Gaussian beam Propagation about lightpipes HOT 2 CLOSED

import matplotlib.pyplot as plt
import numpy as np
from LightPipes import *

size=30*mm
labda=500*nm
N=500

w0=1*mm
F=Begin(size,labda,N)
X,Y=F.mgrid_cartesian

F=GaussBeam(F,w0)
z=1000.0*cm
Fz=Fresnel(F,z)
Iz=Intensity(Fz)

#Analytical formulas:
ZR=np.pi*w0*w0/labda #Rayleigh length
w=w0*np.sqrt(1+(z/ZR)**2) #Beam waist at z
Ianalytical=((w0/w)**2)*np.exp(-2*(X/w)**2) + 0.02 #Analytical formula for TEM00 Gauss at z (I added an offset to compare in the plot)

plt.plot(X,Ianalytical,color='red') #analytical result
plt.plot(X,Iz[250],color='blue') #LightPipes result
plt.show()