Infrared and millimeter wave compatible stealth structure

Abstract

The application provides an infrared and millimeter wave compatible stealth structure, and belongs to the field of stealth.The stealth structure comprises an optical infrared stealth layer and a millimeter wave stealth layer;the optical infrared stealth layer is arranged on the upper surface of the millimeter wave stealth layer in a vacuum evaporation plating film mode;the visible light brightness contrast value of the optical infrared stealth layer is less than or equal to 0.15, the reflectivity to near infrared is greater than or equal to 40%, and the reflectivity to medium and far infrared is greater than or equal to 70%;and the millimeter wave stealth layer is used for absorbing millimeter waves to realize stealth in the millimeter wave band.The application realizes infrared and millimeter wave stealth simultaneously, and the structure is light and thin, which can be conveniently attached to the target surface by means of sticking and the like to reduce the probability of the target being detected.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of invisibility, in particular to an infrared and millimeter wave compatible invisibility structure. BACKGROUND

[0002] Infrared radiation is a kind of electromagnetic wave outside the visible light, with a wavelength of 0.78-1000um. According to its wavelength, it can be divided into near infrared l-2.7um, mid-infrared 3-5um and far infrared 8-14um. With the rapid development of military science and technology, modern infrared reconnaissance and sighting technology has reached a very high level. Photoelectric imaging satellites can obtain visible light images and infrared images with a resolution of 0.1m, and can take pictures of ground targets in complete darkness, especially suitable for monitoring the movement of tanks, armored vehicles and mobile ballistic missiles, which seriously threatens the safety of various military targets and weapons.

[0003] Millimeter wave refers to the part of the electromagnetic spectrum with a frequency of 30-300GHz, corresponding to a wavelength of 1-10mm. Compared with microwaves, millimeter waves have shorter wavelengths. In recent years, with the rapid development of millimeter wave devices and millimeter wave sources, millimeter wave technology has made great progress in radar, communication, radiation measurement and measuring instruments.

[0004] In summary, in order to counter the threat of photoelectric reconnaissance guidance, it is necessary to develop compatible invisibility in multiple bands such as infrared and millimeter wave for military targets. However, the current invisibility structure can only be invisible in infrared or millimeter wave, and cannot meet the needs of infrared and millimeter wave invisibility at the same time. SUMMARY

[0005] The purpose of the present application is to provide an infrared and millimeter wave compatible invisibility structure, which can realize infrared and millimeter wave invisibility at the same time, and the invisibility structure has the characteristics of lightness and thinness.

[0006] To achieve the above purpose, the present application provides the following scheme:

[0007] An infrared and millimeter wave compatible invisibility structure, comprising: an optical infrared invisibility layer and a millimeter wave invisibility layer.

[0008] The optical infrared invisibility layer is arranged on the upper surface of the millimeter wave invisibility layer by vacuum evaporation plating, the visible light brightness contrast value of the optical infrared invisibility layer is less than or equal to 0.15, the reflectivity to near infrared is greater than or equal to 40%, and the reflectivity to mid-infrared is greater than or equal to 70%.

[0009] The millimeter wave invisibility layer is used to absorb millimeter waves to achieve invisibility in the millimeter wave band.

[0010] Optionally, the optical infrared invisibility layer is a photonic crystal film.

[0011] Optionally, the optical infrared stealth layer comprises YbF3 film and ZnSe film arranged alternately.

[0012] Optionally, the color difference between the optical infrared stealth layer and the background in a jungle environment is less than or equal to 2.

[0013] Optionally, the millimeter wave stealth layer is a metamaterial wave absorber.

[0014] Optionally, the metamaterial wave absorber comprises a flexible conductive transparent film and a flexible transparent polydimethylsiloxane medium.

[0015] Optionally, the lower surface of the millimeter wave stealth layer is pasted on the surface of the equipment to be stealthed.

[0016] According to the specific embodiments of the present application, the following technical effects are provided:

[0017] The present application realizes infrared stealth in the infrared wave band through the optical infrared stealth layer, reduces or changes the infrared radiation characteristics of the target, reduces the action distance of the infrared detection system on the target, realizes millimeter wave stealth in the millimeter wave band through the millimeter wave stealth layer, realizes composite stealth by using millimeter wave stealth materials with different transmittances and infrared stealth materials with low emissivity, has the infrared emissivity required for infrared stealth while absorbing millimeter waves, and does not interfere with each other, has the characteristics of thinness and lightness, and can be conveniently applied to the surface of the target by pasting and the like, thereby reducing the probability of being detected. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0019] Figure 1 Fig. 1 is a schematic diagram of the infrared and millimeter wave compatible stealth structure of the present application.

[0020] Symbol explanation:

[0021] Optical infrared stealth layer-1, millimeter wave stealth layer-2, equipment to be stealthed-3. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of the present application.

[0023] The present application aims to provide an infrared and millimeter wave compatible stealth structure, which has the required infrared emissivity for infrared stealth while absorbing millimeter waves by cooperation of the optical infrared stealth layer and the millimeter wave stealth layer, and has the characteristics of thinness and lightness.

[0024] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0025] As shown in Figure 1 The present application provides an infrared and millimeter wave compatible stealth structure, which comprises an optical infrared stealth layer 1 and a millimeter wave stealth layer 2.

[0026] The optical infrared stealth layer 1 is arranged on the upper surface of the millimeter wave stealth layer 2. The lower surface of the millimeter wave stealth layer 2 is pasted on the surface of the equipment to be stealthed 3. Obviously, the millimeter wave stealth layer 2 can also be arranged on the surface of the equipment to be stealthed 3 in other ways, and the present application is not limited to the pasting way.

[0027] Infrared stealth is not just to pursue low emissivity. For ground targets, the main purpose is to make the emissivity consistent with the background. Usually, infrared camouflage is used to make the emissivity distribution of each patch of the target consistent with the background to achieve infrared stealth. In the present embodiment, the optical infrared stealth layer 1 has a visible light brightness contrast value less than or equal to 0.15, a near-infrared reflectivity greater than or equal to 40%, and a mid-far infrared reflectivity greater than or equal to 70%. The color difference of the optical infrared stealth layer 1 with the background in a jungle environment is less than or equal to 2.

[0028] The optical infrared stealth layer 1 of the present application can use the infrared stealth material commonly used in the prior art, which has a visible light brightness contrast value less than or equal to 0.15, a near-infrared reflectivity greater than or equal to 40%, a mid-far infrared reflectivity greater than or equal to 70%, and a color difference with the background in a jungle environment less than or equal to 2.

[0029] As a specific embodiment, the optical infrared stealth layer 1 is a photonic crystal film. The photonic crystal film is arranged on the upper surface of the millimeter wave stealth layer by vacuum evaporation plating. The optical infrared composite stealth layer is a photonic crystal film structure, which is made by a vacuum evaporation plating method, has spectral selectivity, does not cause accumulation of human body heat, and is transparent to millimeter waves, without affecting the absorption performance of the millimeter wave absorbing base cloth below.

[0030] As another specific embodiment, the optical infrared stealth layer 1 includes YbF3 films and ZnSe films arranged alternately and superimposed.

[0031] As another specific embodiment, the optical infrared stealth layer 1 is composed of aluminum nanowires, a transparent polymer, a first dispersant, and a second dispersant. The optical infrared stealth layer 1 is coated on the upper surface of the millimeter wave stealth layer by one or more of spraying, doctor blade coating, roller coating, or direct immersion, for example. The thickness of the optical infrared stealth layer 1 is 5-20 um. After coating, drying is performed at a temperature below 60°C for 24-72 h. The diameter of the aluminum nanowires in the optical infrared stealth layer 1 is 5-100 nm, and the length is 5-50 um. The aluminum nanowires themselves have excellent light transmission. In this embodiment, the high aspect ratio of the silver nanowires is beneficial to forming a high-performance network structure in the low-emissivity coating, greatly increasing the visible light transmittance of the optical infrared stealth layer 1, and improving the stealth effect.

[0032] Since the infrared stealth coating is generally very thin, if it has transparency to millimeter waves and does not absorb or reflect millimeter waves, it can be coated on a target with millimeter wave stealth, thereby realizing infrared and millimeter wave composite stealth.

[0033] The millimeter wave stealth layer 2 is used to absorb millimeter waves to achieve stealth in the millimeter wave band. In this embodiment, the millimeter wave stealth layer 2 is a metamaterial absorber. By optimizing the structure of the absorber unit, the absorption performance of different millimeter wave bands is realized. The metamaterial absorber includes a flexible conductive transparent film ITO and a flexible transparent polydimethylsiloxane PDMS medium.

[0034] Since infrared and millimeter waves are not in the same band, the present application proposes an infrared and millimeter wave composite stealth material. The optical infrared stealth layer 1 realizes stealth in the infrared band, and the millimeter wave stealth layer 2 realizes stealth in the millimeter wave band. The millimeter wave stealth material with different transmittance and the infrared stealth material with low emissivity are designed into an infrared camouflage to realize a composite stealth structure. While absorbing millimeter waves, the infrared emissivity required for infrared stealth is achieved. The two do not interfere with each other, have the characteristics of thinness and lightness, and can be easily applied to the surface of equipment by pasting and the like. The deficiencies of existing stealth means are improved.

[0035] The principles and implementation manners of the present application are described by using specific examples in the present application, and the above examples are only used to help understand the method of the present application and its core idea; meanwhile, for the general technical personnel in the art, the specific implementation manners and application ranges will be changed according to the idea of the present application. In conclusion, the content of the present specification should not be understood as the limitation of the present application.

Claims

1. A stealth structure compatible with both infrared and millimeter-microwave radiation, characterized in that, The infrared and millimeter-wave compatible stealth structure includes: an optical infrared stealth layer and a millimeter-wave stealth layer; The optical infrared stealth layer is deposited on the upper surface of the millimeter-wave stealth layer using a vacuum evaporation coating method. The visible light brightness contrast value of the optical infrared stealth layer is less than or equal to 0.15, the reflectivity of near-infrared is greater than or equal to 40%, and the reflectivity of mid- and far-infrared is greater than or equal to 70%. The color difference between the optical infrared stealth layer and the background in a jungle environment is less than or equal to 2. The millimeter-wave stealth layer is used to absorb millimeter waves to achieve stealth in the millimeter-wave band; the millimeter-wave stealth layer is a metamaterial absorber, and by optimizing the structural unit of the absorber, the absorption performance of different millimeter-wave bands is achieved; the metamaterial absorber includes a flexible conductive transparent film and a flexible transparent polydimethylsiloxane medium.

2. The infrared and millimeter-microwave compatible stealth structure according to claim 1, characterized in that, The optical infrared stealth layer is a photonic crystal thin film.

3. The infrared and millimeter-microwave compatible stealth structure according to claim 1, characterized in that, The optical infrared stealth layer comprises alternating layers of YbF3 film and ZnSe film.

4. The infrared and millimeter-microwave compatible stealth structure according to claim 1, characterized in that, The lower surface of the millimeter-wave stealth layer is adhered to the surface of the equipment to be stealthed.

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