holab.physics

This module provides functionalities for computing holograms based on wave equations, particularly the Helmholtz equation.

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compute_hologram(lens, source, f0, lens_thickness, projection_distance, *, maxiter_helmholtz_solver=100, tol_helmholtz_solver=0.001, remove_padding=True, background=water)

Solves the helmholtz equation locally around the lens, and projects the field to the hologram plane using the angular spectrum method.

Parameters:

Name	Type	Description	Default
lens	PhysicalObject	The lens object. This needs to be a physical object with a "as_medium_on_environment" method.	required
source	FourierSeries	The source field.	required
f0	float	The frequency of the source.	required
lens_thickness	float	The thickness of the lens. This is used to determine the location of the plane used to extract the field to be projected.	required
projection_distance	float	The distance from the lens to the hologram plane. This is used to determine the location of the plane used to extract the field to be projected. It is measured from the output plane of the lens.	required
maxiter_helmholtz_solver	int	The maximum number of GMRES iterations for the helmholtz solver. Defaults to 100.	100
tol_helmholtz_solver	float	The tolerance for the helmholtz solver. Defaults to 0.001.	0.001
remove_padding	bool	Whether to remove the padding added by the angular spectrum method. Defaults to True.	True
background	Material	The background material. Defaults to water.	water

Returns:

Name	Type	Description
FourierSeries	FourierSeries	The hologram field.

project_to_hologram_plane(pressure, f0, lens_thickness, plane_distance, remove_padding=True, background=water)

Projects a field to the hologram plane using the angular spectrum method.

Parameters:

Name	Type	Description	Default
pressure	FourierSeries	The field to be projected. This needs to be a 3D wavefield from which a planar slice will be extracted.	required
f0	float	The frequency of the field.	required
lens_thickness	float	The thickness of the lens. This is used to determine the location of the plane used to extract the field to be projected.	required
plane_distance	float	The distance from the lens to the hologram.	required
remove_padding	bool	Whether to remove the padding added by the angular spectrum method.	True
background	Material	The background material. Defaults to water.	water

solve_helmholtz(medium, source, f0, maxiter=100, tol=0.001)

A thin wrapper around jwave.acoustics.time_harmonic.helmholtz_solver.

Parameters:

Name	Type	Description	Default
medium	Medium	The medium in which the field is to be solved.	required
source	FourierSeries	The source field.	required
f0	float	The frequency of the source.	required
maxiter	int	The maximum number of GMRES iterations (the internal solver used by helmholtz_solver).	100
tol	float	The tolerance for the GMRES solver (the internal solver used by helmholtz_solver).	0.001

Returns:

Name	Type	Description
FourierSeries	FourierSeries	The resulting acoustic field.