The concept of amplitude-wavelength space applied to the development of an x-ray optic provides a means of summarizing and unifying the complex data associated with each stage of its development: the specification; manufacturing tolerances; and etrology. The determination of manufacturing tolerances requires calculation of the image aberrations of perturbed optical systems and is most usefully carried out using a modified asymptotic Debye theory. Its range of applicability and that of other theories is illustrated in amplitude-wavelength space. Subnanometer perturbations are measured by mechanical or optical techniques, and the measuring instruments are calibrated by means of x-ray interferometry in terms of the primary standards of length.
A. Franks, B. Gale, and M. Stedman, "Grazing incidence optics:amplitude-wavelength mapping as a unified approach to specification, theory, and metrology," Appl. Opt. 27, 1508-1517 (1988)