ideal_optical_transfer_function

  IDEAL_OPTICAL_TRANSFER_FUNCTION - ideal optical transfer function as a function of spatial frequency

  OTF_VALUE = IDEAL_OPTICAL_TRANSFER_FUNCTION(V)

  Computes the optical transfer function of an ideal diffraction-limited imaging system:
    OTF_VALUE = 2/pi * (acos(abs(v)) - abs(v).*sqrt(1-v.*v))

  V is the spatial frequency, relative to the high spatial frequency cut off V_cutoff (V_cutoff := 1).

  From Wikipedia:

  Example:
     v = 0:0.001:1;
     otf = ideal_optical_transfer_function(v);
     figure;
     plot(v,otf);
     xlabel('Spatial frequency (relative to max cut-off)');
     ylabel('Contrast');