The effect of self-induced transparency is investigated for a three-level system with a V-scheme of the allowed transitions in the case where one of the transitions is resonant while another one is quasiresonant. The generalized system of the wave and material equations for the resonant transition, taking into account the presence of a quasiresonant transition, is derived. This system is integrable, and its soliton solutions are investigated. It is shown that quasiresonant transition has an influence on the profile of the optical soliton and leads to its phase modulation. The conditions under which the propagation of the soliton is followed by the full inversion of the populations of quantum levels of the resonant transition are established.

对于三级系统，在其中一个跃迁为共振而另一个跃迁为准共振的情况下，使用允许转移的V型方案研究了自感应透明的影响。推导了考虑到准谐振跃迁存在的，用于谐振跃迁的波动方程和材料方程的广义系统。该系统是可集成的，并且研​​究了其孤子解决方案。结果表明，准共振跃迁对孤子的轮廓有影响，并导致其相位调制。建立了在孤子的传播之后共振跃迁的量子能级完全反转的条件。