a thickness << incident source wavelength (ideal)

material of rectangular hole is PEC

incident source wavelength : 300 nm

incident source polarization : linear polarization

rectangular hole : 1200 nm x 1200 nm

Results :

Define Parameters

A.Main-Setup

1. Define total x, y, z length that equal to CAD, and then set a appropriate resolution.

2. Press【建立網格 Cad to Grids (Create)】button to create simulation grids.

set a appropriate simulation size, here are 2000 nm x 2000 nm x 500 nm

B.Boundary Conditions

A. Define the boundary conditions

B. Press the【創建 (Create)】button => Create the total grid size (Include the boundary condition & add space)

C.Wave & Observation

The incident wave is linear polarization in x-y axis (pis=0) from bottom side(theta =0).

D. Probe & Lumped

None, press 【創建(Create)】 button

E. Geometries. Design

Checked out the simulation geometries, and then press 【輸出 Output】button to output the geometries files

Data_Materials.csv // (simulation index of structures)

In this example the "矩形孔洞 Square Hole" structure is using the built-in function.

instruction webpage: Built-in Function

%======矩形孔洞 SquareHole=======

lengthx=1200e-9;

lengthy=1200e-9;

lengthz=20e-9;

nindex=1^2;

sigma=0;

choice='PEC'; %E_Iso,PEC,M_Iso,PMC,E_Model1,M_Model1,EM_Model1

gridtype=-1;    %

xposition=icenter*gdx;

yposition=icenter*gdy;

zposition=kcenter*gdz;

Iso_SquareHole(choice,gridtype,nindex,sigma,xposition,yposition,zposition,lengthx,lengthy,lengthz)

%==========矩形孔洞 SquareHole==========

F.Spectrum & Field Pattern

1. Set the Spectrum Analysis & Wavelength range

2. Check out the source

In this example the source wavelength =300 nm

G.Calculation

1. Set the simulation time setp

2. Save parameters

3. Calculation

H.Result Analysis

★(Result Analysis)：

(1) Press 【快速載入結果 Fast load results】button

(2) Select : 穩態場分析 (Steady State Field Pattern Analysis)

and then select (All-Fileds)

define Near To Far-Field Transformation direction & range

(1) check the observe direction, in this example, the incident source from bottom. The observation range here set the area at top side

Z+ direction

(2) Press the 【計算 Calculate】button

(3) Press the 【畫圖 Plot】button

The plot unit have three kinds

1. dB log(

2. Linear

3. Sqrt

Filed plot have four kinds expression

Here are the simulation results of single rectangular PEC hole

Compare the simulation and Analytical solution

After calculation, input the following MATLAB code in 【指令區塊中 Command Panel】

a, b = 4 in analytical solution means the ratio of rectangular hole / incident wavelength

In FonSinEM simulation, the hole size = 1200 nm x 1200 nm, the incident wavelength = 300 nm

%----- Analytical Solution -----

figure(2);hold on;

a = 4; b = 4;

[theta,phi] = meshgrid(-90:1:90, 0:1:360);

theta = theta*pi/180; phi = phi*pi/180;

vx = a*sin(theta).*cos(phi);

vy = b*sin(theta).*sin(phi);

E = abs((1 + cos(theta))/2 .* sinc(vx) .* sinc(vy));

surf(vx/a,vy/b,(E));

shading interp; 

colormap(jet)

set(gca, 'color', 'none');

set(gcf, 'InvertHardCopy', 'off');

%----- FonSinEM -----

a_theta=(theta_start:theta_span:theta_end)*pi/180;

a_phi=(phi_start:phi_span:phi_end)*pi/180;

[b_theta,b_phi]=meshgrid(a_theta,a_phi);

figure(2)

vx=sin(b_theta).*cos(b_phi);

vy=sin(b_theta).*sin(b_phi);

plot3(vx,vy,RCS_Far'/max(RCS_Far(:)));shading interp;xlabel('X');ylabel('Y');

view(-30,10)=====