高能激光大气传输中热晕与自聚焦的比较

Comparison of Thermal Blooming and Self-focusing about Propagation of High Energy Laser in Atmosphere

通过分析激光在大气中传输所产生热晕效应和自聚焦效应的临界功率PTB和PK表明,在同样大气条件下,产生自聚焦的临界功率PK比产生热晕的临界功率PTB大约高5个量级。另外,分析了在同样激光功率下,不同宽度的脉冲激光在大气中传输时的热晕效应与自聚焦效应,一般情况下,微秒量级的脉冲激光在大气传输中的自聚焦效应可忽略,而对于超短飞秒脉冲激光,必须考虑自聚焦效应对传输的影响。

By analyzing the critical value of thermal blooming and self -focusing, it is shown that the critical value of self-focusing is about five magnitude larger than thermal blooming s in the same atmospheric conditions. In addition, at the same power of pulse laser, the width of pulse also has impact on the two nonlinear effects. If the pulse width is above microsecond, the self-focusing can be neglected. However, when the length of pulse decreases to ultrashort, self- focusing must be considered for the propag...