transfer

Module to describe the contrast transfer function (CTF) and the related apertures.

Functions

cartesian2polar(cartesian)	Convert between Cartesian and polar aberration coefficients.
hard_aperture(alpha, semiangle_cutoff)	Calculates an array with a disk of ones and a soft edge.
nyquist_sampling(semiangle_cutoff, energy)	Calculate the Nyquist sampling.
point_resolution(Cs, energy)	Calculate the Scherzer point resolution.
polar2cartesian(polar)	Convert between polar and Cartesian aberration coefficients.
scherzer_defocus(Cs, energy)	Calculate the Scherzer defocus.
soft_aperture(alpha, phi, semiangle_cutoff, ...)	Calculates an array with a disk of ones and a soft edge.

Classes

Aberrations([aberration_coefficients, ...])	Phase aberrations.
Aperture(semiangle_cutoff[, soft, energy, ...])	A circular aperture cutting off the wave function at a specified angle, employed in both STEM and HRTEM.
BaseAperture([semiangle_cutoff, energy, ...])	Base class for apertures.
BaseTransferFunction([energy, extent, gpts, ...])	Base class for transfer functions.
Bullseye(num_spokes, spoke_width, num_rings, ...)	Bullseye aperture.
CTF([semiangle_cutoff, soft, focal_spread, ...])	The contrast transfer function (CTF) describes the aberrations of the objective lens in HRTEM and specifies how the condenser system shapes the probe in STEM.
SpatialEnvelope(angular_spread[, ...])	Envelope function for simulating partial spatial coherence in the quasi-coherent approximation.
TemporalEnvelope(focal_spread[, energy, ...])	Envelope function for simulating partial temporal coherence in the quasi-coherent approximation.
Vortex(quantum_number, semiangle_cutoff[, ...])	Vortex-beam aperture.
Zernike(center_hole_cutoff, phase_shift, ...)	Zernike aperture.