Branching of solutions in Floquet-Bloch problem

This present work is limited to the same simple model of electromagnetic waves propagation and the differential equation of the second order with periodic factor. Long periodic Floquet problem is reduced, thus, to a series from 2*m-1 algebraic problems on values. Such values have various own vectors. For each of the unimodal matrixes the solution of a Floquet problem can be received separately as the solution of an algebraic own value problem. The result received in the present work is equally applicable to quantum Bloch problem in a periodic field.