def modelSourceVolume():
"""Model source volume
Source volume model of the laboratory situation described in
Refs. [1,2].
Args:
None
Returns:
(x,y,z) (3-tuple, numpy array, ndim=1): 1D coordinate grids.
(x0,y0,z0) (2-tuple, floats): x and y center position of ISP
symmetry axis and z position of absorbing layer.
roi (numpy array, ndim=3): computational region of interest
containing absorbed energy density in units (J/m^3).
Note:
Used units are: mu (cm^-1) and F0 (J/cm^2), hence after beam
propagation one yields roi (J/cm^3 = 10^6 J/m^3). Output is
adjusted to roi in units (J/m^3).
The parameters used for the flat-top beam profile and the
irradiated fluence are taken from Ref. [2].
Refs:
[1] Light distribution measurement sin absorbing materials by
optical detection of laser-induced stress waves
Paltauf, G and Schmidt-Kloiber, H and Guss, H
Appl. Phys. Lett. 69 (1996) 1526
[2] Measurement of laser-induced acoustic waves with a calibrated
optical transducer
Paltauf, G and Schmidt-Kloiber, H
J. Appl. Phys. 82 (1997) 1525
"""
# SOURCE VOLUME PARS --------------------------------------------------
xMax, Nx = 0.6, 600 # bdry, meshpts: x-axis
yMax, Ny = 0.6, 600 # bdry, meshpts: y-axis
zMax, Nz = 0.6, 200 # bdry, meshpts: z-axis
# ABSORBING LAYER PARS ------------------------------------------------
z0, dz = 0.0, 0.6 # start, width of absorbing layer
mu = 24.0 # absorption coeffiecient
# FLAT TOP BEAM PROFILE PARS -----------------------------------------
x0, y0 = xMax / 2, yMax / 2 # x,y pos of symmetry axis
fta, ftr = float(sys.argv[1]), 4.5 # radius, radius/edge width ratio
f0 = 0.18 # incident fluence (J/cm^2)
# SET OPTICAL PROPERTIES OF SOURCE VOLUME -----------------------------
(x, y, z), roi = sv.setROI((xMax, yMax, zMax), (Nx, Ny, Nz))
sv.addAbsorbingLayer(((x, y, z), roi), z0, dz, mu)
# CHOOSE ISP AND PROPAGATE BEAM ---------------------------------------
iProf = f0 * isp.flatTop((x, y), (x0, y0), fta, ftr)
sv.propagateBeam((z, roi), iProf)
# roi in units (J/cm^3 = 10^6 J/m^3). Scale output to (J/m^3).
return (x, y, z), (x0, y0, z0), roi * 10**6
def modelSourceVolume():
"""Model source volume
Source volume model of the laboratory situation underlying Figs. 8(a,b)
in Ref. [1], Section IV.B on far field measurements.
Args:
ma (float): absorption coefficient in (cm^-1).
ftd (float): diameter of flat-top ISP in (cm)
Returns:
(x,y,z) (3-tuple, numpy array, ndim=1): 1D coordinate grids.
(x0,y0,z0) (2-tuple, floats): x and y center position of ISP
symmetry axis and z position of absorbing layer.
roi (numpy array, ndim=3): computational region of interest
containing absorbed energy density in units (J/m^3).
Note:
Used units are: mu (cm^-1) and F0 (J/cm^2), hence after beam
propagation one yields roi (J/cm^3 = 10^6 J/m^3). Output is
adjusted to roi in units (J/m^3).
The parameters used for the flat-top beam profile and the
irradiated fluence are adjusted to reproduce the experimental
data displayed in Fig. 8 of Ref. [1].
Refs:
[1] Pulsed optoacoustic characterization of layered media
Paltauf, G and Schmidt-Kloiber, H
J. Appl. Phys. 88 (2000) 1624
"""
# SOURCE VOLUME PARS --------------------------------------------------
#xMax, Nx = 1.0, 900 # bdry, meshpts: x-axis
#yMax, Ny = 1.0, 900 # bdry, meshpts: y-axis
#zMax, Nz = 1.0, 300 # bdry, meshpts: z-axis
xMax, Nx = 1.0, 900 # bdry, meshpts: x-axis
yMax, Ny = 1.0, 900 # bdry, meshpts: y-axis
zMax, Nz = 1.0, 263 # bdry, meshpts: z-axis
# ABSORBING LAYER PARS ------------------------------------------------
z0, dz = 0.0, 1.0 # start, width of absorbing layer
# FLAT TOP BEAM PROFILE PARS -----------------------------------------
x0, y0 = xMax / 2, yMax / 2 # x,y pos of symmetry axis
fta, ftR = 0.1, 2. # radius, edge width
f0 = 1.0 # incident fluence (J/cm^2)
# SET OPTICAL PROPERTIES OF SOURCE VOLUME -----------------------------
ma = 24.0 # absorption coeficcient
(x, y, z), roi = sv.setROI((xMax, yMax, zMax), (Nx, Ny, Nz))
sv.addAbsorbingLayer(((x, y, z), roi), z0, dz, ma)
# CHOOSE ISP AND PROPAGATE BEAM ---------------------------------------
iProf = f0 * isp.flatTop((x, y), (x0, y0), fta, ftR)
sv.propagateBeam((z, roi), iProf)
# roi in units (J/cm^3 = 10^6 J/m^3). Scale output to (J/m^3).
return (x, y, z), (x0, y0, z0), roi * 10**6
