Time resolved digital-holographic analysis of femtosecond laser-induced photodisruption
Time resolved digital-holographic analysis of femtosecond laser-induced photodisruption
复制标题
飞秒激光诱导光致破裂的时间分辨数字全息分析
DOI：
10.1117/12.2211013
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Ripken T
中科院分区：
文献类型：
--
作者：
Saerchen E;Wenzel J;Antonopoulos G;Krueger A;Lubatschowski H;Ripken T
具有低脉冲能量(<；1μJ)和高重复频率(MHz)的飞秒激光振荡器系统越来越多地用于精确、快速和安全的眼科手术。因此，激光组织相互作用过程对于优化和改进现有和未来的手术方案具有重要意义。此外，使用更快的激光系统会导致意外的自感应相互作用效应，即飞秒激光脉冲以一种改变后续激光脉冲的焦点的方式改变材料中的附近区域。利用高重复频率、脉冲能量为66nJ的飞秒振荡激光系统在水中产生光破裂。由于眼部组织主要由水组成，故采用水作为眼部组织的体模材料。一种定制的数字全息系统被用来测量从皮秒到光破坏发生后的几秒钟的时间材料修改。对于样品的照明，我们在泵浦-探测配置中使用了连续光源或飞秒激光脉冲本身。该全息系统为几十分之一微米的全视场提供了相位差Δφ的定量数据。相位差相当于激光引起的材料折射率的变化，这会改变后续激光脉冲的聚焦条件，并可能影响手术结果。我们在最初的皮秒内获得了最大的Δφ变化，随后在几毫秒内Δφ缓慢松弛。激光诱导材料修饰的时间分辨测量结果将有助于眼科手术中扫描方案的优化。
Femtosecond laser oscillator systems with low pulse energy (< 1 μJ) and high repetition rate (MHz) are increasingly used for precise, fast and safe eye surgery. Therefore, the laser tissue interaction process is of great interest to optimize and improve established and future surgical protocols. Besides, using faster laser systems leads to unintended self-induced interaction effects, where a femtosecond laser pulse modifies the vicinity in the material in such a way that the focus of following laser pulses is changed. We used a femtosecond oscillator laser system with high repetition rate and 66 nJ pulse energy to produce photodisruption in water. Water was used as phantom material for ocular tissue, because tissue mainly consists of water. A custom made digital-holographic system was used to measure the temporal material modification from picoseconds until seconds after occurrence of the photodisruption. For illumination of the sample we used either a continuously light source or the femtosecond laser pulse itself in a pump-probe configuration. The holographic system provides quantitative data of phase difference Δφ for the full field of view of several tenth of micrometers. Phase difference is equivalent to the laser induced change in the material’s refractive index which can alter focusing conditions of following laser pulses and might impair surgical outcome. We obtained the largest change in Δφ during the first picoseconds, followed by a slow relaxation of Δφ within some milliseconds. The results of time resolved measurements of the laser induced material modification will help to optimize scanning schemes in ocular surgery.
登录
查看更多内容
在 der Augenheilkunde 中更新 Femtosekundenlaser-Technologien
DOI：
--
发表时间：
2013
期刊：
Klin Monatsbl Augenheilkd
影响因子：
--
作者：
H. Lubatschowski
通讯作者：
H. Lubatschowski
影响因子：
2.8
作者：
Salomao, Marcella Q.;Wilson, Steven E.
通讯作者：
Wilson, Steven E.
2014 年折射激光外科创新
DOI：
10.1007/s00347-013-2993-9
发表时间：
2014
期刊：
Der Ophthalmologe
影响因子：
--
作者：
T. Seiler
通讯作者：
T. Seiler
飞秒激光在透明电介质中制造环状结构
DOI：
--
发表时间：
2015
期刊：
影响因子：
--
作者：
S. Vartapetov;D. Ganin;K. Lapshin;A. Obidin
通讯作者：
A. Obidin
激光辅助白内障手术：概述
DOI：
--
发表时间：
--
期刊：
影响因子：
--
作者：
A. Hartwig;Dipl;Phd Faao;S. Kheterpal;Ma Frcs Mrcophth;Jay Dermott;Dopt Bsc Ffdo;Clare O;Donnell Phd;Mba Mcoptom;Faao Fbcla
通讯作者：
Faao Fbcla