Dynamical contrast of the topographic image of a crystal with continuous X-ray radiation. II. A theoretical study of the polychromatic interference fringes

A theoretical analysis is given of the contrast of the topographic image of a perfect crystal with continuous radiation. Conditions for observation of polychromatic interference fringes in this diffraction scheme are analysed on the basis of Kato's dynamical theory of spherical-wave diffraction. The effect of polarization and azimuthal divergence of X-rays on the contrast of topographs is also discussed.