Sharma R P, Gupta Pradeep Kumar, Singh Ram Kishor, Strickland D
Opt Lett. 2016 Apr 1;41(7):1423-6. doi: 10.1364/OL.41.001423.
The propagation characteristics of a spatial Gaussian laser pulse have been studied inside a gradient-index structured crystalline lens with constant-density plasma generated by the laser-tissue interaction. The propagation of the laser pulse is affected by the nonlinearities introduced by the generated plasma inside the crystalline lens. Owing to the movement of plasma species from a higher- to a lower-temperature region, an increase in the refractive index occurs that causes the focusing of the laser pulse. In this study, extended paraxial approximation has been applied to take into account the evolution of the radial profile of the Gaussian laser pulse. To examine the propagation characteristics, variation of the beam width parameter has been observed as a function of the laser power and initial beam radius. The cavitation bubble formation, which plays an important role in the restoration of the elasticity of the crystalline lens, has been investigated.
研究了空间高斯激光脉冲在具有激光与组织相互作用产生的恒定密度等离子体的梯度折射率结构晶状体内部的传播特性。激光脉冲的传播受到晶状体内部产生的等离子体引入的非线性的影响。由于等离子体粒子从高温区域向低温区域移动，导致折射率增加，从而使激光脉冲聚焦。在本研究中，应用了扩展傍轴近似来考虑高斯激光脉冲径向分布的演化。为了研究传播特性，观察了束宽参数随激光功率和初始束半径的变化。还研究了在晶状体弹性恢复中起重要作用的空化泡形成。
