Analytic Beams

PlaneWaveBeamProfile	Component for constructing plane wave beam data.
GaussianBeamProfile	Component for constructing Gaussian beam data.
AstigmaticGaussianBeamProfile	Component for constructing astigmatic Gaussian beam data.
ThinLensProfile	Component for constructing focused beam data using a vectorial thin-lens spectrum.

Thin-Lens Focused Beams

The ThinLensProfile class evaluates a focused vectorial beam from a thin-lens angular spectrum. It is useful for inspecting the analytic focused field directly, or for constructing a field profile that matches the ThinLensBeam source and ThinLensOverlapMonitor.

The numerical_aperture sets the maximum propagation angle in the background medium and may exceed one in high-index media as long as it is less than the real background refractive index. When fill_lens=True, the pupil is a uniformly illuminated circular aperture. When fill_lens=False, the pupil is under-filled by a Gaussian beam, and both lens_diameter and beam_diameter must be provided. Increase num_plane_waves when checking high-NA fields or fine focal-plane structure.

freq0 = td.C_0 / 1.55

thin_lens_profile = ThinLensProfile(
    center=(0, 0, 0),
    size=(8, 8, 0),
    freqs=[freq0],
    numerical_aperture=0.7,
    waist_distance=0,
    fill_lens=True,
    num_plane_waves=101,
)

field_data = thin_lens_profile.field_data

The waist_distance parameter is the signed axial distance from the focal plane to the sampled beam plane, measured in the beam propagation frame. The lens_offset parameter shifts the focal field in the two tangential directions through a pupil phase ramp. The entries follow the tangential-axis order obtained by removing the normal axis from (x, y, z); for example, a y-normal beam uses (x, z). It does not model a decentered finite aperture with clipping or changed pupil amplitude.

For angled beams, angle_theta and angle_phi rotate the ideal focused beam and its pupil into the requested propagation direction. This represents a tilted optical axis and a pupil perpendicular to that axis; it does not model aberrations from a fixed physical lens illuminated at oblique incidence.