<p>We study diffraction of an elctromagnetic wave by a cylinder made of an artificial magnetodielectric, which is a photonic crystal consisting of hollow metal cylinders. The problem is solved using two developed mathematical models of the device under study. New algorithms and software have been created. In the first model, equivalent anisotropic dielectric permittivity and magnetic permeability are introduced based on the calculation of a three-dimensional photonic crystal. The near field of a cylindrical magnetodielectric lens with these parameters is studied. In the second model, the problem of diffraction on a large (several thousand) number of metal cylinders is solved. This solution is used for calculating a real cylindrical lens. A comparison of the results obtained within the framework of these two models shows that the accuracy of calculation of focusing devices made of photonic crystals is sufficient for practice.</p>