lentil.power_spectrum(mask, pixelscale, rms, half_power_freq, exp, seed=None)[source]

Wavefront error defined by a Power Spectral Density (PSD) function.

  • mask (array_like) – Binary [0,1] mask defining pupil extent

  • pixelscale (float) – Physical size of each pixel in the resulting opd in meters.

  • rms (float) – RMS value of the PSD error in meters

  • half_power_freq (float) – Half-power frequency in number of cycles per pixel

  • exp (float) – Exponent of the inverse-power law

  • seed (int, optional) – Random seed used to initialize the pseudo-random number generator. If seed is None (default), the seed will be randomly generated from /dev/urandom if available or the system clock.


wfe – Masked wavefront error with requested PSD

Return type



  • Sidick (2009) Power Spectral Density Specification and Analysis of Large Optical Surfaces