We studied the cooperative generation of non-equilibrium localized phonons (fractons), which can be observed in experimental studying of the relaxation of groups of excited atoms after the passage of short laser pulse through the glass sample. The increasing of the absorption coefficient in the process of the excitation of glasses by short laser pulse with relatively small power is conditioned by the generation of the non-equilibrium coherent localized phonons in the process of the relaxation of non-equilibrium excitations, which strongly change the topology of the random potential and, thus, open a new channel of the interband light absorption. ©2000 American Institute of Physics.