fresnel diffraction example in main.cc : slit diffraction for fresnel zone

program2D/main.cc

@@ -50,7 +50,10 @@ std::complex<double> loch(double x, double y) {
    if(sqrt(x*x+y*y) < radiusLoch) return 1.0;
    return 0.0;   
 }
-
+std::complex<double> spalt(double x, double y) {
+   if(abs(x) < radiusLoch) return 1.0;
+   return 0.0;
+}
 void CalcFresnel(std::complex<double> (*loch) (double x, double y),
                  double distance,
                  double wavenumber,
@@ -62,9 +65,11 @@ void CalcFresnel(std::complex<double> (*loch) (double x, double y),
 	Y_coordinate2d Y(*blockGridRec);
 
     Function2d2<std::complex<double>,double> Loch(loch);
+    Function2d2<std::complex<double>,double> Spalt(spalt);
     Function2d1<std::complex<double>,double> Expi(expi);
-        
-    varFar = Loch(X,Y) * Expi(wavenumber * (X*X+Y*Y) / (2.0 * distance));
+
+    //varFar = Loch(X,Y) * Expi(wavenumber * (X*X+Y*Y) / (2.0 * distance));
+    varFar = Spalt(X,Y) * Expi(wavenumber * (X*X) / (2.0 * distance));
     varIn  = varFar;
     varFar.FFT();
 }
@@ -73,20 +78,37 @@ void CalcFresnel(std::complex<double> (*loch) (double x, double y),
 int main(int argc, char** argv) {
 	std::ofstream DATEI;
 
-	int n = 9;
+    int n = 10;
 
-    double distance = 20;      //[mm]
+    double distance = 1 ;      //[mm]
     double lambda   = 1.0e-3;  //[mm]
-    radiusLoch = 1;   //[mm]    
-    double geometrySize  =  2; //[mm]
+    radiusLoch = 0.1;   //[mm]
+    double geometrySize  =  0.8; //[mm]
     double wavenumber = 2.0 * M_PI / lambda;
     
-cout << " Test CalcFresnel!!" << endl;    
-    
+    cout << " Test CalcFresnel!!" << endl;
+
+    std::cout << "distance = " << distance << std::endl;
+    std::cout << "lambda = " << lambda << std::endl;
+    std::cout << "aperture = " << radiusLoch << std::endl;
+    std::cout << "geometrySize = " << geometrySize << std::endl;
+
+    std::cout << "Fresnelnumber = " << radiusLoch*radiusLoch / distance / lambda << std::endl;
+    std::cout << "Fresnelnumber >> 1 : near field "      << std::endl;
+    std::cout << "Fresnelnumber ~  1 : fresnel zone"     << std::endl;
+    std::cout << "Fresnelnumber << 1 : fraunhofer zone"  << std::endl;
+
+    double deltaX = geometrySize / pow(2,n-1);
+    double deltaXFourierPlane = lambda * distance / pow(2,n-1) / deltaX;
+    std::cout << "deltaX initial plane (z = 0) = " << deltaX << std::endl;
+    std::cout << "deltaX fourier plane (z = " <<distance<<")  = " << deltaXFourierPlane << std::endl;
+    std::cout << "dxInitial / dxFourier   = " << deltaX / deltaXFourierPlane << std::endl;
+
+
     double radiusGeo = 0.5 * geometrySize;
-    Rectangle geo(-radiusGeo, -radiusGeo, radiusGeo, radiusGeo);   
+    Rechteck geo(-radiusGeo, -radiusGeo, radiusGeo, radiusGeo);
     
-    VariableFFT varE(n,n,geo);    
+    VariableFFT varE(n,n,geo);
     VariableFFT varIn(varE);      
 //    VariableFFT varB(varA);
 /*
@@ -98,12 +120,17 @@ cout << " Test CalcFresnel!!" << endl;
 
     
 
+
+
     
     CalcFresnel(loch,
                  distance,
                  wavenumber,
                  varIn,
                  varE);
+
+    varE = varE / L_infty(  varE);
+
      
 	std::ofstream DATEIA;     
      
@@ -115,13 +142,15 @@ cout << " Test CalcFresnel!!" << endl;
 	varE.Print_VTK(DATEIA);
 	DATEIA.close();
 
-    DATEIA.open("varEimag.vtk");
-	varE.Print_VTK(DATEIA,imPart);
-	DATEIA.close();     
+//    DATEIA.open("varEimag.vtk");
+//	varE.Print_VTK(DATEIA,imPart);
+//	DATEIA.close();
      
-    DATEIA.open("varEreal.vtk");
-	varE.Print_VTK(DATEIA,realPart);
-	DATEIA.close();
+//    DATEIA.open("varEreal.vtk");
+//	varE.Print_VTK(DATEIA,realPart);
+//	DATEIA.close();
+
+    cout << " Test CalcFresnel finished!!" << endl;
 
 }