gaussian_size = 1.00 / sqrt(
2) * mm # 1/e Intensity width of beam; (note, it's not the 1/e^2)
step_size = 5. * mm # LPForvard step size
f = 20 * cm # focal length of SLM lens
l = 8 # azimuthal order of LG beam
p = 1
omega0_p = .5
######## END Param ##############
####### Create LG order
dx = (2 / (N - 1.))
x = y = 3 * r_[-1:(1 + dx):dx]
[xx, yy] = meshgrid(x, y)
lg = lg.LG_xy( l=l, p=0, xx=xx, yy=yy, omega0=2/sqrt(l) ) \
+ lg.LG_xy( l=0, p=p, xx=xx, yy=yy, omega0=.85*2/sqrt(l) )
# normalize lg; we only want the phase information
lg /= abs(lg)
#imshow (angle(lg)); show()
####### END Create LG order
propagate = Propagate(vmin=0., vmax=100.)
F = Field(N, side_length, wavelength)
F.gaussian_aperture(gaussian_size)
#F.lens(f)
F.value[:] *= lg
#propagate(F, z=2*f, dz=.5*cm)
wavelength = 780 * nm # Wavelength
gaussian_size = 1.00 / sqrt(
2) * mm # 1/e Intensity width of beam; (note, it's not the 1/e^2)
axicon_angle = 175 / 180. * pi # included angle of SLM
axicon_n1 = 1.5 # index of refraction of the axicon
step_size = 5. * mm # LPForvard step size
l = 2 # azimuthal order of LG beam
######## END Param ##############
####### Create LG order
dx = (2 / (N - 1.))
x = y = 3 * r_[-1:(1 + dx):dx]
[xx, yy] = meshgrid(x, y)
lg = lg.LG_xy(l=l, p=0, xx=xx, yy=yy, omega0=2 / sqrt(l))
# normalize lg; we only want the phase information
lg /= abs(lg)
#imshow (x,y,arg(lg))
####### END Create LG order
propagate = Propagate()
F = Field(N, side_length, wavelength)
F.gaussian_aperture(gaussian_size)
F.axicon(axicon_angle, axicon_n1)
#F4 = propagate(13.*cm, step_size, F3,0,0,4);
F.forvard(7.5 * cm)
F.axicon(axicon_angle, axicon_n1)
print 'moving towards slm'
dx = 2 * d * sin(a) # displacement of secondary beam parallel to glass.
dx0 = dx * cos(a0) # displacement of secondary beam transverse to output beam.
l = 8 # azimuthal order of LG beam
P = 250 * mW # beam power
######## END Param ##############
####### Create LG order
dx = (2 / (N - 1.))
x = y = (side_length / 2) * r_[-1:(1 + dx):dx]
[xx, yy] = meshgrid(x, y)
lg = lg.LG_xy(l=l,
p=0,
xx=xx * 6 / side_length,
yy=yy * 6 / side_length,
omega0=2 / sqrt(l))
# normalize lg; we only want the phase information
lg /= abs(lg)
#imshow (x,y,angle(lg))
####### END Create LG order
propagate = Propagate()
F = Field(N, side_length, wavelength)
F.gaussian_aperture(gaussian_size)
Pf = P / sum(F.value * F.value.conj()) # power per grid cell [ W ]
Ef = sqrt(Pf / grid_dx**2) # sqrt(I) [ sqrt(W/m^2) ]
Ef /= sqrt(mW / cm**2) # put Ef in units [ sqrt(mW/cm^2) ]