ИСТИНА

It is considered a problem of incidence of a plane wave on a periodic layer having finite or infinite width. The layer has periodic surface as well as periodic permittivity inside the layer. The refelected, absorbed and passed radiation is calculated using the method of parallel projections. This method allows to reduce the problem to the system of ordinary differential equations. The computer realization of the algorithm was implemented using the C++ programming language. Source code of the program could be found at https://bitbucket.org/Jclash/dpproj. The web-interface (http://ipmnet.ru/~knyaz/diffraction.html) was used to remotely run computations on a supercomputer. The accuracy was verified on a several cases that allow analytical solutions. The method could be used in solving direct and inverse problems of sea surface radiometry, lithography, acoustics.