A STUDY OF SYMMETRICAL LLL X-RAY POLYLITHIC INTERFEROMETERS ON THE BASIS OF THE TAKAGI EQUATIONS

The Takagi approach to the dynamical theory of x-ray diffraction has b een used to study LLL x-ray polylithic interferometers. A computationa l tool has been implemented to solve the Takagi equations with boundar y conditions of the Cauchy type. The mean intensity, visibility and in itial phase of the x-ray fringes generated by displacing the analyzer have been calculated for any wavefront, absorption of the incident rad iation and for the most common geometric arrangements. Geometric aberr ations of different kinds, introduced during interferometer preparatio n, are considered. The curve relevant to the calculated difference bet ween the reflected and transmitted x-ray fringes as a function of anal yzer rotation is in agreement with the experimental curve.