Intelligent sensing reconfigurable metasurface laser protection structure and its fabrication method

Abstract

This invention provides an intelligent sensing reconfigurable metasurface laser protection structure and its fabrication method. The intelligent sensing reconfigurable metasurface laser protection structure comprehensively utilizes stealth coating materials, smoke stealth materials, and ablation-resistant materials, combined with ultrasonic motor technology, to propose an intelligent metasurface high-energy laser-resistant structure with four functions: a camouflage layer, an ablation-resistant layer, a sensing layer, and a driving layer. It achieves full coverage of the three-stage laser protection theory: "first, to remain undetected; if detected, to avoid being hit; if hit, to avoid being damaged." This results in a protective structure that resists high-energy lasers, extends the protection time against high-energy lasers, and improves the battlefield survivability and service performance of weapons and equipment. The intelligent sensing reconfigurable metasurface laser protection structure of this invention can be used in various service equipment across land, sea, air, and space facing potential laser weapon threats.

Description

Technical Field

[0001] This invention relates to the field of high-energy laser protection, specifically to an intelligent sensing reconfigurable metasurface laser protection structure and its fabrication method. Background Technology

[0002] Laser weapons, characterized by their high attack speed, concentrated energy, and strong destructive power, are gradually gaining traction in modern military applications. As a directed-energy weapon, the degree and mechanism of damage a laser weapon inflicts on a target are closely related to the efficiency of its output energy. For targets such as drones and rockets, laser weapons with output power in the tens of kilowatts are sufficient for destruction; however, for missiles or satellites, the laser output power needs to be increased to the megawatt level. Although the output power of laser weapons varies, they all cause severe pyrolysis, melting, perforation, and rupture effects on target structures, leading to the loss of their functionality. Therefore, researching and designing laser-resistant protective structures is urgently needed to improve the laser-resistant capabilities of modern military equipment.

[0003] The protection strategy against high-energy laser weapons mainly consists of three stages: first, to remain undetected; second, if detected, to avoid being hit; and third, if hit, to avoid being damaged. Current research indicates that materials capable of offering some protection against high-energy lasers primarily include laser-reflective coatings, ablation materials, and thermal insulation materials. Reflective coatings effectively reduce laser energy input, ablation materials dissipate heat through pyrolysis after laser irradiation, and thermal insulation materials can block heat transfer to some extent. However, these protection methods are relatively simplistic in their high-energy laser protection strategies, their mechanisms are relatively passive, and they are difficult to restore to their original protective effect after initial protection against a high-energy laser weapon. A single material and a single protection strategy cannot meet all three protection requirements. Therefore, the design and research of novel laser protection structures that meet the three-stage protection needs are urgently needed. Summary of the Invention

[0004] To address the problems of existing technologies, this invention provides an intelligent sensing reconfigurable metasurface laser protection structure and its preparation method. It comprehensively utilizes stealth coating materials, smoke stealth materials, and ablation-resistant materials, combined with ultrasonic motor technology, and has four functions: camouflage layer, ablation-resistant layer, sensing layer, and driving layer. It achieves full coverage of the three-stage theory of laser resistance and can be used in various service equipment in the sea, land, air, and space facing potential laser weapon threats.

[0005] This invention provides an intelligent sensing reconfigurable metasurface laser protection structure, comprising five layers: an outermost stealth coating material, a second layer of smoke screen stealth material, a third layer of ablation-resistant material, a fourth layer of sensing layer, and a fifth layer of ultrasonic motor drive layer. The second layer of smoke screen stealth material explodes to generate smoke when hit by a laser weapon. The fourth sensing layer employs temperature and pressure sensors to acquire the temperature and pressure in the third layer; when these values ​​exceed a threshold, the fifth layer of ultrasonic motor drive layer is activated. The ultrasonic motor drive layer is a reconfigurable metasurface that moves or rotates via an ultrasonic motor.

[0006] When the temperature rises to a certain level, the sensing layer in the fourth layer detects that the temperature threshold or pressure threshold has been reached, and will activate the ultrasonic motor in the fifth driving layer to drive the intelligent sensing reconfigurable metasurface to move or rotate, thereby preventing the already damaged local area from being continuously irradiated by high-energy laser.

[0007] In a further improvement, the ultrasonic motor drive layer includes an ultrasonic motor drive, a stator elastomer, a rotor, a rotor friction layer, and a piezoelectric ceramic film. The ultrasonic motor drive drives the rotor to rotate through the stator elastomer, thereby controlling the movement or rotation of the piezoelectric ceramic film.

[0008] In a further improvement, the ablation-resistant layer is a corrugated structure, a square honeycomb core structure with a centrally filled ablation-resistant material, or a hexagonal honeycomb core structure with a centrally filled ablation-resistant material.

[0009] This invention also provides a method for fabricating an intelligent sensing reconfigurable metasurface laser protection structure, comprising the following steps:

[0010] S1. The ultrasonic motor drive, stator elastomer, rotor, rotor friction layer and piezoelectric ceramic film are assembled into an ultrasonic motor drive layer by using organic adhesive bonding or soft soldering technology.

[0011] S2. A thermosensitive material is prepared as the sensing layer using a solid-state reaction process;

[0012] S3. A honeycomb core structure is prepared by laser cutting and brazing, and a honeycomb core filled with ablation-resistant, high-melting-point material is prepared by laser cutting, water jet cutting, and diamond wire saw cutting to obtain a honeycomb structure filled with ablation-resistant material as an ablation-resistant layer.

[0013] S4. A mixture of energetic explosive materials and smoke stealth materials is used as the lower camouflage layer;

[0014] S5. Prepare a stealth coating material as the upper camouflage layer.

[0015] S6. The lower camouflage layer, ablation-resistant layer, sensing layer and driving layer are connected by adhesive bonding. A stealth coating is applied to the lower camouflage layer as the upper camouflage layer. The assembled structure is left to stand at room temperature for 2 h to 6 h. After the stealth coating has completely solidified, the stains on the outer surface of the structure are removed to obtain an intelligent sensing reconfigurable metasurface laser protection structure.

[0016] Further improvements are made in step S1, where the piezoelectric ceramic film is prepared using a process of casting, lamination and hot pressing, debinding and sintering, and zoned polarization; the stator elastomer and rotor are prepared by machining. The piezoelectric ceramic film is manufactured from one of the following materials: lead zirconate titanate piezoelectric ceramic, lead antimony manganate ternary piezoelectric ceramic, lead antimony manganate quaternary piezoelectric ceramic, or sodium bismuth titanate; the stator elastomer is manufactured from one of the following materials: phosphor bronze, stainless steel, brass, silicon, or TC4 titanium alloy; the rotor is manufactured from metal materials, including hard aluminum, aluminum alloy, stainless steel, high-strength steel, or titanium alloy; and the rotor friction layer is manufactured from polymer materials, including polytetrafluoroethylene (PTFE), boron nitride-modified PTFE, polyimide, polyvinylidene fluoride (PVDF), polyphenylene ester-modified PVDF, or polyphenylene ester.

[0017] In a further improvement, the thermistor material mentioned in step S2 is selected as a negative temperature coefficient thermistor material, which is prepared from one of the following systems: Ca-Ce-Ti-WO, Mn-Co-O, Ni-Mn-O, and Ce-Mn-Si-O.

[0018] In a further improvement, the honeycomb core structure in step S3 is made from any one of carbon steel, stainless steel, titanium alloy, and aluminum alloy, and the ablation-resistant material is made from any one of alumina, silicon oxide, zirconium oxide, and silicon carbide.

[0019] In a further improvement, the energetic explosive material in step S4 is composed of one or more of the following: ammonium phosphate, Teflon, silicon dioxide, potassium chlorate, magnesium powder, aluminum powder, and magnesium-aluminum alloy powder; the smoke screen stealth material is composed of one or more of the following: hexachloroethane, polyvinylidene fluoride, benzene, polyvinyl chloride, metal oxides, ammonium perchlorate, and ammonium chloride.

[0020] In a further improvement, the stealth coating material described in step S5 is composed of one of the following: a photonic crystal material, a laser conversion or absorption material doped with rare earth elements, and a visible light camouflage material; the photonic crystal material includes lead telluride, tellurium, and silicon dioxide; the laser conversion or absorption material doped with rare earth elements is a yttrium system material and a samarium system material, including yttrium trioxide, samarium borate, and SmFeO3; the visible light camouflage material includes chromium trioxide.

[0021] The principle of this invention is as follows:

[0022] It is assembled from five parts: a laser stealth camouflage layer, a smokescreen-based lower camouflage layer, a heat-insulating and high-temperature-resistant ablation-resistant layer, a thermistor-based sensing layer, and an ultrasonic motor-driven layer. The primary function of the laser stealth camouflage layer is to achieve the first objective in the three-stage laser protection theory: avoid detection. The laser stealth camouflage layer reduces the probability of detection by optoelectronic devices. The lower camouflage layer's primary function is to achieve the second objective in the three-stage laser protection theory: avoid being hit. When irradiated by a laser, the energetic material in the lower camouflage layer explodes, igniting the smoke-generating material to produce a smoke screen, preventing continuous detection by optoelectronic devices and continuous laser irradiation. The heat-insulating and high-temperature-resistant ablation-resistant layer, the thermistor-based sensing layer, and the ultrasonic motor-driven layer primarily achieve the third objective in the three-stage laser protection theory: avoid being damaged. The heat-insulating and high-temperature-resistant ablation-resistant layer mainly extends the time for laser irradiation to reach the next layer, reduces the heat conducted to the next layer, and intercepts laser energy as much as possible. The main function of the thermistor sensing layer is that when laser energy is not conducted to the sensing layer, the resistance of the sensing layer remains relatively high. When laser energy is conducted to the sensing layer, the temperature of the sensing layer rises. When the temperature threshold is reached, a rapid response occurs, the resistance decreases, and power is supplied to the ultrasonic motor in the drive layer. The main function of the ultrasonic motor drive layer is that when the ultrasonic motor is powered, the rotor will translate or rotate under the pressure generated by the laser impact on the structure. This changes the laser irradiation position, shifting from continuously irradiating the same area to continuously irradiating the area not irradiated by the laser, thereby extending the structure's resistance to high-energy lasers.

[0023] The beneficial effects of this invention are as follows:

[0024] 1. By adopting intelligent sensing and reconfigurable metasurface anti-laser technology, the three-stage theory of anti-laser is fully covered: "first, not to be detected; if detected, not to be hit; if hit, not to be destroyed." This achieves the effect of protecting the structure against various high-energy lasers and extending the time of protection against high-energy lasers, which can greatly improve the battlefield survivability and service performance of weapons and equipment.

[0025] 2. Depending on the application and processing method, the intelligent sensing reconfigurable metasurface laser-resistant sandwich structure can be prepared into regular shapes or other specific shapes to facilitate modular assembly and splicing, thereby achieving protection against high-energy laser weapons for large-sized or irregularly sized equipment.

[0026] 3. Depending on the specific protection requirements of different laser weapons, the thickness of certain layers can be altered, or some layers can be added or removed. For example, for low-power laser weapons that primarily cause photoelectric interference, the camouflage layer can be modified to use an absorptive material to absorb the laser beam. For high-power laser weapons, the thickness of the ablation-resistant layer can be increased, the burn-through time of the ablation-resistant layer can be extended, more response time can be provided to the thermosensitive layer, or the thermosensitive layer material can be replaced with one that has a lower temperature threshold and a faster response, thereby achieving a specific effect against a particular type of laser weapon. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A schematic diagram of the basic unit and each layer of the intelligent sensing reconfigurable metasurface laser-resistant sandwich structure;

[0029] Figure 2 A schematic diagram of laser irradiation on a reconfigurable metasurface laser-resistant sandwich structure for intelligent sensing, and a schematic diagram of the working of its driving layer;

[0030] Figure 3 A schematic diagram of laser irradiation of the basic unit of the intelligent sensing reconfigurable metasurface laser-resistant sandwich structure and a schematic diagram of the working of its driving layer;

[0031] The layers are: 1. Upper camouflage layer; 2. Lower camouflage layer; 3. Anti-ablation layer; 4. Sensing layer; 5. Driving layer; 6. Laser beam. Implementation

[0032] In the description of this invention, it should be noted that, unless otherwise specified, terms such as "core" of the ablation-resistant layer and "ultrasonic motor" of the driving layer should be interpreted broadly. For example, "core" can be a corrugated core, a square honeycomb core, a hexagonal honeycomb core, etc., which are mainly composed of surface elements; or it can be a pyramid truss core, a tetrahedron, a Kagome, etc., which are mainly composed of line elements in a three-dimensional lattice truss structure. The ultrasonic motor can be a linear ultrasonic motor, such as a rectangular plate linear ultrasonic motor, a V-shaped linear ultrasonic motor, or a high-power sandwich-type longitudinal bending composite linear ultrasonic motor; or it can be a rotary ultrasonic motor, such as a traveling wave rotary ultrasonic motor, a standing wave rotary ultrasonic motor, and a longitudinal torsion composite rotary ultrasonic motor. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific working conditions.

[0033] Please see Figure 1The intelligent sensing reconfigurable laser-resistant metasurface structure described in this invention mainly consists of five different layers: an upper camouflage layer, a lower camouflage layer, an anti-ablation layer, a sensing layer, and a driving layer. The upper camouflage layer 1 is primarily a laser stealth coating material, used to absorb laser light or reduce its reflectivity, thereby reducing the likelihood of detection and achieving battlefield stealth. The lower camouflage layer 2 contains energetic materials and smoke-screen materials. Its main function is that when irradiated by a laser, the laser penetrates the upper camouflage layer, causing an energetic explosion that ignites and rapidly spreads the smoke-screen material, which quickly generates smoke to shield the laser and interfere with detection by equipment. The anti-ablation layer 3 mainly consists of a sandwich structure core and a high-temperature resistant, anti-ablation filling material. The sandwich structure core primarily provides structural support and stability, while the high-temperature resistant, anti-ablation filling material extends the ablation time and facilitates downward heat conduction. Sensing layer 4 is primarily composed of a negative temperature coefficient thermistor. Its main function is to reduce the resistance of the thermistor when it receives heat conducted from the ablation-resistant layer and the temperature reaches a certain threshold, thus supplying power to the driving layer. When not exposed to laser irradiation, the thermistor's resistance is high, and the driving layer is de-energized. Driving layer 5 is mainly composed of an ultrasonic motor. When the structure is continuously impacted by a laser, and the driving layer is powered, the ultrasonic motor operates. The rotor drives the upper structure to translate and rotate, thereby changing the laser irradiation position and preventing continuous laser irradiation of the same location, increasing the structure's laser resistance duration. Figure 2 and Figure 3 As shown, when the laser beam 6 irradiates the intelligent sensing reconfigurable anti-laser metasurface structure, it penetrates the stealth coating and reaches the lower camouflage layer. The energetic material explodes, and under continuous irradiation, the temperature is conducted to the sensing layer, which eventually causes the ultrasonic motor to start, driving the ultrasonic motor to perform translation and rotation. This inevitably leads to continuous ablation of the same position, resulting in a laser beam ablation trajectory on the structure surface.

[0034] Therefore, intelligent sensing reconfigurable laser-resistant metasurface structures can achieve three different protection targets in three stages of laser resistance.

[0035] An implementation example of the intelligent sensing reconfigurable laser-resistant metasurface structure described in this invention is as follows:

[0036] S1. Piezoelectric ceramic films are prepared using processes such as casting, lamination and hot pressing, debinding and sintering, and partitioned polarization; stator elastomers and rotors are prepared by machining; and suitable friction materials are selected as rotor friction layers. Finally, they are assembled into ultrasonic motor drive layers using connection processes such as organic adhesive bonding or soft soldering.

[0037] S2. A thermosensitive material is prepared using a solid-state reaction process to serve as the sensing layer, which can respond quickly to rapid temperature changes.

[0038] S3. A square honeycomb core structure is prepared using laser cutting and brazing. Appropriately sized ablation-resistant, high-melting-point material is then cut using laser cutting, waterjet cutting, and diamond wire sawing to fill the square honeycomb core. The resulting ablation-resistant material fills the square honeycomb structure as an ablation-resistant layer.

[0039] S4. A mixture of energetic explosive material and smoke stealth material is used as the lower camouflage layer. Its function is that when laser irradiation occurs, the energetic material explodes, and the explosion disperses the smoke stealth material into smoke, thereby interfering with the detection system.

[0040] S5. Prepare a stealth coating material as an upper camouflage layer. Its main function is to absorb visible light and infrared light, reducing the possibility of being detected by the detection system.

[0041] S6. The lower camouflage layer, ablation-resistant layer, sensing layer, and driving layer are connected by adhesive bonding, and a stealth coating is applied to the lower camouflage layer as the upper camouflage layer. The assembled structure is then left to stand at room temperature for 2 to 6 hours until the stealth coating has completely solidified. After this process, the dirt on the outer surface of the structure is removed.

[0042] An embodiment of the intelligent sensing reconfigurable laser-resistant metasurface structure described in this invention is as follows:

[0043] S1. Piezoelectric ceramic films are prepared using processes such as casting, lamination and hot pressing, debinding and sintering, and partitioned polarization; stator elastomers and rotors are prepared by machining; and suitable friction materials are selected as rotor friction layers. Finally, they are assembled into ultrasonic motor drive layers using connection processes such as organic adhesive bonding or soft soldering.

[0044] S2. A thermosensitive material is prepared using the sol-gel hydrothermal method as the sensing layer, which can respond quickly to rapid temperature changes.

[0045] S3. A three-dimensional lattice truss core structure is prepared using investment casting, perforated mesh stamping-brazing, expanded metal mesh folding-brazing, three-dimensional weaving, additive manufacturing, extrusion wire cutting, and lap welding methods. Appropriately sized ablation-resistant, high-melting-point materials are then cut using laser cutting, waterjet cutting, and diamond wire sawing to fill the three-dimensional lattice truss core. The final ablation-resistant material-filled three-dimensional lattice truss core structure serves as the ablation-resistant layer.

[0046] S4. A mixture of energetic explosive material and smoke stealth material is used as the lower camouflage layer. Its function is that when laser irradiation occurs, the energetic material explodes, and the explosion disperses the smoke stealth material into smoke, thereby interfering with the detection system.

[0047] S5. Prepare a stealth coating material as an upper camouflage layer. Its main function is to absorb visible light and infrared light, reducing the possibility of being detected by the detection system.

[0048] S6. The lower camouflage layer, ablation-resistant layer, sensing layer, and driving layer are connected by adhesive bonding, and a stealth coating is applied to the lower camouflage layer as the upper camouflage layer. The assembled structure is then left to stand at room temperature for 2 to 6 hours until the stealth coating has completely solidified. After this process, the dirt on the outer surface of the structure is removed.

[0049] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on its differences from other embodiments. In particular, for the device embodiments, the above descriptions are merely preferred embodiments of the present invention. Since they are fundamentally similar to the method embodiments, the descriptions are relatively simple, and relevant parts can be referred to the descriptions of the method embodiments. The above descriptions are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention, without departing from the principle of the present invention, should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A smart sensing reconfigurable metasurface laser protection structure, characterized in that: It comprises five layers: an outermost stealth coating, a second layer of smoke screen stealth material, a third layer of ablation-resistant material, a fourth sensing layer, and a fifth layer of ultrasonic motor drive. The second layer of smoke screen stealth material explodes to generate smoke when hit by a laser weapon. The fourth sensing layer uses temperature and pressure sensors to acquire the temperature and pressure from the third layer; when these exceed a threshold, the fifth layer of ultrasonic motor drive is activated. The ultrasonic motor drive layer is a reconstructed metasurface that moves or rotates via an ultrasonic motor. The ultrasonic motor drive layer includes an ultrasonic motor drive, a stator elastomer, a rotor, a rotor friction layer, and a piezoelectric ceramic film. The ultrasonic motor drive drives the rotor to rotate via the stator elastomer, thereby controlling the movement or rotation of the piezoelectric ceramic film.

2. The intelligent sensing reconfigurable metasurface laser protection structure according to claim 1, characterized in that: The ablation-resistant layer is a corrugated structure, a square honeycomb core structure with a central ablation-resistant material, or a hexagonal honeycomb core structure with a central ablation-resistant material.

3. A method for fabricating the intelligent sensing reconfigurable metasurface laser protection structure as described in claim 1, characterized in that... Includes the following steps: S1. The ultrasonic motor drive, stator elastomer, rotor, rotor friction layer and piezoelectric ceramic film are assembled into an ultrasonic motor drive layer by using organic adhesive bonding or soft soldering technology. S2. Thermistor materials are prepared in the sensing layer using a solid-state reaction process; S3. A honeycomb core structure is prepared by laser cutting and brazing, and the honeycomb core structure filled with ablation-resistant, high-melting-point material is cut by laser cutting, water jet cutting or diamond wire saw cutting to obtain an ablation-resistant honeycomb core structure as an ablation-resistant layer. S4. A mixture of energetic explosive materials and smoke-screen stealth materials is used as the second layer; S5. Prepare a stealth coating material as the outermost layer.

4. The method for fabricating the intelligent sensing reconfigurable metasurface laser protection structure according to claim 3, characterized in that: The preparation method also includes S6, connecting the second layer, the ablation-resistant layer, the sensing layer and the ultrasonic motor drive layer by bonding, and applying a stealth coating material to the second layer as the outermost layer. The assembled structure is left to stand at room temperature for 2 h to 6 h. After the stealth coating material has completely solidified, the stains on the outer surface of the structure are removed to obtain an intelligent sensing reconfigurable metasurface laser protection structure.

5. The method for fabricating the intelligent sensing reconfigurable metasurface laser protection structure according to claim 3, characterized in that: In step S1, the piezoelectric ceramic film is prepared by casting, lamination and hot pressing, debinding and sintering, and partitioned polarization. The stator elastomer and rotor are prepared by machining.

6. The method for fabricating the intelligent sensing reconfigurable metasurface laser protection structure according to claim 4 or 5, characterized in that: The piezoelectric ceramic film is manufactured from one of the following materials: lead zirconate titanate piezoelectric ceramic, lead antimony manganate ternary piezoelectric ceramic, lead antimony manganate quaternary piezoelectric ceramic, and sodium bismuth titanate; the stator elastomer is manufactured from one of the following materials: phosphor bronze, stainless steel, brass, silicon, and TC4 titanium alloy; the rotor is manufactured from a metal material, including one of the following materials: hard aluminum, aluminum alloy, stainless steel, high-strength steel, and titanium alloy; the rotor friction layer is manufactured from a polymer material, including one of the following materials: polytetrafluoroethylene, boron nitride modified polytetrafluoroethylene, polyimide, polyvinylidene fluoride, polyphenylene ester modified polyvinylidene fluoride, and polyphenylene ester.

7. The method for fabricating the intelligent sensing reconfigurable metasurface laser protection structure according to claim 3, characterized in that: The thermistor material mentioned in step S2 is a negative temperature coefficient thermistor material, which is prepared from one of the following systems: Ca-Ce-Ti-WO, Mn-Co-O, Ni-Mn-O, and Ce-Mn-Si-O.

8. The method for fabricating an intelligent sensing reconfigurable metasurface laser protection structure according to claim 3, characterized in that: The honeycomb core structure in step S3 is made of any one of carbon steel, stainless steel, titanium alloy, and aluminum alloy, and the ablation-resistant material is made of any one of alumina, silicon oxide, zirconium oxide, and silicon carbide.

9. The method for fabricating the intelligent sensing reconfigurable metasurface laser protection structure according to claim 3, characterized in that: The energetic explosive material mentioned in step S4 is composed of one or more of the following: ammonium phosphate, Teflon, silicon dioxide, potassium chlorate, magnesium powder, aluminum powder, and magnesium-aluminum alloy powder; the smoke screen stealth material is composed of one or more of the following: hexachloroethane, polyvinylidene fluoride, benzene, polyvinyl chloride, metal oxide, ammonium perchlorate, and ammonium chloride.

10. The method for fabricating the intelligent sensing reconfigurable metasurface laser protection structure according to claim 3, characterized in that: The stealth coating material mentioned in step S5 is composed of one of the following: a photonic crystal material, a laser conversion or absorption material doped with rare earth elements, and a visible light camouflage material; the photonic crystal material includes lead telluride, tellurium, and silicon dioxide; the laser conversion or absorption material doped with rare earth elements is a yttrium system material and a samarium system material, including yttrium trioxide, samarium borate, and SmFeO3; the visible light camouflage material includes chromium trioxide.

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