Amer Eynas, Gren Per, Sjödahl Mikael
Opt Express. 2013 Oct 21;21(21):25316-23. doi: 10.1364/OE.21.025316.
A frequency tripled Q-switched Nd-YAG laser (wavelength 355 nm, pulse duration 12 ns) has been used to pump Coumarin 153 dye solved in ethanol. Simultaneously, a frequency doubled pulse (532 nm) from the same laser is used to probe the solvent perpendicularly resulting in a gain through stimulated laser induced fluorescence (LIF) emission. The resulting gain of the probe beam is recorded using digital holography by blending it with a reference beam on the detector. Two digital holograms without and with the pump beam were recorded. Intensity maps were calculated from the recorded digital holograms and used to calculate the gain of the probe beam due to the stimulated LIF. In addition numerical data of the local temperature rise was calculated from the corresponding phase maps using Radon inversion. It was concluded that about 15% of the pump beam energy is transferred to the dye solution as heat while the rest is consumed in the radiative process. The results show that pulsed digital holography is a promising technique for quantitative study of fluorescent species.
一台三倍频调Q Nd:YAG激光器（波长355纳米，脉冲持续时间12纳秒）被用于泵浦溶解在乙醇中的香豆素153染料。同时，来自同一激光器的倍频脉冲（532纳米）被用于垂直探测溶剂，通过受激激光诱导荧光（LIF）发射产生增益。通过在探测器上与参考光束混合，利用数字全息术记录探测光束的增益。记录了有无泵浦光束时的两张数字全息图。从记录的数字全息图计算强度图，并用于计算受激LIF导致的探测光束增益。此外，利用拉东反演从相应的相位图计算局部温度上升的数值数据。得出的结论是，约15%的泵浦光束能量以热的形式转移到染料溶液中，其余的在辐射过程中消耗。结果表明，脉冲数字全息术是一种用于荧光物质定量研究的有前途的技术。
