pybsm.otf.functional.circular_aperture_OTF_with_defocus

pybsm.otf.functional.circular_aperture_OTF_with_defocus(*, u: ndarray, v: ndarray, wavelength: float, D: float, f: float, defocus: float) → ndarray

Calculate MTF for an unobscured circular aperture with a defocus aberration.

From “The frequency response of a defocused optical system” (Hopkins, 1955) Variable changes made to use angular spatial frequency and approximation of 1/(F/#) = sin(a). Contributed by Matthew Howard.

Parameters:

  • u – angular spatial frequency coordinates (rad^-1)

  • v – angular spatial frequency coordinates (rad^-1)

  • wavelength – wavelength (m)

  • D – effective aperture diameter (m)

  • f – focal length (m)

  • defocus – focus error distance between in focus and out of focus planes (m). In other words, this is the distance between the geometric focus and the actual focus.

Raises:
ZeroDivisionError:

if wavelength or D is 0

Returns:

H:

OTF at spatial frequency (u,v) (unitless)

NOTE:

Code contributed by Matt Howard