The side length of the cladding glass filament is determined according to the actual application. Similarly, the core glass is heated to the softening temperature of the core glass and then drawn into a required square core glass rod; the absorbent glass is heated to the softening temperature of the absorbent glass and then drawn into a required square absorbent glass filament.
[0043] S200, arranging a core glass rod, a plurality of cladding glass fibers and a plurality of absorbing glass fibers to obtain a square optical fiber preform; the core glass rod is wrapped with the cladding glass fibers, and the absorbing glass fibers are distributed around the cladding glass fibers and at the four corners of the optical fiber preform.
[0044] See also Figure 3 , Figure 3The schematic diagram of the structure of an optical fiber preform is shown, N1 represents the core glass rod, N2-1 represents the square cladding glass filament of the first side length, N2-2 represents the square cladding glass filament of the second side length, and N3 represents the absorption glass filament. The outer periphery of the core glass rod is wrapped with the cladding glass filament, and the absorption glass filament is distributed at the four corners of the optical fiber preform.
[0045] The optical fiber preform rod includes a core glass rod, a cladding glass fiber and a black absorption glass fiber. The core glass is a high-refractive-index glass, and the cladding glass is a low-refractive-index glass, which enables light to be transmitted by total reflection in the optical fiber. The black absorption glass is used to absorb stray light propagating in the optical fiber imaging element and improve the contrast of the image transmitted by the optical fiber imaging element.
[0046] S300, drawing the optical fiber preform into a square single optical fiber filament with a first preset side length, and drawing a plurality of square single optical fiber filaments into a square primary composite optical fiber filament with a second preset side length.
[0047] First, the assembled optical fiber preform is drawn into a square single optical fiber filament with a first preset side length, and then a plurality of square single optical fiber filaments are arranged and drawn into a square primary composite optical fiber filament with a second preset side length. The second preset side length is determined according to actual application.
[0048] S400, drawing a plurality of square primary composite optical fiber filaments into square secondary composite optical fiber filaments with a third preset side length, and melting and pressing a plurality of square secondary composite optical fiber filaments into optical fiber screen segments with a fourth preset side length.
[0049] First, according to product requirements, the square primary composite optical fiber filaments can be composited multiple times, such as arranging a plurality of square primary composite optical fiber filaments and drawing them into square secondary composite optical fiber filaments with a third preset side length; then, arranging a plurality of square secondary composite optical fiber filaments and melting and pressing them into optical fiber screen segments with a fourth preset side length. The third preset side length and the fourth preset side length are determined according to actual applications.
[0050] Optionally, the preparation method further comprises:
[0051] A square core glass filament is obtained and the core glass filament is arranged between the core glass rod and the cladding glass filament.
[0052] See also Figure 4 , Figure 4 The schematic diagram of the structure of another optical fiber preform is shown, N1 represents a core glass rod, N1-1 represents a core glass filament, N2 represents a square cladding glass filament, and N3 represents an absorption glass filament. The periphery of the core glass rod is wrapped with a core glass filament, the periphery of the core glass filament includes a cladding glass filament, and the absorption glass filament is arranged at the four corners of the optical fiber preform.
[0053] Optionally, the side length of the absorbing glass yarn satisfies the following relationship:
[0054]
[0055] Wherein, L1 represents the side length of the absorbing glass filament, L2 represents the side length of the optical fiber preform rod, and L3 represents the side length of the core glass rod.
[0056] See also Figure 3 and Figure 4 The side length of the absorbing glass fiber is determined according to the structure of the core glass rod and the optical fiber preform and other related factors.
[0057] Optionally, drawing the optical fiber preform into a square single optical fiber filament with a first preset side length comprises:
[0058] The optical fiber preform is heated to a second preset temperature until it softens, and is drawn into a square single optical fiber filament with a first preset side length under a vacuum environment.
[0059] The difference in softening temperature of the core glass, cladding glass and black absorption glass should be controlled within 100°C. When they are combined and heated, they soften and deform, which can meet normal drawing. That is, the second preset temperature is determined based on the temperatures of multiple glasses in the optical fiber preform.
[0060] According to the softening temperature of the optical fiber preform, the heating furnace is set to the corresponding heating temperature, and the optical fiber preform is heated to soften. The heating temperature should be 30-60℃ higher than the highest softening point of the three types of glass: core glass, cladding glass and black absorption glass. The interior of the square optical fiber preform is evacuated, and then drawn and shrunk to form a square single optical fiber. Figure 5 and Figure 6 , Figure 5 and Figure 6 They represent square single optical fiber filaments drawn from two types of optical fiber preform rods.
[0061] Optionally, drawing a plurality of square single optical fiber filaments into a square primary composite optical fiber filament with a second preset side length comprises:
[0062] A plurality of square single optical fibers are arranged in a square shape, heated to a third preset temperature until softened, and drawn into a square primary composite optical fiber with a second preset side length under a vacuum environment.
[0063] Arrange square single optical fibers into a square composite optical fiber rod. The number of single optical fibers on each side is not required, but the length and width must be the same to ensure a square structure. Figure 7, M1 represents a square single optical fiber, M2 represents a square primary composite optical fiber, the square primary composite optical fiber rod is hung on the drawing equipment, and the heating furnace is set to the corresponding heating temperature according to the softening temperature of the glass optical fiber. The heating temperature should be 30-60℃ higher than the highest softening point of the three types of glass: core glass, cladding glass and black absorption glass. The single optical fiber is softened by heating, and the interior of the single optical fiber is vacuumed, and then drawn into a thin square primary composite optical fiber.
[0064] Optionally, drawing a plurality of square primary composite optical fiber filaments into square secondary composite optical fiber filaments with a third preset side length comprises:
[0065] A plurality of square primary composite optical fiber filaments are arranged in a square, heated to a fourth preset temperature until softened, and drawn into square secondary composite optical fiber filaments with a third preset side length under a vacuum environment.
[0066] Arrange the square primary composite optical fiber filaments in a square shape. There is no requirement for the number of single optical fibers on each side, but the length and width must be the same to ensure a square structure. Hang the arranged primary composite optical fiber rods on the drawing equipment. Set the heating furnace to the corresponding heating temperature according to the softening temperature of the glass optical fiber. The heating temperature should be 30-60℃ higher than the highest softening point of the three types of glass: core glass, cladding glass and black absorption glass. Heat to soften the single optical fiber filament, evacuate the interior of the single optical fiber filament, and then draw it into a thin square secondary composite optical fiber filament.
[0067] Optionally, a plurality of secondary composite optical fiber filaments are melt-pressed into an optical fiber screen segment with a fourth preset side length, comprising:
[0068] Arrange a plurality of secondary composite optical fiber filaments in a square shape, heat to a fifth preset temperature until softened, and apply a preset pressure in a vacuum environment to draw them into an optical fiber screen segment with a fourth preset side length.
[0069] Arrange the drawn square secondary composite optical fiber filaments into square screen segments and place them into the corresponding melting and pressing molds. Perform vacuum high-temperature heating in the melting and pressing furnace and apply pressure. The corresponding temperature should be set according to the softening temperature of the glass. The heating temperature should be 20-50℃ higher than the lowest softening point of the core glass and cladding glass. Heat until the optical fiber becomes soft, the vacuum degree reaches the preset requirements, and the pressure is applied to meet the preset requirements, so that the square composite optical fiber filaments are bonded to each other to form an integrated optical fiber screen segment.
[0070] Optionally, the vacuum degree of the vacuum environment is above -0.08 MPa.
[0071] Optionally, the preset pressure ranges from 6-12 MPa.
[0072] During the drawing process, the vacuum environment and the preset pressure are determined according to the actual application, and this embodiment does not impose any specific restrictions.
[0073] The preparation of an optical fiber imaging element based on a square optical fiber structure is described below using a specific embodiment.
[0074] S1. Processing of optical fiber preform materials: core glass with a refractive index of 1.8, cladding glass with a refractive index of 1.5 and black absorption glass are selected and made into square glass rods with a side length of 15mm×15mm and a length of 500mm; on the drawing equipment, they are drawn into square glass fibers with a side length of 1.25mm×1.25mm and a length of 500mm. Among them, the softening temperature of the core glass is 730℃, the softening temperature of the cladding glass is 690℃, and the softening temperature of the black absorption glass is 685℃.
[0075] S2. Optical fiber preform rod combination: use 1 square core glass rod with a side length of 15mm×15mm, 60 square skin glass fibers with a side length of 1.25mm×1.25mm, 48 square core glass fibers with a side length of 1.25mm×1.25mm, and 4 square black absorption glass fibers with a side length of 1.25mm×1.25mm, and arrange them into the following combinations: Figure 4 An optical fiber preform with a side length of 20mm×20mm and a length of 500mm.
[0076] S3. Drawing of square single optical fiber: hang the assembled optical fiber preform rod with a side length of 20mm×20mm and a length of 500mm on the optical fiber drawing equipment, set the temperature of the heating furnace to between 760-790℃, heat to soften the optical fiber preform rod, and evacuate the interior of the square optical fiber preform rod to a vacuum degree of more than -0.08MPa, then draw and shrink it to draw it into a square single optical fiber filament with a side length of 1.5mm×1.5mm and a length of 500mm.
[0077] S4. Arrangement and drawing of primary composite optical fiber rod: Arrange 144 square single optical fiber filaments with a side length of 1.5mm×1.5mm into a square primary composite optical fiber rod with a side length of 18mm×18mm and a length of 500mm. Hang the square primary composite optical fiber rod with a side length of 18mm×18mm and a length of 500mm on the drawing equipment, set the heating furnace temperature to between 760-790℃, heat to soften the optical fiber preform rod, and evacuate the interior of the square optical fiber preform rod to a vacuum degree of more than -0.08MPa, and then draw and shrink it into a square primary composite optical fiber filament with a side length of 1mm×1mm and a length of 500mm.
[0078] S5. Arrangement and drawing of secondary composite optical fiber rods: Arrange 400 square primary composite optical fiber filaments with a side length of 1mm×1mm into a square secondary composite optical fiber rod with a side length of 20mm×20mm and a length of 500mm. Hang the square secondary composite optical fiber rod with a side length of 20mm×20mm and a length of 500mm on the drawing equipment, set the heating furnace temperature to between 760-790℃, heat to soften the optical fiber preform, and evacuate the interior of the square optical fiber preform to a vacuum degree of more than -0.08MPa, and then draw it into a square secondary composite optical fiber filament with a side length of 1.5mm×1.5mm and a length of 100mm.
[0079] S6. Screen segment arrangement and melting and pressing: Arrange 400 square secondary composite optical fiber filaments with a side length of 1.5mm×1.5mm and a length of 100mm into a square screen segment with a side length of 30mm×30mm and a length of 100mm, and place them into corresponding melting and pressing molds, and perform vacuum high-temperature heating in a melting and pressing furnace, wherein the temperature is set between 710-740℃, the vacuum degree must be ensured to be above -0.08MPa, and a pressure of 10MPa is applied to press and fuse them into an optical fiber screen segment with a side length of 28.5mm×28.5mm, to obtain an optical fiber imaging element blank with a single optical fiber size of a square optical fiber structure with a side length of 6μm×6μm.
[0080] S7. Product shape processing: According to the product size requirements, the square optical fiber structure optical fiber image transmission element blank is processed to produce the square optical fiber structure optical fiber image transmission element with the required size. Figure 8 , Q1 represents the core, Q2 represents the cortex, and Q3 represents the black absorption glass. Each optical fiber image transmission element is composed of tens of millions of 6μm×6μm square single optical fibers. Among them, the optical fiber image transmission element can be processed into square, circular, polygonal and other shapes according to the appearance requirements of the product without affecting the square structure of the single optical fiber inside.
[0081] The implementation of the embodiment of the present invention includes the following beneficial effects: the embodiment of the present invention first arranges a square core glass rod, a plurality of square cladding glass fibers and a plurality of square absorption glass fibers to obtain a square optical fiber preform, the outer periphery of the core glass rod is wrapped with cladding glass fibers, the absorption glass fibers are distributed on the outer periphery of the cladding glass fibers and at the four corners of the optical fiber preform, and then the optical fiber preform is drawn into a square single optical fiber, and multiple composite optical fiber fibers are drawn based on the square single optical fiber, and finally the composite optical fiber is melt-pressed into an optical fiber screen segment with a fourth preset side length, and during the preparation process, there is no need to make a pentagonal core glass rod and a square skin glass tube, thereby reducing the difficulty of making an optical fiber imaging element with a square optical fiber structure.
[0082] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.
Claims
1. A method for preparing an optical fiber imaging element based on a square optical fiber structure, characterized in that: include: Obtain a square core glass rod, a square cladding glass filament, and a square absorption glass filament; Arrange the core glass rod, a plurality of the cladding glass fibers and a plurality of the absorbing glass fibers to obtain a square optical fiber preform; the core glass rod is wrapped with the cladding glass fibers, and the absorbing glass fibers are distributed around the cladding glass fibers and at the four corners of the optical fiber preform; Drawing the optical fiber preform into a square single optical fiber filament with a first preset side length, and drawing a plurality of the square single optical fiber filaments into a square primary composite optical fiber filament with a second preset side length; A plurality of the square primary composite optical fiber filaments are drawn into square secondary composite optical fiber filaments with a third preset side length, and a plurality of the square secondary composite optical fiber filaments are melt-pressed into optical fiber screen segments with a fourth preset side length.
2. The preparation method according to claim 1, characterized in that: The preparation method further comprises: A square core glass filament is obtained, and the core glass filament is arranged between the core glass rod and the cladding glass filament.
3. The preparation method according to claim 1, characterized in that: The square cladding glass yarn is prepared by the following method: The square cladding glass rod is heated to a first preset temperature until it softens and is drawn into a square cladding glass wire.
4. The preparation method according to claim 1, characterized in that: The side length of the absorbing glass filaments satisfies the following relationship: Wherein, L1 represents the side length of the absorption glass filament, L2 represents the side length of the optical fiber preform rod, and L3 represents the side length of the core glass rod.
5. The preparation method according to claim 1, characterized in that: The step of drawing the optical fiber preform into a square single optical fiber filament with a first preset side length comprises: The optical fiber preform is heated to a second preset temperature until it softens, and is drawn into a square single optical fiber filament with a first preset side length under a vacuum environment.
6. The preparation method according to claim 1, characterized in that: Drawing a plurality of the square single optical fiber filaments into a square primary composite optical fiber filament with a second preset side length, comprising: Arrange a plurality of the square single optical fibers in a square shape, heat to a third preset temperature until softened, and draw into a square primary composite optical fiber with a second preset side length under a vacuum environment.
7. The preparation method according to claim 1, characterized in that: Drawing a plurality of square primary composite optical fiber filaments into square secondary composite optical fiber filaments with a third preset side length comprises: Arrange a plurality of square primary composite optical fiber filaments in a square shape, heat them to a fourth preset temperature until they soften, and draw them into square secondary composite optical fiber filaments with a third preset side length under a vacuum environment.
8. The preparation method according to claim 1, characterized in that: The method of melting and pressing a plurality of the secondary composite optical fiber filaments into an optical fiber screen segment of a fourth preset side length comprises: Arrange a plurality of the secondary composite optical fiber filaments in a square shape, heat to a fifth preset temperature until softened, and apply a preset pressure in a vacuum environment to draw them into an optical fiber screen segment with a fourth preset side length.
9. The preparation method according to any one of claims 5 to 8, characterized in that: The vacuum degree of the vacuum environment is above -0.08 MPa.
10. The preparation method according to claim 8, characterized in that: The preset pressure ranges from 6 to 12 MPa.