wpg.optical_elements module

This module contains definitions of custom optical elements.

Described mapping (or aliases) of some of SRW optical elements (SRWLOpt* <-> wpg)

wpg.optical_elements.Aperture(shape, ap_or_ob, Dx, Dy=1e+23, x=0, y=0)[source]

Defining an aperture/obstacle propagator: A wrapper to a SRWL function SRWLOptA()

Parameters:
  • shape – ‘r’ for rectangular, ‘c’ for circular
  • ap_or_ob – ‘a’ for aperture, ‘o’ for obstacle
  • Dy (Dx,) – transverse dimensions [m]; in case of circular aperture, only Dx is used for diameter
  • y (x,) – transverse coordinates of center [m]
Returns:

opAp - aperture propagator, struct SRWLOptA
wpg.optical_elements.CRL(_foc_plane, _delta, _atten_len, _shape, _apert_h, _apert_v, _r_min, _n, _wall_thick, _xc, _yc, _void_cen_rad=None, _e_start=0, _e_fin=0, _nx=1001, _ny=1001)[source]

Setup Transmission type Optical Element which simulates Compound Refractive Lens (CRL).

Parameters:
  • _foc_plane – plane of focusing: 1- horizontal, 2- vertical, 3- both
  • _delta – refractive index decrement (can be one number of array vs photon energy)
  • _atten_len – attenuation length [m] (can be one number of array vs photon energy)
  • _shape – 1- parabolic, 2- circular (spherical)
  • _apert_h – horizontal aperture size [m]
  • _apert_v – vertical aperture size [m]
  • _r_min – radius (on tip of parabola for parabolic shape) [m]
  • _n – number of lenses (/”holes”)
  • _wall_thick – min. wall thickness between “holes” [m]
  • _xc – horizontal coordinate of center [m]
  • _yc – vertical coordinate of center [m]
  • _void_cen_rad – flat array/list of void center coordinates and radii: [x1, y1, r1, x2, y2, r2,…]
  • _e_start – initial photon energy
  • _e_fin – final photon energy
Returns:

transmission (SRWLOptT) type optical element which simulates CRL
class wpg.optical_elements.Empty[source]

Bases: wpg.optical_elements.WPGOpticalElement

Optical element: Empty. This is empty propagator used for sampling and zooming wavefront

propagate(wfr, propagation_parameters)[source]

Propagate wavefront through empty propagator, used for sampling and resizing wavefront

wpg.optical_elements.Mirror_elliptical(orient, p, q, thetaE, theta0, length, roll=0.0, yaw=0.0, distance=0.0)[source]

Defining a plane elliptical focusing mirror propagator: A wrapper to a SRWL function SRWLOptMirEl()

Parameters:
  • orient – mirror orientation, ‘x’ (horizontal) or ‘y’ (vertical)
  • p – distance to one ellipsis center (source), [m]
  • q – distance to the other ellipsis center (focus), [m]
  • thetaE – design incidence angle in the center of mirror, [rad]
  • theta0 – “real” incidence angle in the center of mirror, [rad]
  • length – mirror length, [m] :param roll: misaligned roll axis :param yaw: misaligned yaw axis
Returns:

opEFM - elliptical mirror propagator, struct SRWLOptMirEl
wpg.optical_elements.Mirror_plane(orient, theta, length, range_xy, filename, scale=1, delim=' ', xscale=1, x0=0.0, bPlot=False)[source]

Defining a plane mirror propagator with taking into account surface height errors

Parameters:
  • orient – mirror orientation, ‘x’ (horizontal) or ‘y’ (vertical)
  • theta – incidence angle [rad]
  • length – mirror length, [m]
  • range_xy – range in which the incident WF defined [m]
  • filename – full file name with mirror profile of two columns, x and h(x) - heigh errors [m]
  • scale –
    • height errors scale factor, optical path difference OPD = 2*h*scale*sin(theta)
  • delim – delimiter between data columns
  • xscale – scaling factor for the mirror profile x-axis (for taking an arbitrary scaled axis, i.e. im mm)
  • x0 – shift of mirror longitudinal position [m]
Returns:

opIPM - imperfect plane mirror propagator
wpg.optical_elements.Mirror_plane_2d(orient, theta, length, range_xy, filename, scale=1, x0=0.0, y0=0.0, xscale=1.0, yscale=1.0, bPlot=False)[source]

Defining a plane mirror propagator with taking into account 2D surface height errors

Parameters:
  • orient – mirror orientation, ‘x’ (horizontal) or ‘y’ (vertical)
  • theta – incidence angle [rad]
  • length – mirror length, [m]
  • range_xy – range in which the incident WF defined [m]
  • filename – full file name with 2d mirror profile of three columns, x, y, and h(x, y) - heigh errors [m]
  • scale – scale factor, optical path difference OPD = 2*h*scale*sin(theta)
  • x0 – shift of mirror longitudinal position [m]
  • y0 – shift of mirror transverse position [m]
  • xscale – units of 1st column of filename, x[m]=x[nits]*xscale [m]
  • yscale – units of 1st column of filename, y[m]=y[nits]*yscale [m]
Returns:

opIPM - imperfect plane mirror propagator
class wpg.optical_elements.Screen(filename=None)[source]

Bases: wpg.optical_elements.Empty

class: Implements the Screen optical element

Constructor for the Screen class.

Parameters:filename (str) – Name of file to store wavefront data.
Raises:IOError – File exists.
propagate(wfr, propagation_parameters)[source]

Overloaded propagation for this element.

class wpg.optical_elements.Use_PP(auto_resize_before=None, auto_resize_after=None, releative_precision=None, semi_analytical_treatment=None, fft_resizing=None, zoom=None, zoom_h=None, zoom_v=None, sampling=None, sampling_h=None, sampling_v=None, srw_pp=None)[source]

Bases: object

Short version of propagation parameters. Should be used with wpg.beamline.Beamline

Params srw_pp:propagation parameters in srw style
auto_resize_after

Auto-Resize (1) or not (0) After propagation

auto_resize_before

Auto-Resize (1) or not (0) Before propagation

fft_resizing

Do any Resizing on Fourier side, using FFT, (1) or not (0)

get_srw_pp()[source]

Return SRW propagation parameters list. Useful for interoperations with SRW tools.

Returns:list of floats (propagation parameters)
releative_precision

Relative Precision for propagation with Auto-Resizing (1. is nominal)

sampling

Resolution modification factor at Resizing

sampling_h

Horizontal Resolution modification factor at Resizing

sampling_v

Vertical Resolution modification factor at Resizing

semi_analytical_treatment

Allow (1) or not (0) for semi-analytical treatment of quadratic phase terms at propagation

zoom

Range modification factor at Resizing (1. means no modification)

zoom_h

Horizontal Range modification factor at Resizing (1. means no modification)

zoom_v

Vertical Range modification factor at Resizing

wpg.optical_elements.VLS_grating(_mirSub, _m=1, _grDen=100, _grDen1=0, _grDen2=0, _grDen3=0, _grDen4=0, _grAng=0)[source]

Optical Element: Grating.

Parameters:
  • _mirSub – SRWLOptMir (or derived) type object defining substrate of the grating
  • _m – output (diffraction) order
  • _grDen – groove density [lines/mm] (coefficient a0 in the polynomial groove density: a0 + a1*y + a2*y^2 + a3*y^3 + a4*y^4)
  • _grDen1 – groove density polynomial coefficient a1 [lines/mm^2]
  • _grDen2 – groove density polynomial coefficient a2 [lines/mm^3]
  • _grDen3 – groove density polynomial coefficient a3 [lines/mm^4]
  • _grDen4 – groove density polynomial coefficient a4 [lines/mm^5]
  • _grAng – angle between the grove direction and the saggital direction of the substrate [rad] (by default, groves are made along saggital direction (_grAng=0))
Returns:

SRWLOptG: VLS grating propagator, struct SRWLOptG
wpg.optical_elements.WF_dist(nx, ny, Dx, Dy)[source]

Create a ‘phase screen’ propagator for wavefront distortions: A wrapper to SRWL struct SRWLOptT

Parameters:
  • nx – number of points in horizontal direction
  • ny – number of points in vertical direction
  • Dx – size in m
  • Dy – size in
class wpg.optical_elements.WPGOpticalElement[source]

Bases: object

Base class for optical elements.

wpg.optical_elements.calculateOPD(wf_dist, mdatafile, ncol, delim, Orient, theta, scale=1.0, length=1.0, xscale=1.0, x0=0.0, bPlot=False)[source]

Calculates optical path difference (OPD) from mirror profile and fills the struct wf_dist (struct SRWLOptT) for wavefront distortions

Params wf_dist:

struct SRWLOptT
Params mdatafile:
 

an ascii file with mirror profile data
Params ncol:

number of columns in the file
Params delim:

delimiter between numbers in an row, can be space (‘ ‘), tab ‘ ‘, etc
Params orient:

mirror orientation, ‘x’ (horizontal) or ‘y’ (vertical)
Params theta:

incidence angle
Params scale:

scaling factor for the mirror profile
Parameters:
  • xscale – scaling factor for the mirror profile x-axis (for taking an arbitrary scaled axis, i.e. im mm)
  • length – mirror length, m, default value 1 m
Returns:

filled struct SRWLOptT
wpg.optical_elements.create_CRL(directory, voids_params, _foc_plane, _delta, _atten_len, _shape, _apert_h, _apert_v, _r_min, _n, _wall_thick, _xc, _yc, _void_cen_rad=None, _e_start=0, _e_fin=0, _nx=1001, _ny=1001)[source]

This function build CLR or load it from file if it was created beforehand. Out/input filename builded as sequence of function parameters.

Adiitinal parameters (*args) passed to srwlib.srwl_opt_setup_CRL function

Parameters:
  • directory – output directory to save file.
  • voids_params – void params to build CRL and construct unique file name
  • _foc_plane – plane of focusing: 1- horizontal, 2- vertical, 3- both
  • _delta – refractive index decrement (can be one number of array vs photon energy)
  • _atten_len – attenuation length [m] (can be one number of array vs photon energy)
  • _shape – 1- parabolic, 2- circular (spherical)
  • _apert_h – horizontal aperture size [m]
  • _apert_v – vertical aperture size [m]
  • _r_min – radius (on tip of parabola for parabolic shape) [m]
  • _n – number of lenses (/”holes”)
  • _wall_thick – min. wall thickness between “holes” [m]
  • _xc – horizontal coordinate of center [m]
  • _yc – vertical coordinate of center [m]
  • _void_cen_rad – flat array/list of void center coordinates and radii: [x1, y1, r1, x2, y2, r2,…]
  • _e_start – initial photon energy
  • _e_fin – final photon energy
Returns:

SRWL CRL object
wpg.optical_elements.create_CRL_from_file(directory, file_name, _foc_plane, _delta, _atten_len, _shape, _apert_h, _apert_v, _r_min, _n, _wall_thick, _xc, _yc, _void_cen_rad=None, _e_start=0, _e_fin=0, _nx=1001, _ny=1001)[source]

This function build CLR or load it from file. Out/input filename builded as sequence of function parameters. Adiitinal parameters (*args) passed to srwlib.srwl_opt_setup_CRL function

Parameters:
  • directory – output directory
  • fiel_name – CRL file name
  • _foc_plane – plane of focusing: 1- horizontal, 2- vertical, 3- both
  • _delta – refractive index decrement (can be one number of array vs photon energy)
  • _atten_len – attenuation length [m] (can be one number of array vs photon energy)
  • _shape – 1- parabolic, 2- circular (spherical)
  • _apert_h – horizontal aperture size [m]
  • _apert_v – vertical aperture size [m]
  • _r_min – radius (on tip of parabola for parabolic shape) [m]
  • _n – number of lenses (/”holes”)
  • _wall_thick – min. wall thickness between “holes” [m]
  • _xc – horizontal coordinate of center [m]
  • _yc – vertical coordinate of center [m]
  • _void_cen_rad – flat array/list of void center coordinates and radii: [x1, y1, r1, x2, y2, r2,…]
  • _e_start – initial photon energy
  • _e_fin – final photon energy
Returns:

SRWL CRL object
wpg.optical_elements.mkdir_p(path)[source]

Create directory with subfolders (like Linux mkdir -p)

Parameters:path – Path to be created
wpg.optical_elements.Drift
wpg.optical_elements.Lens