It's well known that both thermal self-defocusing effect and reverse saturated absorption can lead to optical limiting.
众所周知，热自散焦效应和反饱和吸收效应都能导致光限幅。
2
The discussion is focused on both self-focusing and self-defocusing medium. Some results with potential applications are given.
针对自聚焦和自散焦介质分别进行了讨论，获得了具有潜在应用价值的结论。
3
To contract the circular beam symmetrically, the co-propagation of the bright and dark beams in three-dimensional self-defocusing media is studied systematically.