def demo_2():
"""
Polarisation camera CIS instrument
"""
# FLIR BLACKFLY POLARISATION CAMERA
bit_depth = 12
sensor_dim = (2048, 2448)
pix_size = 3.45e-6
qe = 0.35
epercount = 0.46 # [e / count]
cam_noise = 2.5
cam = pycis.PolCamera(bit_depth, sensor_dim, pix_size, qe, epercount,
cam_noise)
# cam = pycis.Camera(bit_depth, sensor_dim, pix_size, qe, epercount, cam_noise)
# define imaging lens
flength = 85e-3
backlens = pycis.Lens(flength)
# define interferometer components
wp2 = pycis.UniaxialCrystal(np.pi / 4, 4.48e-3, 0, contrast=0.45)
qwp = pycis.QuarterWaveplate(0)
pol1 = pycis.LinearPolariser(0)
pol2 = pycis.LinearPolariser(0)
wp1 = pycis.UniaxialCrystal(np.pi / 4, 9.8e-3, 0, contrast=0.6)
sp1 = pycis.SavartPlate(np.pi / 4, 6.2e-3)
# first component in interferometer list is the first component that the light passes through
interferometer = [pol1, sp1, wp1, pol2, wp2, qwp]
# interferometer = [pol2, wp2, qwp]
# interferometer = [pol1, sp1, wp1, pol2]
# bringing it together into an instrument
inst = pycis.Instrument(cam, backlens, interferometer)
wl = 466e-9 # [ m ]
spec = 1e4 # [ photons / pixel / time step ]
s = time.time()
si = pycis.SynthImage(inst, wl, spec)
e = time.time()
print(e - s, ' seconds')
pycis.fourier_demod_doubledelay(si.igram, nfringes=62)
# dc_1, phase_1, contrast_1 = pycis.fourier_demod_doubledelay(si.igram, display=True, nfringes=62)
# dc_2, phase_2, contrast_2 = pycis.polcam_demod(dc_1)
# pycis.fourier_demod_2d(I0, display=True)
# I02, phi2, contrast2 = pycis.polcam_demod2(si.igram)
plt.figure()
plt.imshow(si.igram, 'gray')
plt.colorbar()
def demo_testing_demodulation():
# define camera
# pco.edge 5.5 camera
bit_depth = 16
# sensor_dim = (2560, 2160)
sensor_dim = (1000, 1000)
pix_size = 6.5e-6
qe = 0.35
epercount = 0.46 # [e / count]
cam_noise = 2.5
cam = pycis.PolCamera(bit_depth, sensor_dim, pix_size, qe, epercount,
cam_noise)
# define imaging lens
flength = 85e-3
backlens = pycis.Lens(flength)
# list interferometer components
pol_1 = pycis.LinearPolariser(0)
wp_1 = pycis.UniaxialCrystal(np.pi / 4, 40e-3, 0)
qwp = pycis.QuarterWaveplate(0)
# first component in interferometer list is the first component that the light passes through
interferometer = [pol_1, wp_1, qwp]
# bringing it together into an instrument
inst = pycis.Instrument(cam, backlens, interferometer)
# wl = 466e-9
# spec = 1e5
wl = 464.9e-9
spec = 1e5
s = time.time()
si = pycis.SynthImage(inst, wl, spec)
e = time.time()
print(e - s, ' seconds')
# DEMODULATION
img = si.igram
# make low pass filter
dy, dx = img.shape
lpfilt_y = np.pad(scipy.signal.tukey(int(0.98 * dy), alpha=0.25),
(int(0.01 * dy), int(0.01 * dy)), 'constant')
lpfilt_x = np.pad(scipy.signal.tukey(int(0.98 * dx), alpha=0.25),
(int(0.01 * dx), int(0.01 * dx)), 'constant')
lpfilt_yy = np.tile(lpfilt_y, (dx, 1)).T
lpfilt_xx = np.tile(lpfilt_x, (dy, 1))
lpfilt = lpfilt_xx * lpfilt_yy
dc = np.real(
np.fft.ifft2(
np.fft.ifftshift(np.fft.fftshift(np.fft.fft2(img)) * lpfilt)))
plt.figure()
plt.imshow(dc)
plt.colorbar()
fig_p = plt.figure()
ax_p = fig_p.add_subplot(111)
imp = ax_p.imshow(pycis.wrap(-inst.calculate_ideal_phase_delay(wl)))
fig_p.colorbar(imp, ax=ax_p)
ref_ph = np.zeros_like(img, dtype=np.complex)
ref_ph[::2, ::2] = 2 * 3 * np.pi / 4
ref_ph[::2, 1::2] = 2 * np.pi / 2
ref_ph[1::2, ::2] = 2 * 0
ref_ph[1::2, 1::2] = 2 * np.pi / 4
ref = np.exp(1j * ref_ph)
img_ref = img.astype(float) * ref
ft_img_ref = np.fft.fft2(img_ref)
img_ref_lp = np.fft.ifft2(
np.fft.ifftshift(np.fft.fftshift(ft_img_ref) * lpfilt))
si.img_igram()
si.img_fft()
plt.figure()
plt.imshow(-np.angle(img_ref_lp))
plt.colorbar()
plt.figure()
plt.imshow(2 * np.abs(img_ref_lp) / dc)
plt.colorbar()
plt.figure()
plt.imshow(lpfilt)
plt.colorbar()
plt.show()
return
def demo_multi_delay():
"""
multi-delay CIS instrument
:return:
"""
# define camera
# pco.edge 5.5 camera
bit_depth = 16
# sensor_dim = (2560, 2160)
sensor_dim = (1000, 1000)
pix_size = 6.5e-6
qe = 0.35
epercount = 0.46 # [e / count]
cam_noise = 2.5
cam = pycis.Camera(bit_depth, sensor_dim, pix_size, qe, epercount,
cam_noise)
# define imaging lens
flength = 50e-3
backlens = pycis.Lens(flength)
# list interferometer components
pol_1 = pycis.LinearPolariser(np.pi / 4)
sp_1 = pycis.SavartPlate(np.pi / 4, 15e-3)
dp_1 = pycis.UniaxialCrystal(np.pi / 2, 2e-3, np.pi / 4, contrast=0.9)
pol_2 = pycis.LinearPolariser(np.pi / 4)
# wp_2 = pycis.UniaxialCrystal(-np.pi / 4, 9e-3, np.pi / 8, contrast=0.9)
# pol_3 = pycis.LinearPolariser(0)
# first component in interferometer list is the first component that the light passes through
interferometer = [pol_1, sp_1, dp_1, pol_2] # , wp_2, pol_3]
# bringing it together into an instrument
inst = pycis.Instrument(cam, backlens, interferometer)
wl = 466e-9
spec = 1e5
# wl0 = 464.9e-9
# std = 0.090e-9
# wl = np.linspace(wl0 - 3 * std, wl0 + 3 * std, 21)
#
# generate spectrum
# spec = 1 / np.sqrt(2 * np.pi * std ** 2) * np.exp(-1 / 2 * ((wl - wl0) / std) ** 2) * 1e5
# pad speectrum to sensor array dimensions
# spec = np.tile(spec[:, np.newaxis, np.newaxis], [1, sensor_dim[0], sensor_dim[1]])
# stokes parameters
# a0 = np.zeros_like(spec)
# spec = np.array([spec, a0, a0, a0])
s = time.time()
si = pycis.SynthImage(inst, wl, spec)
e = time.time()
print(e - s, ' seconds')
si.img_igram()
si.img_fft()
plt.show()
def demo_pol_or():
"""
Polarisation camera CIS instrument
"""
# FLIR BLACKFLY POLARISATION CAMERA
bit_depth = 12
# sensor_dim = (2048, 2448)
sensor_dim = (348, 348)
pix_size = 3.45e-6
qe = 0.35
epercount = 0.46 # [e / count]
cam_noise = 0.
cam = pycis.PolCamera(bit_depth, sensor_dim, pix_size, qe, epercount,
cam_noise)
# define imaging lens
flength = 5e-3
backlens = pycis.Lens(flength)
# define interferometer components
wp = pycis.UniaxialCrystal(-np.pi / 4, 4 * 1e-3, 0)
qwp = pycis.QuarterWaveplate(np.pi / 2)
pol_1 = pycis.LinearPolariser(np.pi / 2)
# first component in interferometer list is the first component that the light passes through
interferometer = [pol_1, wp, qwp]
# bringing it together into an instrument
inst = pycis.Instrument(cam, backlens, interferometer)
# generate spectrum
wl0 = 464.9e-9
std = 1 / 2 * 0.090e-9
wl = np.linspace(wl0 - 5 * std, wl0 + 5 * std, 50)
i0_in = 5e2
spec = 1 / np.sqrt(2 * np.pi * std**2) * np.exp(-1 / 2 * (
(wl - wl0) / std)**2) * i0_in
# pad spectrum to sensor array dimensions
spec = np.tile(spec[:, np.newaxis, np.newaxis],
[1, sensor_dim[0], sensor_dim[1]])
s = time.time()
si = pycis.SynthImage(inst, wl, spec)
e = time.time()
print(e - s, ' seconds')
img = si.igram
i3 = img[::2, ::2]
i2 = img[1::2, ::2]
i4 = img[::2, 1::2]
i1 = img[1::2, 1::2]
i0 = i3 + i2 + i4 + i1
phase = np.arctan2(i4 - i2, i3 - i1)
contrast = 1 / i0 * np.sqrt(8 * ((i3 - i0 / 4)**2 + (i2 - i0 / 4)**2 +
(i1 - i0 / 4)**2 + (i4 - i0 / 4)**2))
phase0 = inst.calculate_ideal_phase_offset(wl0)
doc_ideal = pycis.measure_degree_coherence(spec[:, 0, 0],
wl,
phase0,
material=None)
doc_disp = pycis.measure_degree_coherence(spec[:, 0, 0],
wl,
phase0,
material='a-BBO')
print(phase0)
print(doc_ideal, abs(doc_ideal) / i0_in, np.angle(doc_ideal))
print(doc_disp, abs(doc_disp) / i0_in, np.angle(doc_disp))
# ref_ph = np.zeros_like(img)
# ref_ph[::2, ::2] = 2 * np.pi / 2
# ref_ph[1::2, ::2] = 2 * np.pi / 4
# ref_ph[::2, 1::2] = 2 * 3 * np.pi / 4
# ref_ph[1::2, 1::2] = 2 * 0
# ref = np.exp(1j * ref_ph)
# img_ref = img * ref
# img_fft = np.fft.fftshift(np.fft.fft2(img))
# img_ref_fft = np.fft.fftshift(np.fft.fft2(img_ref))
fig = plt.figure()
gs2 = matplotlib.gridspec.GridSpec(nrows=2, ncols=2)
ax1 = fig.add_subplot(gs2[0])
ax2 = fig.add_subplot(gs2[1])
ax3 = fig.add_subplot(gs2[2])
ax4 = fig.add_subplot(gs2[3])
ax1.imshow(img)
ax2.imshow(phase)
ax3.imshow(contrast)
ax4.imshow(i0)
print(np.mean(contrast))
plt.show()