| 1. | Since 1990 ' s , a variety of methods , such as geometrical optical method , mode - conversion method , optical holographic method , computer - generated holography method , transverse - mode selection method , hollow fiber method and nonlinear optical method , have been used to generate the dark hollow beams ( dhbs )
从90年代起，各种技术，如几何光学法、模式转换法、光学全息法、计算全息法、横模选择法、中空光纤法、非线性方法等，被相继用来产生暗中空光束，并得到一些很好的实验结果。 |
