利用Q-开关Nd:YAG激光器产生的1.06mm、140ns 的脉冲激光聚焦在空气中的石英靶上,采集激光诱导的石英等离子体发射光谱,在室温大气压下利用高速摄影机对激光加工过程中伴随产生的等离子体的动态过程进行监测研究;在局部热力学平衡条件(LET)近似下,估算了等离子体电子平均温度随时间的变化规律;提出室温下等离子体加工石英微通道过程中等离子体性质发生变化的特征时间为1000ms和400ms;影响等离子体加工质量的关键因素可能包括通道内部气压值。

Using Nd: YAG laser (with a wavelength of 1064nm and a pulse width of 140ns) ablate quartz target in air in the room temperature at atmosphere condition to observe the emission spectra of quartz plasma. A high velocity camera was used to capture the images of the laser-induced plasma under the room temperature in air during the laser micromachining to study the dynamic character of the plasma. Under the model of local thermodynamic equilibrium, the average temperatures of quartz plasma are deduced with time by the relative line intensities. And the characteristic time of the plasma change is 1000μs and 400μs. The possible factor that may impact the plasma dynamic is the interior pressure of the tube.