Visualizing the expansion of particles of different size in a laser-ablated plume is useful for understanding the mechanism of the pulsed-laser deposition process. In our previous work that the crystalline hydroxyapatite content in a coating layer decreased with increasing H₂O gas pressure. We concluded that ablated atoms and ions, which were immediately changed into crystalline hydroxyapatite, were stopped before reaching the substrate in the H₂O pressure range. In the present study, the expansion behavior of ablated droplets and atoms in H₂O gas was measured independently. Droplets were also measured via Mie scattering images using a second probe laser beam and were found to not be affected by the ambient gas pressure. However, the excited Ca atoms and ions in this H₂O pressure range were effectively prevented from reaching the substrate. These confirm that the decrease in the crystalline hydroxyapatite content was caused by the increase in the ambient gas pressure.

可视化激光烧蚀羽流中不同尺寸的粒子的膨胀对于理解脉冲激光沉积过程的机制非常有用。在我们之前的工作中，涂层中的结晶羟基磷灰石含量随着 H ₂ O 气压的增加而降低。我们得出的结论是，烧蚀的原子和离子在到达 H ₂ O 压力范围内的基材之前停止了，这些原子和离子立即变成了结晶羟基磷灰石。在本研究中，烧蚀液滴和原子在 H _{2 中}的膨胀行为O 气体是独立测量的。还使用第二个探测激光束通过米氏散射图像测量液滴，发现液滴不受环境气压的影响。然而，在该 H ₂ O 压力范围内被激发的 Ca 原子和离子被有效地阻止到达衬底。这些证实结晶羟基磷灰石含量的降低是由环境气压的增加引起的。