CN108174592A - Design method of overlapping ring grid based on random center position and variable diameter - Google Patents

Abstract

Based on center location, annulus grid design method Chong Die with variable diameters belongs to the electromangnetic spectrum field of optical window at random, overlapping annulus grid can random parameter include diameter and cycle parameter.The present invention is using the random fashion of random diameter and cycle parameter simultaneously, the random of period is realized by the random of center location, the random areas of center location is respectively the polygonal regions such as quadrangle, hexagon and border circular areas, and diameter parameters carry out at random in the symmetrical range centered on initial diameter value.The center location for each annulus unit being overlapped in annulus grid is randomized the overlapping annulus grid to obtain having random structure in fixed area, the period of annulus in grid structure and diameter can effectively be randomized by this random device.Relative to the grid of traditional periodic structure, the overlapping annulus grid based on this random device can effectively be homogenized the high level diffraction energy of grid, and the distribution for making stray light is more uniform, significantly reduces the influence to image quality.

Description

Design method of overlapping ring grid based on random center position and variable diameter

technical field

The invention belongs to the field of electromagnetic shielding of optical windows, and in particular relates to a design method of overlapping circular ring grids based on random center positions and variable diameters.

Background technique

With the rapid development of wireless devices, electromagnetic waves are widely used in all aspects of production and life, and the space electromagnetic environment is becoming more and more complex, especially in the microwave and radio bands. Therefore, the shielding of electromagnetic interference has gradually become an urgent problem in many fields, such as the precision detection of optical windows, aerospace devices, medical devices, and electronic displays. The electromagnetic shielding of the optical window needs to meet the high transmittance of visible light and infrared bands and the strong electromagnetic shielding performance of microwave and radio bands at the same time. In order to solve the electromagnetic shielding problem of optical windows, many methods have been proposed, such as ITO transparent conductive film, frequency selective surface (FSS), graphene film, nano-silver wire, metal grid, etc. The metal grid with a submillimeter period can transmit visible light and infrared light with a wavelength shorter than its period, and at the same time shield microwave and radio electromagnetic waves with a wavelength longer than its period, and has been widely used in the field of electromagnetic shielding for optical windows. .

The periodic structure of the traditional periodic grid structure metal grid plays the role of a two-dimensional diffraction grating in the optical band, which makes the grid form a concentrated distribution of optical diffraction patterns on the image plane during optical imaging, and concentrated distribution of high-order diffraction The energy will reduce the imaging quality of the optical detection device and affect the normal detection. In serious cases, it will cause the detection of false targets, which is extremely harmful. In order to solve the problem of grid diffraction characteristics, many grids with different structures have been proposed.

Patent CN1889822 "Electromagnetic Shielding Optical Window with Ring Metal Grid Structure" describes metal grid units with a ring shape, which are secretly arranged in a two-dimensional orthogonal arrangement to form a metal grid array. This structure is conducive to optical Improving the imaging quality of the behind-the-window imaging system.

The patent CN101222839 "an electromagnetic shielding optical window with a double-layer circular metal grid structure" describes an electromagnetic shielding optical window composed of two layers of circular metal grids loaded on both sides of the optical window to solve the problem of high light transmittance. And the problem that the strong electromagnetic shielding performance cannot be taken into account at the same time.

The patent CN2233113 "Moiré-free electromagnetic shielding observation window" adopts two layers of metal mesh with different numbers placed in parallel, and there is a certain angle between their warp and weft, so as to overcome the moiré phenomenon and achieve a clearer view.

Patent CN103763907A "Electromagnetic shielding light window based on two-dimensional orthogonal distribution of tangent rings and inscribed sub-ring arrays" describes a metal grid structure composed of two-dimensional orthogonally distributed basic rings and their inscribed sub-rings. This structure can realize the deep optimization of grid high-order diffraction energy.

Patent CN103763901A "Electromagnetic shielding optical window based on triangular distribution of tangent rings and inscribed sub-ring arrays" describes a kind of metal rings containing inscribed sub-ring structures loaded on the surface of the transparent substrate of the optical window in an equilateral triangle arrangement. The grid array is formed, and this structure can significantly reduce the non-uniformity of the light intensity distribution of the high-order diffraction of the grid, and has less influence on the imaging.

Patent CN103763896A "Electromagnetic shielding light window of double-layer staggered multi-period metal ring nested array" describes an electromagnetic shielding light window composed of two layers of metal grids staggered, which significantly reduces the intensity distribution of grid diffraction. Inhomogeneity, reducing the impact on imaging.

Patent CN102723126A "A Patterned Transparent Conductive Film Based on Random Grid" describes a transparent conductive film whose conductive region is composed of irregularly shaped random grids, and has the advantage of not generating moiré fringes.

Patent CN102902856A "Random grid design method of metal mesh conductive film, conductive film and its manufacturing method" describes a periodic grid composed of regular graphics to generate a random grid composed of irregular polygons to avoid the generation of Moiré fringes and to eliminate differences in transmittance.

Patent CN104950365A "An Optically Transparent Frequency Selective Surface Structure and Manufacturing Method" describes a frequency selective surface structure based on a random crack mask. The advantage is that it can avoid the problem of reducing light transmittance due to the increase of metal line width and can achieve homogenization. The purpose of high-order diffraction energy.

Patents 1-6 are all traditional metal grids with periodic structure. Traditional structure grids have a period of fixed size, so the high-order diffraction energy distribution in the optical band is relatively concentrated, which seriously reduces the imaging quality. In patents 7-9, A random grid design method is proposed, and a randomly distributed polygonal grid structure is generated. However, compared with the polygonal structure, the ring structure has more advantages in homogenizing the high-order diffraction energy of the grid due to its own symmetry. The present invention combines the idea of rings and randomness to propose a design method for overlapping ring grids based on random center positions and variable diameters. This random method randomizes the period and diameter parameters of the grid at the same time. The randomization effect of the grid structure based on the double-parameter random method is better. The overlapping circular ring grid based on this random method achieves the purpose of homogenizing the high-order diffraction energy by changing the diameter and period of the circular ring units in the grid. Advanced The impact of sub-diffraction energy on imaging quality is significantly reduced, and the grid can simultaneously achieve high transparency in the optical band and strong electromagnetic shielding performance in the microwave band.

Contents of the invention

The purpose of the present invention is to provide a design method based on the random center position and variable diameter of overlapping ring grids to improve the concentrated distribution of high-order diffraction energy of traditional periodic structure metal grids and achieve high light transmittance at the same time Low imaging quality impact and strong electromagnetic shielding performance.

To achieve the above object, the present invention provides the following technical solutions:

The idea of the present invention is to combine the two ideas of ring structure and random structure, and propose a design method for overlapping ring grids based on random center position and variable diameter, so as to achieve the purpose of homogenizing the high-order diffraction energy of the grid, and at the same time ensure that the grid The grid has high light transmittance and strong electromagnetic shielding performance.

A stochastic method based on the diameter parameter of overlapping ring grids and the periodic parameters with circular random regions, characterized in that the grid is composed of ring units, on the basis of overlapping ring grids arranged in periodic arrays Through randomization, the random parameters of the grid include diameter 2 R and period g .

The random method based on the diameter parameter of overlapping ring grid and the period parameter with circular random area according to claim 1, it is characterized in that, comprises the steps:

(1) Arrange the ring units in a 60° periodic array, in order to ensure that the rings overlap each other;

(2) Generate a fixed-sized area centered on the center of each circle at the center of each circle;

(3) Generate random points in each fixed area, which is the random center position;

(4) Randomize the diameter parameter 2 R of each circle within the symmetrical range [2 R _{0 -Δ} R ,2 R ₀ +Δ R ] of the initial diameter parameter 2 R 0 .

According to claim 1, the design method of overlapping circular ring grids based on random center positions and variable diameters is characterized in that the ratio g / 2R of the period g of the grid to the diameter 2R is greater than 1.

According to claim 1, the method for designing overlapping circular ring grids based on random center positions and variable diameters is characterized in that the random mode of the grids is randomization of period g and diameter 2R parameters at the same time.

According to claim 1, the overlapping ring grid design method based on the random center position and variable diameter is characterized in that the random range of the period g can be adjusted by changing the size of the fixed area, and the range of the fixed area needs to be smaller than the ring unit area range.

According to claim 1, based on random center position and variable diameter overlapping ring grid design method, it is characterized in that, in step 1, the fixed area is a polygonal area such as a quadrangle, a hexagon, and a circle.

According to claim 1, the design method of overlapping ring grids based on random center position and variable diameter is characterized in that the random mode of period g and diameter 2 R is uniform distribution.

The present invention has following novelty and remarkable effect:

The present invention proposes a design method of overlapping ring grids based on random center positions and variable diameters. This random method can effectively randomize the period and diameter parameters of overlapping ring grids. By reasonably controlling grid parameters and The random range of parameters is used to ensure that the adjacent ring units of the grid are overlapped and electrically connected to each other, and an overlapping ring grid structure with random diameter and period can be generated.

The present invention proposes a design method of overlapping ring grids based on random center positions and variable diameters. Compared with traditional periodic structure grids, the overlapping ring grids based on this random method effectively combine the The period and ring diameter are randomized to generate overlapping ring grids with ring unit structures with different orientations and different diameters. This random grid structure can effectively homogenize the concentratedly distributed high-order diffraction energy and reduce the impact on imaging quality. Influence, and at the same time can achieve high light transmittance and strong electromagnetic shielding efficiency. Each ring unit of the overlapping ring grid with a random structure has different diameters and different periods, which in principle improves the problem of concentrated distribution of high-order diffraction energy of the grid.

Description of drawings

Fig. 1 is a structural schematic diagram of a metal grid with a random overlapping ring structure according to the present invention.

Fig. 2 is a schematic diagram of a random method of diameter 2 R of the metal mesh grid with a random overlapping ring structure according to the present invention.

Fig. 3 is a schematic diagram of the random method of the period g (the random area is a circle) of the randomly overlapping ring-structure metal grid according to the present invention.

Fig. 4 is a schematic diagram of the random method of the period g (the random area is a quadrilateral) of the randomly overlapping ring-structure metal grid according to the present invention.

Fig. 5 is a schematic diagram of a random method for the period g (the random area is a hexagon) of the metal mesh grid with a random overlapping ring structure according to the present invention.

Fig. 6 is a schematic diagram of the grid structure after the period g and the diameter 2 R of the random overlapping ring structure metal grid according to the present invention are randomized.

Detailed ways

The technical solutions in the embodiments of the present invention will be described in detail below in conjunction with the drawings in the embodiments of the present invention.

Example 1:

In this embodiment, the random region of the period g of the randomly overlapping ring grid is a circular region, and the initial parameters of the overlapping ring grid of the periodic structure are period g ₀ =400 μm and diameter 2 R ₀ =600 μm. The random range of the period g of the grid is designed to be 35%, and the random range of the diameter 2 R is designed to be 35%. A circular area with a radius of r is generated at the center of each ring unit. This circular area is concentric with the ring, and a series of uniformly distributed points are generated in the X-axis direction of a small circle with a radius of r , and randomly distributed in the X direction. Select a point, and select a y coordinate in the Y direction corresponding to this x coordinate, ( x , y ) is the position of the center of the circle after randomization, and the random range of period g is [ g ₀ -2 r , g ₀ - 2r ]. The ring diameter is randomized within [2 R ₀ -Δ R ,2 R ₀ +Δ R ]. By adjusting the value of r to change the size of the period g random region, by adjusting the size of Δ R , to change the random range of diameter 2 R.

Example 2:

In this embodiment, the random region of the period g of the randomly overlapping circular ring grid is a square region, and the initial parameters of the periodic overlapping circular ring grid are period g ₀ =400 μm and diameter 2 R ₀ =600 μm. A square area with side length a is generated at the center of each ring. The center of the square area coincides with the center of the ring. Randomly select a point in the X-axis direction of the square, and in the Y-axis direction corresponding to this x coordinate. Select a y coordinate, ( x , y ) is the center position of the ring after randomization, and the random range of period g is [ g ₀ - a ,( g ₀ ² +2 a ² +2 g ₀ a ) ^1/2 ] . By adjusting the value of the side length a to change the size of the period g random area, by adjusting the size of Δ R , to change the random range of the diameter 2 R.

Example 3:

In this embodiment, the random region of the period g of the randomly overlapping ring grid is a hexagonal region, and the initial parameters of the overlapping ring grid of the periodic structure are period g ₀ =400 μm, diameter 2 R ₀ =600 μm. A regular hexagonal area with side length b is generated at the center of each ring. The center of the regular hexagon coincides with the center of the ring. Select a random point in the X-axis direction of the regular hexagon and correspond to the x coordinate. Select a y- coordinate in the Y-axis direction of , ( x , y ) is the center position of the ring after randomization, and the random range of g is [ g ₀ -1.732 b ,( g ₀ ² +4 b ² +3.464 bg ₀ ) ^{1 /2} ], change the random range of diameter 2 R by adjusting the size of Δ R .

Claims (7)

1. It is 1. a kind of based on center location annulus grid design method overlapping with variable diameters at random, it is characterised in that the grid is by justifying Ring element form, periodic array arrangement overlapping annulus grid on the basis of be randomized, grid can random parameter packet Include diameter 2RWith the periodg。
2. 2. it is according to claim 1 based on center location annulus grid design method overlapping with variable diameters at random, it is special Sign is, includes the following steps：

   （1）Annulus unit is arranged with 60 ° of periodic arrays, it is mutually overlapping between adjacent rings；

   （2）The fixed-size region centered on the center of circle is generated in the center location of each annulus；

   （3）Generate a random point in the fixed area of each circle ring center, it is as random after center location；

   （4）By each diameter of a circle parameter 2RIn initial diameter parameter 2R ₀Symmetrical range [2R ₀-ΔR,2R ₀+ΔR] in carry out Randomization.
3. 3. the diameter parameters according to claim 1 based on overlapping annulus grid are joined with the period with round random areas Several random device, it is characterised in that the period of gridgWith diameter 2RRatiog/2RMore than 1.
4. 4. it is according to claim 1 based on center location annulus grid design method overlapping with variable diameters at random, it is special Sign is that the random fashion of grid is random period simultaneouslygWith diameter 2RParameter.
5. 5. it is according to claim 1 based on center location annulus grid design method overlapping with variable diameters at random, it is special Sign is the periodgRandom range can be adjusted by changing the size of fixed area, the range of fixed area need to be less than annulus The regional extent of unit.
6. 6. it is according to claim 1 based on center location annulus grid design method overlapping with variable diameters at random, it is special Sign is, in step 1, the fixed area is polygonal regions and the circles such as quadrangle, hexagon.
7. 7. it is according to claim 1 based on center location annulus grid design method overlapping with variable diameters at random, it is special Sign is the periodgWith diameter 2RRandom fashion to be uniformly distributed.