An electromagnetic pulse-resistant fiber optic imaging element, its fabrication method, and its application.

Abstract

This invention discloses an electromagnetic pulse (EMP) resistant fiber optic imaging element, its fabrication method, and its application. The method includes: matching a core glass rod and a sheath glass tube and drawing them into a primary monofilament; drawing a metal material as a metal rod into a metal wire; arranging the obtained primary monofilaments in a hexagonal close-packed arrangement, and then arranging the obtained metal wires according to the rules of intermittent insertion, substitution insertion, or a combination of intermittent and substitution insertion to obtain a primary composite rod, and then drawing the primary composite rod into a primary multifilament; arranging the obtained primary multifilaments into a secondary composite rod, drawing the secondary composite rod into a secondary multifilament, and then cutting the secondary multifilaments to a fixed length and arranging them into plate segments; and then performing hot-melt pressing on the obtained plate segments. The technical problem to be solved is that by adding metal wires to the fiber optic imaging element to form an electromagnetic shielding layer, the intrusion of electromagnetic interference such as EMP can be effectively blocked, thereby protecting the signal transmitted in the fiber optic cable from being affected.

Description

Technical Field

[0001] This invention belongs to the field of optical fiber imaging element manufacturing technology, specifically relating to an electromagnetic pulse-resistant optical fiber imaging element, its manufacturing method, and its application. Background Technology

[0002] Fiber optic imaging elements, as important optical devices, have been widely used in defense, scientific research, criminal investigation, and medical fields, playing a particularly important role in high-precision imaging and weak signal detection. With the rapid development of modern digital image processing technology, the combination of fiber optic imaging elements with detectors such as CCDs and CMOS sensors enables the efficient conversion of optical signals into digital signals. This not only performs excellently in traditional visible light imaging but also demonstrates significant advantages in high-energy X-ray imaging, night vision equipment, fingerprint recognition, and high-speed target tracking. In recent years, fiber optic imaging elements have become a key component in applications requiring the enhancement of weak light signals or the processing of X-ray signals. For example, in military, aerospace, and medical fields, high-sensitivity imaging is often required in low-light or even no-light environments, or the detection of extremely weak signals through X-ray imaging. In these situations, fiber optic imaging elements, combined with photomultiplier tubes or image intensifiers, can effectively amplify weak light signals, thereby achieving accurate detection and analysis.

[0003] However, in defense and certain specific scientific research fields, fiber optic imaging components not only need to process weak optical signals but also face complex electromagnetic environment threats, such as electromagnetic pulse (EMP) interference. EMP is a brief but intense electromagnetic wave that can damage electronic equipment and communication systems, thereby affecting equipment performance and data accuracy. In military conflicts or combat environments, EMP attacks can cause serious malfunctions in fiber optic imaging systems, affecting real-time information acquisition and analysis on the battlefield. Therefore, improving the EMP resistance of fiber optic imaging components has become an urgent technical challenge.

[0004] As a transmission medium, optical fiber's transmission characteristics primarily rely on total internal reflection of light within the fiber. Because optical fiber transmits optical signals rather than electrical signals, it possesses a certain degree of resistance to electromagnetic interference (including EMP). However, this resistance is not absolute; optical fiber imaging elements can still be affected by strong EMP interference, leading to decreased transmission performance or failure. Summary of the Invention

[0005] In view of this, the main objective of the present invention is to provide an electromagnetic pulse-resistant fiber optic imaging element, its preparation method and application. The technical problem to be solved is that by adding metal wires to the fiber optic imaging element to form an electromagnetic shielding layer, the intrusion of electromagnetic interference such as EMP can be effectively blocked, thereby protecting the signal transmitted by the fiber optic from being affected.

[0006] The objective of this invention and the technical problem it solves are achieved through the following technical solution. This invention proposes a method for fabricating an electromagnetic pulse-resistant fiber optic imaging element, comprising the following steps:

[0007] S1 is formed by matching the core glass rod and the outer glass tube and drawing them into a single filament;

[0008] S2 draws metal materials as metal rods into metal wires;

[0009] S3 arranges the single wires obtained in step S1 into a hexagonal densest arrangement, and arranges the metal wires obtained in step S2 into wires according to the rules of intermittent insertion, replacement insertion, or a combination of intermittent and replacement insertion to obtain a primary composite rod, and then draws the primary composite rod into a primary multifilament with a regular hexagonal cross-section.

[0010] S4 arranges the primary multifilaments obtained in step S3 into a secondary composite rod with a regular hexagonal cross-section, and draws the secondary composite rod into a secondary multifilament;

[0011] S5 arranges the secondary multifilaments obtained in step S4 into a hexagonal close-packed arrangement, cuts them to a fixed length, and arranges them into plate segments.

[0012] S6 The plate segment obtained in step S5 is hot-melted and pressed to obtain the electromagnetic pulse resistant fiber optic imaging element.

[0013] The objectives of this invention and the technical problems solved can be further achieved by the following technical measures.

[0014] Preferably, in the aforementioned method for preparing an electromagnetic pulse-resistant fiber optic imaging element, in step S3, the gap insertion is performed by inserting the metal wire obtained in step S2 into all the gaps between the single wires.

[0015] Preferably, in the aforementioned method for preparing an electromagnetic pulse-resistant fiber optic imaging element, in step S3, the replacement insertion is as follows: light-absorbing filaments are inserted alternately into the gaps between primary filaments, structural filaments with the same composition as the glass material are inserted into the remaining gaps, and metal filaments replace the primary filaments located at the center.

[0016] Preferably, in the aforementioned method for preparing an electromagnetic pulse-resistant fiber optic imaging element, in step S3, the gap-type and replacement-type combined insertion is: inserting a metal wire into all the gaps between primary monofilaments, while simultaneously replacing the primary monofilament located at the center position with a metal wire.

[0017] Preferably, in the aforementioned method for preparing an electromagnetic pulse-resistant fiber optic imaging element, step S6 further includes stretching: the optical fiber plate blank obtained by hot melt pressing is processed and stretched to obtain an optical cone.

[0018] Preferably, in the aforementioned method for preparing an electromagnetic pulse-resistant fiber optic imaging element, in step S6, the unit filament diameter of the fiber optic panel or optical fiber board blank is 3.85-4.05 μm.

[0019] The objective of this invention and the technical problem it solves are achieved by the following technical solution. This invention proposes an electromagnetic pulse-resistant fiber optic imaging element, comprising an output end, an input end, and an optical fiber portion disposed between the output end and the input end; the optical fiber portion comprises a plurality of optical fibers, each with a unit filament diameter of 3.85-4.05 μm.

[0020] The objectives of this invention and the technical problems solved can be further achieved by the following technical measures.

[0021] Preferably, the aforementioned electromagnetic pulse-resistant fiber optic imaging element is a fiber optic panel or a fiber optic taper.

[0022] The objectives of this invention and the solutions to its technical problems can also be achieved using the following technical measures. This invention proposes a high-energy ray imaging device, which includes an electromagnetic pulse-resistant fiber optic imaging element; the electromagnetic pulse-resistant fiber optic imaging element includes an output end, an input end, and an optical fiber portion disposed between the output end and the input end; the optical fiber portion includes a plurality of optical fibers, the unit diameter of which is 3.85-4.05 μm.

[0023] The objectives of this invention and the solutions to its technical problems can also be achieved using the following technical measures. This invention proposes a night vision device, which includes an electromagnetic pulse-resistant fiber optic image transmission element; the electromagnetic pulse-resistant fiber optic image transmission element includes an output end, an input end, and an optical fiber portion disposed between the output end and the input end; the optical fiber portion includes a plurality of optical fibers, the unit filament diameter of which is 3.85-4.05 μm.

[0024] Compared with existing technologies, the electromagnetic pulse-resistant fiber optic imaging element, its fabrication method, and its application described in this invention have the following advantages:

[0025] This invention creates an electromagnetic shielding layer by adding a metal wire to the optical fiber imaging element. This effectively blocks the intrusion of electromagnetic interference such as EMP, improves the anti-interference performance of the power system, and ensures normal operation in complex electromagnetic environments. It maintains effective optical signal transmission and also provides an electromagnetic pulse protection barrier for the image sensor, preventing image noise or signal loss caused by electromagnetic interference.

[0026] This invention enhances the anti-electromagnetic pulse capability through a single-filament arrangement structure design. This design, by inserting conductive metal wires into the optical fiber array, can effectively shield electromagnetic wave interference while maintaining the high light transmittance of the optical fiber, ensuring the integrity of the optical signal during transmission.

[0027] The core of this invention lies in the rational optimization of the structure and manufacturing process to achieve excellent electromagnetic shielding effect without affecting optical performance. It not only has broad prospects in military applications, but also expands the application potential of fiber optic imaging elements in high-risk electromagnetic environments.

[0028] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of a single-wire multifilament of the present invention (interval insertion of metal wires);

[0030] Figure 2 This is a schematic diagram of the structure of a single-wire multifilament of the present invention (metal wire replacement insertion);

[0031] Figure 3 This is a schematic diagram of the structure of the primary multifilament of the present invention (a combination of gap-type and replacement-type insertion of metal wires);

[0032] Figure 4 This is a schematic diagram of a single-filament structure in the prior art;

[0033] Figure 5 This is a schematic diagram of the fiber optic section of the electromagnetic pulse-resistant fiber optic imaging element of the present invention. Wherein, 1a - single fiber filament; 1b - single fiber filament; 1c - single fiber filament; 1d - single fiber filament; 1e - fiber core layer;

[0034] 2a-Metal wire; 2b-Light absorbing wire; 2c-Metal wire; 2d-Light absorbing wire; 2e-Light absorbing wire;

[0035] 3b - Structural wire; 3c - Metal wire; 3d - Structural wire; 3e - Structural wire;

[0036] 4b - Metal wire; 4e - Fiber optic sheath. Detailed Implementation

[0037] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the following detailed description, in conjunction with preferred embodiments, provides a detailed explanation of the specific implementation, structure, features, and effects of an electromagnetic pulse-resistant fiber optic imaging element, its fabrication method, and its application according to the present invention. In the following description, different "embodiments" or "embodiments" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable manner.

[0038] Unless otherwise specified, all materials and reagents mentioned below are commercially available products well-known to those skilled in the art; unless otherwise specified, all methods described are methods known in the art. Unless otherwise defined, the technical or scientific terms used should have the ordinary meaning understood by those skilled in the art. Where specific experimental steps or conditions are not specified below, they can be performed according to the conventional experimental steps or conditions described in the literature in this field.

[0039] Some embodiments of the present invention provide a method for fabricating an electromagnetic pulse-resistant fiber optic imaging element, comprising the following steps:

[0040] S1 involves matching a core glass rod with a refractive index between 1.86 and 1.88 (wavelengths of 580nm-656nm) and a sheath glass tube with a refractive index between 1.45 and 1.48 (wavelengths of 580nm-656nm). The resulting fiber is then drawn into a single filament at 810℃ to 850℃ for 30-120 minutes. Below 810℃, the fiber filament cannot be drawn at a uniform speed, and breakage may occur, damaging its mechanical and optical properties. Above 850℃, the drawing speed is also difficult to control, resulting in a faster and less uniform fiber filament, which further affects its optical performance. The diameter of the optical fiber filaments ranges from 2.5mm to 2.7mm to maintain sufficient strength and stability. A filament diameter smaller than 2.5mm increases the number of filaments required for arrangement, while a diameter larger than 2.7mm reduces the number of filaments required for arrangement, making it difficult to form a regular hexagonal arrangement. Light-absorbing glass rods are drawn into light-absorbing filaments with a diameter of 0.34-0.36mm at 820℃-860℃ for 35-120 minutes.

[0041] S2 uses either nickel-chromium alloy or 7075 aluminum alloy as the metal rod. Nickel-chromium alloy has excellent electromagnetic shielding properties, effectively resisting electromagnetic pulse interference. Nickel-chromium alloy maintains good bonding with silicate glass at high temperatures, effectively reducing thermal stress. 7075 aluminum alloy has good electrical conductivity and electromagnetic shielding properties. Aluminum alloy has good mechanical properties and corrosion resistance, making it suitable for simultaneous melting and molding with glass. The metal rod is drawn at 750-855℃ for 40-115 minutes to form a wire with a diameter of 0.33-0.35mm or 2.5-2.7mm. When the temperature is below 750℃, it is difficult to draw to the desired wire diameter, affecting the contact between the metal wire and the optical fiber. When the temperature is above 855℃, the drawing speed of the metal wire becomes uncontrollable, making it difficult to achieve a uniform drawing speed and ultimately failing to reach the desired wire diameter. When the diameter of the metal wire is less than 0.33mm or 2.5mm, the number of wires required for arrangement will increase. Similarly, when the diameter of the metal wire is greater than 0.35mm or 22.7mm, the number of wires required for arrangement will decrease, making it difficult to form a regular hexagonal arrangement.

[0042] S3 arranges the single filaments obtained in step S1 into a hexagonal close-packed arrangement. The metal wires obtained in step S2 are then arranged according to a pattern of intermittent insertion, substitution insertion, or a combination of intermittent and substitution insertion. These are then bound with cotton thread, and both ends are bound with non-flammable copper wire. The fiber is then clamped in a drawing machine and drawn at 780℃-840℃ for 30-130 minutes. If the temperature is below 780℃, the fiber filaments cannot be drawn at a uniform speed, which also damages their mechanical and optical properties. If the temperature is above 840℃, the drawing speed is difficult to control, resulting in a faster drawing speed and uneven thickness along the length of the fiber filaments, affecting their optical performance. The final product is a primary multifilament with a regular hexagonal cross-section and opposite side dimensions of 1.02mm-1.03mm. When the opposite side dimension of the primary multifilament is less than 1.02mm, the number of primary multifilaments to be laid out will increase. Similarly, when the diameter of the primary multifilament is greater than 1.03mm, the number of primary multifilaments to be laid out will decrease, making it difficult to form a regular hexagonal arrangement.

[0043] In step S3, the gap insertion involves inserting the metal wires 2a obtained in step S2 into all the gaps between the fiber optic monofilaments 1a, such as... Figure 1 As shown, this arrangement not only shields EMP but also absorbs stray light. The replacement insertion involves inserting the light-absorbing wires 2b into the gaps between the fiber filaments 1b at alternating rows, inserting structural wires 3b with the same material composition as the glass skin into the remaining gaps, and replacing the central fiber filament 1b with metal wires 4b. Figure 2 As shown, unlike the previous method of inserting metal wires, this insertion method can still achieve EMP shielding while also maintaining the light transmission performance of the fiber optic imaging element; the gap-type and replacement-type combined insertion is as follows: metal wire 2c is inserted into all the gaps between fiber optic monofilaments 1c, while metal wire 3c replaces the fiber optic monofilament 1c located in the center position, as shown. Figure 3 As shown, this wire insertion method combines the above two insertion methods, taking into account stronger EMP resistance. The area ratio of the wires in the primary composite rod under the three wire insertion methods is calculated, as shown in Table 1. While considering the wire insertion's resistance to EMP, the light transmission performance of the fiber optic imaging element must also be taken into account. The impact on the light transmittance of the fiber optic imaging element can be judged by calculating the area ratio of the wires, as shown in Table 1. In the existing technology, multiple fiber monofilaments 1d are arranged in a hexagonal close-packed arrangement, and light-absorbing wires 2d are inserted into the gaps formed by the hexagonal close-packed arrangement of multiple fiber monofilaments 1d according to a certain pattern. Simultaneously, structural wires 3d with the same composition as the glass liner are inserted into the remaining gaps, forming... Figure 4 The initial single-filament structure shown is similar to... Figures 1-3 Their structures are different.

[0044] Table 1

[0045] Area percentage occupied by metal wire (%) Intermittent insertion 2.96 Replacement Insertion 1.49 Interval and replacement combination insertion 4.45

[0046] S4 arranges the primary multifilament obtained in step S3 into a hexagonal close-packed arrangement and binds it with cotton thread. Both ends are bound with non-flammable copper wire. It is then clamped in a drawing machine and drawn at 790℃-845℃ for 50-200 minutes. When the temperature is below 790℃, the fiber filament cannot be stretched at a uniform speed, damaging its mechanical and optical properties. When the temperature is above 845℃, the drawing speed is difficult to control, resulting in a faster drawing speed and uneven thickness along the length of the fiber filament, affecting its optical performance. The final result is a secondary multifilament with a regular hexagonal cross-section and opposite sides of 0.81mm-0.83mm. If the opposite sides of the secondary multifilament are less than 0.81mm, the number of fibers required for arrangement increases; similarly, if the diameter of the secondary multifilament is greater than 0.83mm, the number of fibers required for arrangement decreases, making it difficult to form a regular hexagonal arrangement.

[0047] In step S5, the secondary multifilaments obtained in step S4 are arranged in a hexagonal close-packed configuration and then bound tightly with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into fiber blanks of 90-140mm in length. If the length of the cut composite fiber bundle is shorter or longer than 90-140mm, it will not conform to the dimensions of the melting and pressing mold, thus affecting the melting and pressing process. The fiber blank has a regular hexagonal cross-section with opposite sides of 20-45mm.

[0048] S6 places the plate segment obtained in step S5 into a thermoforming mold. The mold containing the plate segment is then placed into a thermoforming furnace at a high temperature of 530℃-560℃. When the temperature is below 530℃, the optical fibers are not tightly bonded, affecting light transmission. When the temperature is above 560℃, deformation occurs between the optical fibers, resulting in optical loss. Pressure of 60N-80N is applied to the six directions of the optical fiber blank to begin pressing. When the pressure is less than 60N, insufficient contact between the individual filaments within the composite fiber bundle prevents tight bonding, leading to gaps or interface defects in the fiber array. The fiber array may struggle to maintain a stable shape and is susceptible to deformation under mechanical stress or temperature changes during subsequent use, ultimately severely impacting the fiber's transmission performance. At high temperatures, when the pressure exceeds 80N, excessive pressure may cause some fibers to flow, disrupting the array's regular arrangement and causing irregular deformation, ultimately affecting the fiber's optical performance. The pressing time for hot-melt molding is controlled between 160 and 180 minutes. If the time is less than 160 minutes, insufficient hot-melt molding time will result in the monofilaments not reaching a sufficiently softened state, failing to form a regular array structure, and the optical performance may be affected by local defects, exhibiting inconsistencies. If the time is greater than 180 minutes, prolonged heating will cause stress concentration areas to form in the fiber blank, increasing the risk of microcracks or thermal damage. It will also cause deformation of the monofilament cross-section, thereby increasing optical transmission loss. The final product is a fiber optic panel or optical fiber board blank with a unit filament diameter of 3.85-4.05 μm.

[0049] In the above technical solution, this invention proposes an optical fiber structure design that incorporates conductive metal wires into the optical fiber image bundle. This design, by fusing metal materials into the optical fiber array, forms effective electromagnetic shielding, reducing interference from external electromagnetic waves on the optical signal. Simultaneously, it maintains the high transmittance of the optical fiber, ensuring the signal integrity remains intact during transmission.

[0050] Introducing metallic materials into fiber optic image transmission bundles is considered, as metal wires possess excellent conductivity and electromagnetic shielding properties. Adding metal wires to fiber optic image transmission elements can form an electromagnetic shielding layer, effectively blocking the intrusion of electromagnetic interference such as EMP, thereby protecting the transmitted signal from interference. This invention enhances its electromagnetic pulse resistance through a single-wire arrangement structure design. This design, by inserting conductive metal wires into the fiber array, effectively shields against electromagnetic wave interference while maintaining the high transmittance of the fiber, ensuring the integrity of the optical signal during transmission. The core of this invention lies in the rational optimization of the structure and fabrication process to achieve superior electromagnetic shielding without compromising optical performance. Such technological innovation not only has broad prospects in military applications but also expands the application potential of fiber optic image transmission elements in high-risk electromagnetic environments.

[0051] In some optional embodiments, step S6 further includes stretching: stretching the obtained 3.85-4.05μm optical fiber board blank at a temperature of 720℃-750℃ to obtain a highly uniform optical cone with a length of 70-80mm, a large end diameter of 25-30mm, and a small end diameter of 8-15mm.

[0052] Some embodiments of the present invention provide an electromagnetic pulse-resistant fiber optic imaging element, comprising an output end, an input end, and an optical fiber portion disposed between the output end and the input end; the optical fiber portion comprises a plurality of optical fibers, wherein the optical fibers, from the inside out, are an optical fiber core layer 1e and an optical fiber sheath 4e, and light-absorbing wires 2e and structural wires 3e are inserted between the plurality of optical fibers, see Figure 5 Tests showed that the shielding effectiveness of the electromagnetic pulse-resistant fiber optic imaging element was 48-95 dB.

[0053] In some alternative embodiments, the fiber optic imaging element may be a fiber optic panel or a fiber optic taper.

[0054] Some embodiments of the present invention also provide a high-energy ray imaging device, which includes the above-described electromagnetic pulse-resistant fiber optic imaging element.

[0055] Some embodiments of the present invention also provide a night vision device comprising the aforementioned electromagnetic pulse resistant fiber optic imaging element.

[0056] The present invention will be further described below with reference to specific embodiments, but this should not be construed as a limitation on the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above description of the present invention still fall within the scope of protection of the present invention.

[0057] Example 1: EMP-resistant fiber optic panel (metal wire material: nickel-chromium alloy) - gap insertion fabrication method is as follows:

[0058] (1) After matching the core glass rod with a refractive index of 1.87 at a wavelength of 594nm and the skin glass tube with a refractive index of 1.47 at a wavelength of 594nm, the single wire is drawn at 820℃ for 45 minutes to obtain a drawn 2.6μm single wire. Since nickel-chromium alloy has good high temperature resistance and strength, it can remain stable in environments up to 1000℃ and has excellent electromagnetic shielding performance, effectively resisting electromagnetic pulse interference. Nickel-chromium alloy material can be drawn into a 0.35μm metal wire at 840℃ for 60 minutes.

[0059] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 1 The optical fiber arrangement is illustrated in the diagram. Metal wires are inserted into the gaps between the individual fiber filaments. The fibers are then bound with cotton thread, and both ends are bound with non-flammable copper wire. The fiber is then clamped in a drawing machine and drawn at 830°C for 50 minutes to form a single-sided multifilament with a side dimension of 1.02 μm and a regular hexagonal cross-section.

[0060] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, and then tied with cotton thread. Both ends are tied with non-flammable copper wire. Then, it is clamped on a drawing machine and drawn at a temperature of 830°C for 65 minutes to form a secondary multifilament with a side dimension of 0.82μm and a cross-section of regular hexagon.

[0061] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0062] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 70N is applied to the six directions of the fiber blank to start pressing. The time is controlled at 170 minutes to obtain an optical fiber panel with a unit wire diameter of 3.9μm.

[0063] Example 2: EMP-resistant fiber optic panel (metal wire material: nickel-chromium alloy) - Replacement insertion preparation method is as follows:

[0064] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and drawn into a single wire at 820°C for 45 minutes to obtain a 2.6 μm single wire. Due to the good high temperature resistance and strength of nickel-chromium alloy, it can remain stable in environments up to 1000°C and has excellent electromagnetic shielding performance, effectively resisting electromagnetic pulse interference. Nickel-chromium alloy material can be selected to be drawn into a 2.6 μm metal wire at 820°C for 50 minutes. A light-absorbing glass rod was drawn into a 0.35 μm light-absorbing wire at 825°C for 50 minutes. A sheath glass with a refractive index of 1.47 at a wavelength of 594 nm was drawn into a structural wire at 830°C for 55 minutes to obtain a 0.35 μm structural wire.

[0065] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 2 The optical fiber arrangement is illustrated in the diagram. The optical fiber is arranged by inserting light-absorbing wires and structural wires in the gaps between the optical fiber monofilaments in alternating rows. The optical fiber monofilament in the center is replaced with a metal wire and then tied with cotton thread. The two ends are tied with non-flammable copper wire. Then, it is clamped on a wire drawing machine and drawn at 830°C for 50 minutes to form a primary multifilament with a side dimension of 1.02μm and a cross-section of regular hexagon.

[0066] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, and then tied with cotton thread. Both ends are tied with non-flammable copper wire. Then, it is clamped on a drawing machine and drawn at a temperature of 830°C for 65 minutes to form a primary multifilament with a side dimension of 0.82μm and a cross-section of regular hexagon.

[0067] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0068] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 70N is applied to the six directions of the fiber blank to start pressing. The time is controlled at 170 minutes to obtain an optical fiber panel with a unit wire diameter of 3.9μm.

[0069] Example 3: EMP-resistant fiber optic panel (metal wire material: nickel-chromium alloy) - gap-type and replacement-type combination insertion

[0070] The preparation method is as follows:

[0071] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a skin glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and drawn into a single wire at 820℃ for 45 minutes to obtain a 2.6 μm single wire. Since nickel-chromium alloy has good high temperature resistance and strength, it can remain stable in environments up to 1000℃ and has excellent electromagnetic shielding performance, effectively resisting electromagnetic pulse interference. Nickel-chromium alloy material can be drawn into a 2.6 μm metal wire at 820℃ for 50 minutes. At the same time, nickel-chromium alloy material is drawn into a 0.35 μm metal wire at 840℃ for 60 minutes.

[0072] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 3 The fiber arrangement diagram shows the fiber arrangement structure, in which metal wires are inserted into all the gaps between the fiber monofilaments, and the fiber monofilament in the center is replaced with a metal wire and inserted, and then tied with cotton thread, and the two ends are tied with non-flammable copper wire, and then clamped on the wire drawing machine and drawn at 830°C for 50 minutes to form a primary multifilament with a side dimension of 1.02μm and a cross-section of regular hexagon.

[0073] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, and then tied with cotton thread. Both ends are tied with non-flammable copper wire. Then, it is clamped on a drawing machine and drawn at a temperature of 830°C for 65 minutes to form a primary multifilament with a side dimension of 0.82μm and a cross-section of regular hexagon.

[0074] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0075] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 70N is applied to the six directions of the fiber blank to start pressing. The time is controlled at 170 minutes to obtain an optical fiber panel with a unit wire diameter of 3.9μm.

[0076] Comparative Example 1: Fiber Optic Panel

[0077] The preparation method is as follows:

[0078] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and then drawn into a single filament at 820°C for 45 minutes to obtain a 2.6 μm single filament. A light-absorbing glass rod was drawn into a 0.35 μm light-absorbing filament at 825°C for 50 minutes. A sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm was drawn into a structural filament at 830°C for 55 minutes to obtain a 0.35 μm structural filament.

[0079] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 4 The optical fiber arrangement diagram shows the structure of the fiber arrangement, in which light absorption wires and structural wires are inserted in the gaps between the single fiber filaments in sequence, and then tied with cotton thread. The two ends are tied with non-flammable copper wire, and then clamped on the fiber drawing machine and drawn at 815°C for 50 minutes to form a primary multifilament with a side dimension of 1.02μm and a regular hexagonal cross section.

[0080] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, and then tied with cotton thread. Both ends are tied with non-flammable copper wire. Then, it is clamped on a drawing machine and drawn at a temperature of 835°C for 65 minutes to form a primary multifilament with a side dimension of 0.82μm and a cross-section of regular hexagon.

[0081] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0082] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 70N is applied to the six directions of the fiber blank to start pressing. The time is controlled at 170 minutes to obtain an optical fiber panel with a unit wire diameter of 3.9μm.

[0083] The shielding effectiveness (SE) and light transmittance (collimated light) results obtained from the electromagnetic pulse resistance tests of the fiber optic panels obtained in Examples 1-3 and Comparative Example 1 are summarized in Table 2.

[0084] Table 2

[0085]

[0086] According to the shielding effectiveness data in Table 2, the shielding effectiveness is greatly improved by inserting nickel-chromium alloy wires into the optical fiber compared to the traditional optical fiber panel. The effect of using replacement-type insertion of metal wires is better than that of gap-type insertion of metal wires, and the combined insertion of the two is the best. However, at the same time, the nickel-chromium alloy metal wires occupy more effective area in the optical fiber, which seriously reduces the optical performance of the optical fiber panel and results in the worst light transmission efficiency.

[0087] Example 4: EMP-resistant fiber optic panel (metal wire material: 7075 aluminum alloy) - gap insertion

[0088] The preparation method is as follows:

[0089] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and drawn into a single filament at 820℃ for 45 minutes to obtain a 2.6 μm single filament. 7075 aluminum alloy has good electrical conductivity, which can effectively reflect and disperse electromagnetic waves, thus providing a certain electromagnetic shielding performance. During high-temperature drawing, its mechanical properties support the structural requirements of optical fibers, reducing the risk of deformation and strength reduction. 7075 aluminum alloy material can be drawn into a 0.35 μm metal wire at 770℃ for 80 minutes.

[0090] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 1 The optical fiber arrangement is illustrated in the diagram. Metal wires are inserted into the gaps between the individual fiber filaments. The fibers are then bound with cotton thread, and both ends are bound with non-flammable copper wire. The fiber is then clamped in a drawing machine and drawn at 790°C for 55 minutes to form a single-sided multifilament with a side dimension of 1.02 μm and a regular hexagonal cross-section.

[0091] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, tied with cotton thread, and tied with non-flammable copper wire at both ends. Then, it is clamped on a drawing machine and drawn at 800°C for 70 minutes to form a primary multifilament with a side dimension of 0.82μm and a regular hexagonal cross section.

[0092] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0093] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 65N is applied to the six directions of the fiber blank to start pressing. The pressing time of hot melt pressing is controlled at 165 minutes, so that a fiber panel with a unit wire diameter of 3.9μm is obtained.

[0094] Example 5: EMP-resistant fiber optic panel (metal wire material: 7075 aluminum alloy) - Replacement insert

[0095] The preparation method is as follows:

[0096] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and drawn into a single filament at 820°C for 45 minutes to obtain a drawn 2.6 μm single filament. 7075 aluminum alloy has good electrical conductivity and can effectively reflect and disperse electromagnetic waves, thereby providing a certain electromagnetic shielding performance. During high-temperature drawing, its mechanical properties support the structural requirements of optical fiber and can reduce the risk of deformation and strength reduction. 7075 aluminum alloy material can be selected to be drawn into a 2.6 μm metal wire at 760°C for 45 minutes. The light-absorbing glass rod was drawn into a 0.35 μm light-absorbing filament at 825°C for 50 minutes. The sheath glass with a refractive index of 1.47 at a wavelength of 594 nm was drawn into a structural filament at 830°C for 55 minutes to obtain a drawn 0.35 μm structural filament.

[0097] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 2 The optical fiber arrangement is illustrated in the diagram. The optical fiber is arranged by inserting light-absorbing wires and structural wires in the gaps between the optical fiber monofilaments in alternating rows. The optical fiber monofilament in the center is replaced with a metal wire and then tied with cotton thread. The two ends are tied with non-flammable copper wire. Then, it is clamped on a wire drawing machine and drawn at 790°C for 55 minutes to form a primary multifilament with a side dimension of 1.02μm and a cross-section of regular hexagon.

[0098] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, and then tied with cotton thread. Both ends are tied with non-flammable copper wire. Then, it is clamped on a drawing machine and drawn at 700°C for 70 minutes to form a primary multifilament with a side dimension of 0.82μm and a regular hexagonal cross section.

[0099] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0100] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 65N is applied to the six directions of the fiber blank to start pressing. The time is controlled at 165 minutes to obtain a fiber panel with a unit wire diameter of 3.9μm.

[0101] Example 6: EMP-resistant fiber optic panel (metal wire material: 7075 aluminum alloy) - gap-type and replacement-type combination insertion

[0102] The preparation method is as follows:

[0103] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and drawn into a single filament at 820℃ for 45 minutes to obtain a 2.6 μm single filament. 7075 aluminum alloy has good electrical conductivity and can effectively reflect and disperse electromagnetic waves, thereby providing a certain electromagnetic shielding performance. During high-temperature drawing, its mechanical properties support the structural requirements of optical fiber and can reduce the risk of deformation and strength reduction. 7075 aluminum alloy material can be drawn into a 2.6 μm metal wire at 760℃ for 45 minutes. At the same time, 7075 aluminum alloy material can be drawn into a 0.35 μm metal wire at 770℃ for 80 minutes.

[0104] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 3 The fiber arrangement diagram shows the fiber arrangement structure, in which metal wires are inserted into all the gaps between the fiber monofilaments, and the fiber monofilament in the center is replaced with a metal wire and inserted, and then tied with cotton thread, and the two ends are tied with non-flammable copper wire, and then clamped on the wire drawing machine and drawn at 790°C for 55 minutes to form a primary multifilament with a side dimension of 1.02μm and a cross-section of regular hexagon.

[0105] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, tied with cotton thread, and tied with non-flammable copper wire at both ends. Then, it is clamped on a drawing machine and drawn at 800°C for 70 minutes to form a primary multifilament with a side dimension of 0.82μm and a regular hexagonal cross section.

[0106] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0107] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 65N is applied to the six directions of the fiber blank to start pressing. The pressing time of hot melt pressing is controlled at 165 minutes, so that a fiber panel with a unit wire diameter of 3.9μm is obtained.

[0108] The shielding effectiveness (SE) and light transmittance (collimated light) results obtained from the electromagnetic pulse resistance tests of the fiber optic panels obtained in Examples 4-6 and Comparative Example 1 are summarized in Table 3.

[0109] Table 3

[0110]

[0111] According to the shielding effectiveness data in Table 3, inserting 7075 aluminum alloy wires into the optical fiber significantly improves the shielding effectiveness compared to traditional optical fiber panels (Comparative Example 1). The effect of using replacement insertion (Example 5) of the wires is better than that of gap insertion (Example 4), while the combined insertion of both (Example 6) is the best. However, regardless of the method, the overall shielding effectiveness is lower than that of nickel-chromium alloy wires. The increased area occupied by 7075 aluminum alloy wires in the optical fiber severely reduces optical performance, resulting in the worst light transmission efficiency. Compared to optical fiber panels with nickel-chromium alloy wires, there is no significant difference in transmittance.

[0112] Example 7: EMP-resistant fiber optic taper (metal wire material: nickel-chromium alloy) - gap insertion fabrication method is as follows:

[0113] (1) After matching the core glass rod with a refractive index of 1.87 at a wavelength of 594nm and the skin glass tube with a refractive index of 1.47 at a wavelength of 594nm, the single wire is drawn at a temperature of 820℃ for 45 minutes to obtain a drawn 2.6μm single wire. Since nickel-chromium alloy has good high temperature resistance and strength, it can remain stable in an environment up to 1000℃ and has excellent electromagnetic shielding performance, which can effectively resist electromagnetic pulse interference. Nickel-chromium alloy material can be drawn into a 0.35μm metal wire at 840℃ for 60 minutes.

[0114] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 1The optical fiber arrangement is illustrated in the diagram. Metal wires are inserted into the gaps between the individual fiber filaments. The fibers are then bound with cotton thread, and both ends are bound with non-flammable copper wire. The fiber is then clamped in a drawing machine and drawn at 830°C for 50 minutes to form a single-sided multifilament with a side dimension of 1.02 μm and a regular hexagonal cross-section.

[0115] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, and then tied with cotton thread. Both ends are tied with non-flammable copper wire. Then, it is clamped on a drawing machine and drawn at a temperature of 830°C for 65 minutes to form a primary multifilament with a side dimension of 0.82μm and a cross-section of regular hexagon.

[0116] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0117] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 70N is applied to the six directions of the fiber blank to start pressing. The pressing time of hot melt pressing is controlled at 170 minutes, so that a fiber blank with a unit wire diameter of 3.9μm is obtained.

[0118] (6) Stretching: The blank is stretched at a temperature of 730°C to obtain a highly uniform light cone with a length of 75 mm, a large end diameter of 27 mm, and a small end diameter of 9 mm.

[0119] Example 8: EMP-resistant fiber optic taper (metal wire material: nickel-chromium alloy) - Replacement insertion preparation method is as follows:

[0120] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and drawn into a single wire at 820°C for 45 minutes to obtain a 2.6 μm single wire. Due to the good high temperature resistance and strength of nickel-chromium alloy, it can remain stable in environments up to 1000°C and has excellent electromagnetic shielding performance, which can effectively resist electromagnetic pulse interference. Nickel-chromium alloy material can be selected to be drawn into a 2.6 μm metal wire at 820°C for 50 minutes. A light-absorbing glass rod was drawn into a 0.35 μm light-absorbing wire at 825°C for 50 minutes. A sheath glass with a refractive index of 1.47 at a wavelength of 594 nm was drawn into a structural wire at 830°C for 55 minutes to obtain a 0.35 μm structural wire.

[0121] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 2 The optical fiber arrangement is illustrated in the diagram. The optical fiber is arranged by inserting light-absorbing wires and structural wires in the gaps between the optical fiber monofilaments in alternating rows. The optical fiber monofilament in the center is replaced with a metal wire and then tied with cotton thread. The two ends are tied with non-flammable copper wire. Then, it is clamped on a wire drawing machine and drawn at 830°C for 50 minutes to form a primary multifilament with a side dimension of 1.02μm and a cross-section of regular hexagon.

[0122] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, and then tied with cotton thread. Both ends are tied with non-flammable copper wire. Then, it is clamped on a drawing machine and drawn at a temperature of 830°C for 65 minutes to form a primary multifilament with a side dimension of 0.82μm and a cross-section of regular hexagon.

[0123] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0124] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 70N is applied to the six directions of the fiber blank to start pressing. The pressing time of hot melt pressing is controlled at 170 minutes, so that a fiber blank with a unit wire diameter of 3.9μm is obtained.

[0125] (6) Stretching: The blank is stretched at 730°C to obtain a highly uniform light cone with a length of 75mm, a large end diameter of 27mm, and a small end diameter of 9mm.

[0126] Example 9: EMP-resistant fiber optic taper (metal wire material: nickel-chromium alloy) - gap-type and replacement-type combined insertion

[0127] The preparation method is as follows:

[0128] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a skin glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and drawn into a single wire at 820°C for 45 minutes to obtain a 2.6 μm single wire. Since nickel-chromium alloy has good high temperature resistance and strength, it can remain stable in environments up to 1000°C and has excellent electromagnetic shielding performance, which can effectively resist electromagnetic pulse interference. Nickel-chromium alloy material can be drawn into a 2.6 μm metal wire at 820°C for 50 minutes. At the same time, nickel-chromium alloy material is drawn into a 0.35 μm metal wire at 840°C for 60 minutes.

[0129] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 3 The fiber arrangement diagram shows the fiber arrangement structure, in which metal wires are inserted into all the gaps between the fiber monofilaments, and the fiber monofilament in the center is replaced with a metal wire and inserted, and then tied with cotton thread, and the two ends are tied with non-flammable copper wire, and then clamped on the wire drawing machine and drawn at 830°C for 50 minutes to form a primary multifilament with a side dimension of 1.02μm and a cross-section of regular hexagon.

[0130] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, and then tied with cotton thread. Both ends are tied with non-flammable copper wire. Then, it is clamped on a drawing machine and drawn at a temperature of 830°C for 65 minutes to form a primary multifilament with a side dimension of 0.82μm and a cross-section of regular hexagon.

[0131] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0132] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 70N is applied to the six directions of the fiber blank to start pressing. The time is controlled at 170 minutes to obtain a fiber blank with a unit wire diameter of 3.9μm.

[0133] (6) Stretching: The blank is stretched at 730°C to obtain a highly uniform light cone with a length of 75mm, a large end diameter of 27mm, and a small end diameter of 9mm.

[0134] Comparative Example 2: Fiber Optic Cone

[0135] The preparation method is as follows:

[0136] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and then drawn into a single filament at 820°C for 45 minutes to obtain a 2.6 μm single filament. A light-absorbing glass rod was drawn into a 0.35 μm light-absorbing filament at 825°C for 50 minutes. A sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm was drawn into a structural filament at 830°C for 55 minutes to obtain a 0.35 μm structural filament.

[0137] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 2 The optical fiber arrangement diagram shows the structure of the fiber arrangement, in which light absorption wires and structural wires are inserted in the gaps between the single fiber filaments in sequence, and then tied with cotton thread. The two ends are tied with non-flammable copper wire, and then clamped on the fiber drawing machine and drawn at 815°C for 50 minutes to form a primary multifilament with a side dimension of 1.02μm and a regular hexagonal cross section.

[0138] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, and then tied with cotton thread. Both ends are tied with non-flammable copper wire. Then, it is clamped on a drawing machine and drawn at a temperature of 835°C for 65 minutes to form a primary multifilament with a side dimension of 0.82μm and a cross-section of regular hexagon.

[0139] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0140] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 70N is applied to the six directions of the fiber blank to start pressing. The time is controlled at 170 minutes to obtain a fiber blank with a unit wire diameter of 3.9μm.

[0141] (6) Stretching: The blank is stretched at a temperature of 730°C to obtain a highly uniform light cone with a length of 75 mm, a large end diameter of 27 mm, and a small end diameter of 9 mm.

[0142] The shielding effectiveness (SE) and light transmittance (collimated light) results obtained from the electromagnetic pulse resistance tests of the fiber optic panels obtained in Examples 7-9 and Comparative Example 2 are summarized in Table 3.

[0143] Table 4

[0144]

[0145] According to the shielding effectiveness data in Table 4, inserting nickel-chromium alloy wires into the optical fiber significantly improves the shielding effectiveness compared to traditional fiber tapers (Comparative Example 2). Similarly, the effect of using replacement-type insertion (Example 8) of the wires is better than that of gap-type insertion (Example 7), while the combined insertion of both (Example 9) yields the best effect. Compared to an optical fiber panel with the same wire material, the electromagnetic shielding performance of the fiber taper is slightly worse. Because the nickel-chromium alloy wires occupy an increased effective area within the optical fiber, the optical performance of the fiber taper is severely reduced, resulting in the worst light transmission efficiency. Furthermore, due to the relatively complex transmission path of the light within the tapered fiber inside the fiber taper, light transmission loss is higher, and the transmittance is worse than that of an optical fiber panel.

[0146] Example 10: EMP-resistant fiber optic taper (metal wire material: 7075 aluminum alloy) - gap insertion

[0147] The preparation method is as follows:

[0148] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and drawn into a single filament at 820℃ for 45 minutes to obtain a 2.6 μm single filament. 7075 aluminum alloy has good electrical conductivity and can effectively reflect and disperse electromagnetic waves, thereby providing a certain electromagnetic shielding performance. During high-temperature drawing, its mechanical properties support the structural requirements of optical fiber and can reduce the risk of deformation and strength reduction. 7075 aluminum alloy material can be drawn into a 0.35 μm metal wire at 770℃ for 80 minutes.

[0149] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 1 The optical fiber arrangement is illustrated in the diagram. Metal wires are inserted into the gaps between the individual fiber filaments. The fibers are then bound with cotton thread, and both ends are bound with non-flammable copper wire. The fiber is then clamped in a drawing machine and drawn at 790°C for 55 minutes to form a single-sided multifilament with a side dimension of 1.02 μm and a regular hexagonal cross-section.

[0150] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, tied with cotton thread, and tied with non-flammable copper wire at both ends. Then, it is clamped on a drawing machine and drawn at 800°C for 70 minutes to form a primary multifilament with a side dimension of 0.82μm and a regular hexagonal cross section.

[0151] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0152] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 65N is applied to the six directions of the fiber blank to start pressing. The time is controlled at 165 minutes to obtain a fiber blank with a unit wire diameter of 3.9μm.

[0153] (6) Stretching: The blank is stretched at 720°C to obtain a highly uniform light cone with a length of 75mm, a large end diameter of 27mm, and a small end diameter of 9mm.

[0154] Example 11: EMP-resistant fiber optic taper (metal wire material: 7075 aluminum alloy) - Replacement insert

[0155] The preparation method is as follows:

[0156] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and drawn into a single filament at 820°C for 45 minutes to obtain a drawn 2.6 μm single filament. 7075 aluminum alloy has good electrical conductivity and can effectively reflect and disperse electromagnetic waves, thereby providing a certain electromagnetic shielding performance. During high-temperature drawing, its mechanical properties support the structural requirements of optical fiber and can reduce the risk of deformation and strength reduction. 7075 aluminum alloy material can be selected to be drawn into a 2.6 μm metal wire at 760°C for 45 minutes. The light-absorbing glass rod was drawn into a 0.35 μm light-absorbing filament at 825°C for 50 minutes. The sheath glass with a refractive index of 1.47 at a wavelength of 594 nm was drawn into a structural filament at 830°C for 55 minutes to obtain a drawn 0.35 μm structural filament.

[0157] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 2The optical fiber arrangement is illustrated in the diagram. The optical fiber is arranged by inserting light-absorbing wires and structural wires in the gaps between the optical fiber monofilaments in alternating rows. The optical fiber monofilament in the center is replaced with a metal wire and then tied with cotton thread. The two ends are tied with non-flammable copper wire. Then, it is clamped on a wire drawing machine and drawn at 790°C for 55 minutes to form a primary multifilament with a side dimension of 1.02μm and a cross-section of regular hexagon.

[0158] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, tied with cotton thread, and tied with non-flammable copper wire at both ends. Then, it is clamped on a drawing machine and drawn at 800°C for 70 minutes to form a primary multifilament with a side dimension of 0.82μm and a regular hexagonal cross section.

[0159] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0160] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 65N is applied to the six directions of the fiber blank to start pressing. The time is controlled at 165 minutes to obtain a fiber blank with a unit wire diameter of 3.9μm.

[0161] (6) Stretching: The blank is stretched at 720°C to obtain a highly uniform light cone with a length of 75mm, a large end diameter of 27mm, and a small end diameter of 9mm.

[0162] Example 12: EMP-resistant fiber optic taper (wire material: 7075 aluminum alloy) - gap-type and replacement-type combined insertion

[0163] The preparation method is as follows:

[0164] (1) A core glass rod with a refractive index of 1.87 at a wavelength of 594 nm and a sheath glass tube with a refractive index of 1.47 at a wavelength of 594 nm were matched and drawn into a single filament at 820℃ for 45 minutes to obtain a 2.6 μm single filament. 7075 aluminum alloy has good electrical conductivity and can effectively reflect and disperse electromagnetic waves, thereby providing a certain electromagnetic shielding performance. During high-temperature drawing, its mechanical properties support the structural requirements of optical fiber and can reduce the risk of deformation and strength reduction. 7075 aluminum alloy material can be drawn into a 2.6 μm metal wire at 760℃ for 45 minutes. At the same time, 7075 aluminum alloy material can be drawn into a 0.35 μm metal wire at 770℃ for 80 minutes.

[0165] (2) Preparation of primary multifilaments: Arrange the monofilaments drawn in step (1) into a hexagonal prism with a regular hexagonal cross-section. Within the hexagonal prism, according to... Figure 3 The fiber arrangement diagram shows the fiber arrangement structure, in which wires are inserted into all the gaps between the fiber monofilaments, the fiber monofilament in the center is replaced with a metal wire, and then it is tied with cotton thread. The two ends are tied with non-flammable copper wire, and then it is clamped on a wire drawing machine and drawn at a temperature of 790°C for 55 minutes to form a primary multifilament with a side dimension of 1.02μm and a cross-section of regular hexagon.

[0166] (3) Preparation of secondary multifilament: The primary multifilament obtained in step (2) is arranged in a regular hexagonal structure, tied with cotton thread, and tied with non-flammable copper wire at both ends. Then, it is clamped on a drawing machine and drawn at 800°C for 70 minutes to form a primary multifilament with a side dimension of 0.82μm and a regular hexagonal cross section.

[0167] (4) The secondary multifilaments obtained in step (3) are arranged in a hexagonal close-packed manner and then bound together with copper wire to form a composite fiber bundle. The composite fiber bundle is then cut into 110mm fiber blanks with a side dimension of 40mm.

[0168] (5) Hot melt pressing: The fiber blank obtained in step (4) is placed into the hot melt pressing mold. The mold with the fiber blank is placed in the hot melt pressing furnace at a high temperature of 550℃. A pressure of 65N is applied to the six directions of the fiber blank to start pressing. The time is controlled at 165 minutes to obtain a fiber blank with a unit wire diameter of 3.9μm.

[0169] (6) Stretching: The blank is stretched at 720°C to obtain a highly uniform light cone with a length of 75mm, a large end diameter of 27mm, and a small end diameter of 9mm.

[0170] The shielding effectiveness (SE) and light transmittance (collimated light) results obtained from the electromagnetic pulse resistance tests of the fiber optic panels obtained in Examples 10-12 and Comparative Example 2 are summarized in Table 5.

[0171] Table 5

[0172]

[0173] As shown in Table 5, inserting 7075 aluminum alloy wires into the optical fiber significantly improves shielding effectiveness compared to traditional fiber optic panels (Comparative Example 2). Replacement insertion (Example 11) of the wires is more effective than gap insertion (Example 10), while a combination of both (Example 12) yields the best results. However, regardless of the method, the overall shielding effectiveness is lower than that of nichrome alloy wires. Compared to fiber optic panels with the same wire material, the electromagnetic shielding performance of the fiber optic cone is slightly inferior. The increased effective area occupied by the 7075 aluminum alloy wires in the fiber severely reduces optical performance, resulting in the worst light transmission efficiency. There is no significant difference in transmittance between the 7075 aluminum alloy wire and tapered fiber optics. Similarly, the transmittance of the 7075 aluminum alloy wire fiber optic cone is worse than that of the fiber optic panel.

[0174] As a core component of space probes, fiber optic imaging elements (FIIs) undertake the crucial task of acquiring optical signals from distant targets and transmitting them to sensors. Inserting metal wires with electromagnetic pulse (EMP) immunity into the FIIs is particularly important for mitigating electromagnetic interference in the space environment, especially near the sun or other strong electromagnetic sources. The presence of EMPs can cause signal distortion, transmission errors, or imaging errors, affecting the overall performance of the probe. Therefore, enhancing the EMP immunity of FIIs ensures stable operation of the probe in extreme space environments, especially in complex space exploration missions such as astronomical image acquisition and cosmic radiation monitoring. Through this coupling structure, the FIIs not only achieve efficient optical signal transmission but also provide a protective barrier against EMPs for the CMOS sensor, preventing image noise or signal loss caused by electromagnetic interference.

[0175] Numerous specific details are set forth in this specification. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some embodiments, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0176] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0177] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

[0178] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A method for fabricating an electromagnetic pulse-resistant fiber optic imaging element, characterized in that, Includes the following steps: S1 is formed by matching the core glass rod and the outer glass tube and drawing them into a single filament; S2 draws metal materials as metal rods into metal wires; S3 arranges the single wires obtained in step S1 into a hexagonal densest arrangement, and arranges the metal wires obtained in step S2 into wires according to the rules of intermittent insertion, replacement insertion, or a combination of intermittent and replacement insertion to obtain a primary composite rod, and then draws the primary composite rod into a primary multifilament with a regular hexagonal cross-section. S4 arranges the primary multifilaments obtained in step S3 into a secondary composite rod with a regular hexagonal cross-section, and draws the secondary composite rod into a secondary multifilament; S5 arranges the secondary multifilaments obtained in step S4 into a hexagonal close-packed arrangement, cuts them to a fixed length, and arranges them into plate segments. S6 The plate segment obtained in step S5 is hot-melted and pressed to obtain the electromagnetic pulse resistant fiber optic imaging element. In step S3, the intermittent insertion is as follows: the metal wire obtained in step S2 is inserted into all the gaps between the single filaments; the replacement insertion is as follows: the light-absorbing wire is inserted into the gaps between the single filaments in alternating rows, and structural wires with the same material composition as the glass are inserted into the remaining gaps, replacing the single filament located in the center position with the metal wire; the combined intermittent and replacement insertion is as follows: the metal wire is inserted into all the gaps between the single filaments, and at the same time, the metal wire replaces the single filament located in the center position.

2. The method for fabricating an electromagnetic pulse-resistant fiber optic imaging element as described in claim 1, characterized in that, Step S6 also includes stretching: the optical fiber board blank obtained by hot melt pressing is processed and stretched to obtain an optical cone.

3. The method for fabricating an electromagnetic pulse-resistant fiber optic imaging element as described in claim 2, characterized in that, In step S6, the electromagnetic pulse-resistant fiber optic imaging element is a light taper or a fiber optic panel; the unit wire diameter of the fiber optic panel or optical fiber board blank is 3.85-4.05μm.

4. An electromagnetic pulse-resistant fiber optic imaging element prepared by the method according to any one of claims 1-3, characterized in that, It includes an output end, an input end, and an optical fiber section disposed between the output end and the input end; the optical fiber section includes a plurality of optical fibers, the unit filament diameter of which is 3.85-4.05μm.

5. The electromagnetic pulse-resistant fiber optic imaging element as described in claim 4, characterized in that, The optical fiber imaging element is an optical fiber panel or an optical cone.

6. A high-energy ray imaging device, characterized in that, The high-energy X-ray imaging device includes the electromagnetic pulse-resistant fiber optic imaging element as described in claim 4; the electromagnetic pulse-resistant fiber optic imaging element includes an output end, an input end, and an optical fiber section disposed between the output end and the input end; the optical fiber section includes a plurality of optical fibers, the unit diameter of which is 3.85-4.05 μm.

7. A night vision device, characterized in that, The night vision device includes the electromagnetic pulse-resistant fiber optic image transmission element as described in claim 4; the electromagnetic pulse-resistant fiber optic image transmission element includes an output end, an input end, and an optical fiber portion disposed between the output end and the input end; the optical fiber portion includes a plurality of optical fibers, the unit filament diameter of which is 3.85-4.05 μm.

Images