fhf_wp

pyrost.bin.fhf_wp(double complex[::1] u0, double dx0, double dx, double z, double wl)

One-dimensional discrete form of Fraunhofer diffraction performed by the means of Fast Fourier transform.

Parameters
  • u0 (numpy.ndarray) – Wavefront at the plane upstream.

  • dx0 (float) – Sampling interval at the plane upstream [um].

  • dx (float) – Sampling interval at the plane downstream [um].

  • z (float) – Propagation distance [um].

  • wl (float) – Incoming beam’s wavelength [um].

Returns

Wavefront at the plane downstream.

Return type

numpy.ndarray

Notes

The Fraunhofer integral transform is defined as:

\[u^{\prime}(x^{\prime}) = \frac{e^{-j k z}}{j \sqrt{\lambda z}} e^{-\frac{j k}{2 z} x^{\prime 2}} \int_{-\infty}^{+\infty} u(x) e^{j\frac{2 \pi}{\lambda z} x x^{\prime}} dx\]