A Study in Diffraction Microscopy with Special Reference to X-Rays

The factors which affect resolution in diffraction microscopy are studied. The inequality pλ>4nd/N is a necessary condition for making good holograms, where p is the distance between source and film, d is the diameter of the source, and λ is its wavelength, n is the number of recorded central bands of the diffraction pattern, and N is the resolving power of the film. The minimum theoretical resolvable distance between two point objects is limited by d and N but not by the wavelengths used in the analysis and reconstruction. Possible applications to the focusing of x-rays by Gabor techniques and by a single Fresnel zone plate are considered.