tmp_optifik/optifik/scheludko.py
François Boulogne d5fae56eb4 formattage
2025-05-27 16:21:16 +02:00

321 lines
9.4 KiB
Python

import numpy as np
from scipy.optimize import curve_fit
import matplotlib.pyplot as plt
plt.rc('text', usetex=True)
plt.rcParams.update({
'axes.labelsize': 26,
'xtick.labelsize': 32,
'ytick.labelsize': 32,
'legend.fontsize': 23,
})
from .io import load_spectrum
from .utils import OptimizeResult
from .analysis import finds_peak
def thickness_scheludko_at_order(wavelengths,
intensities,
interference_order,
refractive_index,
Imin=None):
"""
Compute the film thickness for a given interference order.
Parameters
----------
wavelengths : array
Wavelength values in nm.
intensities : array
Intensity values.
interference_order: TYPE
DESCRIPTION.
refractive_index : TYPE
DESCRIPTION.
Imin : TYPE, optional
DESCRIPTION. The default is None.
Returns
-------
thickness : TYPE
DESCRIPTION.
"""
if Imin is None:
Imin = np.min(intensities)
n = refractive_index
m = interference_order
I = (np.asarray(intensities) - Imin) / (np.max(intensities) - Imin)
prefactor = wavelengths / (2 * np.pi * n)
argument = np.sqrt(I / (1 + (1 - I) * (n**2 - 1)**2 / (4 * n**2)))
if m % 2 == 0:
term1 = (m / 2) * np.pi
else:
term1 = ((m+1) / 2) * np.pi
term2 = (-1)**m * np.arcsin(argument)
return prefactor * (term1 + term2)
def Delta(wavelengths, thickness, interference_order, refractive_index):
"""
Compute the Delta values.
Parameters
----------
wavelengths : array
Wavelength values in nm.
thickness : array_like (or float)
Film thickness.
interference_order : int
Interference order.
refractive_index : array_like (or float)
Refractive index.
Returns
-------
ndarray
Delta values.
"""
# ensure that the entries are numpy arrays
wavelengths = np.asarray(wavelengths)
h = np.asarray(thickness)
n = np.asarray(refractive_index)
m = interference_order
# Calculation of p as a function of the parity of m
if m % 2 == 0:
p = m / 2
else:
p = (m + 1) / 2
# Calculation of alpha
alpha = ((n**2 - 1)**2) / (4 * n**2)
# Argument of sinus
angle = (2 * np.pi * n * h / wavelengths) - p * np.pi
# A = sin²(argument)
A = np.sin(angle)**2
# Final calcuation of Delta
return (A * (1 + alpha)) / (1 + A * alpha)
def Delta_fit(xdata, thickness, interference_order):
"""
Wrapper on Delta() for curve_fit.
Parameters
----------
xdata : tuple
(wavelengths, refractive_index)
thickness : array_like (or float)
Film thickness.
interference_order : int
Interference order.
Returns
-------
ndarray
Delta values.
"""
lambdas, r_index = xdata
return Delta(lambdas, thickness, interference_order, r_index)
def thickness_from_scheludko(wavelengths,
intensities,
refractive_index,
min_peak_prominence,
plot=None):
"""
Parameters
----------
wavelengths : array
Wavelength values in nm.
intensities : array
Intensity values.
refractive_index : scalar, optional
Value of the refractive index of the medium.
plot : bool, optional
Display a curve, useful for checking or debuging. The default is None.
Returns
-------
thickness : TYPE
DESCRIPTION.
"""
max_tested_order = 12
r_index = refractive_index
peaks_min, peaks_max = finds_peak(wavelengths, intensities,
min_peak_prominence=min_peak_prominence,
plot=False)
# Get the last oscillation peaks
lambda_min = wavelengths[peaks_min[-1]]
lambda_max = wavelengths[peaks_max[-1]]
# Order them
lambda_start = min(lambda_min, lambda_max)
lambda_stop = max(lambda_min, lambda_max)
# mask input data
mask = (wavelengths >= lambda_start) & (wavelengths <= lambda_stop)
wavelengths_masked = wavelengths[mask]
r_index_masked = r_index[mask]
intensities_masked = intensities[mask]
min_ecart = np.inf
best_m = None
best_h = None
if plot:
plt.figure(figsize=(10, 6), dpi=300)
plt.ylabel(r'$h$ ($\mathrm{{nm}}$)')
plt.xlabel(r'$\lambda$ ($ \mathrm{nm} $)')
for m in range(0, max_tested_order+1):
h_values = thickness_scheludko_at_order(wavelengths_masked,
intensities_masked,
m, r_index_masked)
ecart = np.max(h_values) - np.min(h_values)
print(f"Écart pour m={m} : {ecart:.3f} nm")
if ecart < min_ecart:
min_ecart = ecart
best_m = m
best_h = h_values
if plot:
plt.plot(wavelengths_masked, h_values,'.', markersize=3, label=f"Épaisseur du film (Scheludko, m={m})")
# Delta
num = intensities_masked - np.min(intensities_masked)
denom = np.max(intensities_masked) - np.min(intensities_masked)
DeltaVrai = num / denom
# DeltaVrai = (intensities_masked -np.min(intensities_masked))/(np.max(intensities_masked) -np.min(intensities_masked))
# DeltaVrai = (intensities_raw_masked -np.min(intensities_raw_masked))/(np.max(intensities_raw_masked) -np.min(intensities_raw_masked))
DeltaScheludko = Delta(wavelengths_masked,
np.mean(best_h),
best_m,
r_index_masked)
xdata = (wavelengths_masked, r_index_masked)
popt, pcov = curve_fit(lambda x, h: Delta_fit(x, h, m), xdata, DeltaVrai, p0=[np.mean(best_h)])
fitted_h = popt[0]
if plot:
Delta_values = Delta(wavelengths_masked, fitted_h, best_m, r_index_masked)
plt.figure(figsize=(10, 6), dpi=300)
plt.plot(wavelengths_masked, DeltaVrai,
'bo-', markersize=2, label=r'$\mathrm{{Smoothed}}\ \mathrm{{Data}}$')
plt.plot(wavelengths_masked, DeltaScheludko,
'go-', markersize=2, label = rf'$\mathrm{{Scheludko}}\ (h = {np.mean(best_h):.1f} \pm {np.std(best_h):.1f}\ \mathrm{{nm}})$')
plt.plot(wavelengths_masked, Delta_values, 'ro-',markersize=2, label=rf'$\mathrm{{Fit}}\ (h = {fitted_h:.1f}\pm {np.sqrt(pcov[0][0]):.1f} \ \mathrm{{nm}})$')
plt.legend()
plt.ylabel(r'$\Delta$')
plt.xlabel(r'$\lambda$ ($ \mathrm{nm} $)')
return OptimizeResult(thickness=fitted_h ,)
def thickness_for_order0(wavelengths,
intensities,
refractive_index,
min_peak_prominence,
plot=None):
# TODO :
# Load "trou"
File_I_min = 'tests/spectre_trou/000043641.xy'
wavelengths_I_min, intensities_I_min = load_spectrum(File_I_min, lambda_min=450)
r_index = refractive_index
peaks_min, peaks_max = finds_peak(wavelengths, intensities,
min_peak_prominence=min_peak_prominence,
plot=False)
lambda_unique = wavelengths[peaks_max[0]]
# On crée le masque pour ne garder que les wavelengths superieures a wavelengths unique
mask = wavelengths >= lambda_unique
wavelengths_masked = wavelengths[mask]
r_index_masked = r_index[mask]
intensities_masked = intensities[mask]
intensities_I_min_masked =intensities_I_min[mask]
# best_m = None
# best_h = None
m = 0
h_values = thickness_scheludko_at_order(wavelengths_masked,
intensities_masked,
0,
r_index_masked,
Imin=intensities_I_min_masked)
if plot:
plt.figure(figsize=(10, 6), dpi=300)
plt.plot(wavelengths_masked, h_values, label=r"Épaisseur du film (Scheludko, m=0)")
best_m = m
best_h = h_values
# Delta
num = intensities_masked - np.min(intensities_I_min_masked)
denom = np.max(intensities_masked) - np.min(intensities_I_min_masked)
DeltaVrai = num / denom
DeltaScheludko = Delta(wavelengths_masked, np.mean(best_h), best_m, r_index_masked)
#print(np.mean(best_h),np.std(best_h))
if plot:
plt.figure(figsize=(10, 6), dpi=300)
plt.plot(wavelengths_masked,DeltaVrai,'bo-', markersize=2,label=r'$\mathrm{{Raw}}\ \mathrm{{Data}}$')
plt.plot(wavelengths_masked,DeltaScheludko,'ro-', markersize=2,label = rf'$\mathrm{{Scheludko}}\ (h = {np.mean(best_h):.1f} \pm {np.std(best_h):.1f}\ \mathrm{{nm}})$')
xdata = (wavelengths_masked, r_index_masked)
popt, pcov = curve_fit(lambda x, h: Delta_fit(x, h, m), xdata, DeltaVrai, p0=[np.mean(best_h)])
fitted_h = popt[0]
if plot:
Delta_values = Delta(wavelengths_masked, fitted_h, best_m, r_index_masked)
plt.plot(wavelengths_masked, Delta_values,
'go-', markersize=2,
label=rf'$\mathrm{{Fit}}\ (h = {fitted_h:.1f}\pm {np.sqrt(pcov[0][0]):.1f} \ \mathrm{{nm}})$')
plt.legend()
plt.ylabel(r'$\Delta$')
plt.xlabel(r'$\lambda$ (nm)')
return OptimizeResult(thickness=fitted_h,)