abtem.tilt

abtem.tilt#

Module for simulating beam tilt.

Module Contents#

Classes#

AxisAlignedBeamTilt

Class describing tilt(s) aligned with an axis.

BaseBeamTilt

BeamTilt

Class describing beam tilt.

BeamTilt2D

Class describing 2D beam tilt.

Functions#

precession_tilts

Tilts for electron precession at a given precession angle.

validate_tilt

Validate that the given tilt is correctly defined.

Data#

TiltType

TiltType2D

API#

class abtem.tilt.AxisAlignedBeamTilt(...)[source]#

Bases: abtem.distributions.DistributionFromValues

Class describing tilt(s) aligned with an axis.

Parameters:

  • tilt (array of BeamTilt) – Tilt along the given direction with an optional spread of values.

  • direction (str) – Cartesian axis, should be either ‘x’ or ‘y’.

Initialization

property direction: str#

Tilt direction.

property ensemble_axes_metadata: list[AxisMetadata]#
property metadata#
property tilt: float | BaseDistribution#

Beam tilt [mrad].

class abtem.tilt.BaseBeamTilt(...)[source]#

Bases: abtem.transform.WavesToWavesTransform

apply(...) → Waves[source]#

Apply tilt(s) to (an ensemble of) wave function(s).

Parameters:

  • waves (Waves) – The wave function(s) to apply the tilt to.

  • max_batch (int or str, optional) – The maximum batch size used in the calculation. If ‘auto’, the batch size is automatically determined. Default is ‘auto’.

Returns:

waves_with_tilt

Return type:

Waves

class abtem.tilt.BeamTilt(...)[source]#

Bases: abtem.tilt.BaseBeamTilt

Class describing beam tilt.

Parameters:

tilt (tuple of float) – Tilt along the x and y axes [mrad] with an optional spread of values.

Initialization

property ensemble_axes_metadata: list[AxisMetadata]#

Metadata describing (an ensemble of) tilted wave function(s).

property metadata#

Metadata describing the tilt.

property tilt: tuple[float, float] | BaseDistribution#

Beam tilt angle [mrad].

class abtem.tilt.BeamTilt2D(...)[source]#

Bases: abtem.tilt.BaseBeamTilt

Class describing 2D beam tilt.

Parameters:

tilt (array of BeamTilt) – Tilt along the x and y axes [mrad] with an optional spread of values.

Initialization

property ensemble_axes_metadata: list[AxisMetadata]#
property ensemble_shape: tuple[int, int]#
property metadata#
property shape: tuple[int, int]#
property tilt_x: BaseDistribution | float#

Beam tilt along the x-axis.

property tilt_y: BaseDistribution | float#

Beam tilt along the y-axis.

abtem.tilt.TiltType#

None

abtem.tilt.TiltType2D#

None

abtem.tilt.precession_tilts(...)[source]#

Tilts for electron precession at a given precession angle.

Parameters:

  • precession_angle (float) – Precession angle [mrad].

  • num_samples (int) – Number of tilt samples.

  • min_azimuth (float, optional) – Minimum azimuthal angle [rad]. Default is 0.

  • max_azimuth (float, optional) – Maximum azimuthal angle [rad]. Default is $2 pi$.

  • endpoint – If True, end is max_azimuth. Otherwise, it is not included. Default is False.

Returns:

array_of_tilts – Array of xy-tilt angles [mrad].

Return type:

2D array

abtem.tilt.validate_tilt(...) → BeamTilt | BeamTilt2D | AxisAlignedBeamTilt[source]#

Validate that the given tilt is correctly defined.