adding new directory tools

Interferenz/tools/lattice.py

+#!/usr/bin/python3
+"""
+Diffraction and interference at single, double slit and lattice
+
+Usage:
+
+python3 sinc.py
+"""
+import matplotlib.pyplot as plt
+import numpy as np
+
+def lattice(x, b=150., l=200., g=200., N=2):
+    """
+    x: alpha (rad)
+    b: slit width (nm)
+    l: wavelength (nm)
+    g: lattice constant (nm)
+    N: number of illuminated slits
+    """
+    arg = np.pi/l*x
+    ## Spaltfunktion
+    fS  = (np.sin(b*arg)/(b*arg))**2
+    ## Gitterinterferenzfunktion
+    fG  = 1/N/N*(np.sin(N*g*arg)/np.sin(g*arg))**2
+    return fS*fG
+
+# Creating a list of points in x from -10 to 10 to display the functions of 
+# choice
+def plot(b=250., l=200, g=200, N=2):
+    x = np.linspace(-10.2, 10.2, 2000)
+    plt.plot(x, lattice(x=x, b=b, g=g, N=N),
+        color="black", 
+        linestyle="solid",
+        linewidth=1.5, 
+        label=r"Intensität am Gitter"
+        )
+    plt.plot(x, lattice(x=x, b=b, l=l, g=1., N=1),
+        color="black", 
+        linestyle="dashed",
+        linewidth=1., 
+        label=r"Beugung am Spalt"
+        )
+    # Customize the figure
+    plt.xlabel(r'Position (cm)') 
+    plt.ylabel(r'Intensität') 
+    plt.legend(bbox_to_anchor=(0., 1., 1., 0.1), loc="lower left", ncol=2, mode="expand")
+    # Save to pdf
+    plt.savefig("lattice.png")    
+    # Show the plot with a rendering machine
+    #plt.show()
+plot(b=1., l=200., g=120., N=5)
+