Scalogram Measurement System of Ultrashort Optical Pulse Using Femtosecond Pulse Laser

本研究的目的是开发一种新的光学方法，可以直接同时测量和分析超短光脉冲作为尺度图的时间、空间和时间频率之间的关系，并设计和构建一种能够实现这种超快尺度图测量和分析的新型光学系统。为此，我们设计并构建了一种利用小波变换实现多分辨率分析的光学系统。该系统利用光学方法实现了超短脉冲的小波变换，并通过电子后置计算实现了各种信号的剖面检索。为了验证所开发系统的能力，我们尝试了几个实验。实验结果表明，该系统可以测量飞秒超短脉冲的尺度图。为了证明所构建系统的能力，我们获得了几个多分辨率尺度图，改变了时间分辨率或光谱分辨率。研究结果表明，所开发的系统可以作为超快的尺度图处理器，为超短光脉冲的测量和分析提供有用的工具。

The object of this research is to develop the new optical method that can directly and simultaneously measure and analyze the relation among time, space and temporal frequency of ultrashort optical pulse as a scalogram, and to design and construct a new optical system capable of realizing such ultrafast measurement and analysis of scalogram.For this purpose, we designed and constructed a new optical system which was able to achieve multi-resolutional analysis by using wavelet transform. In the developed system, wavelet transform of an ultrashort pulse is optically achieved, and retrieval of profiles of various signals is attained with electronic post calculation. To verify the ability of the developed system, we attempted several experiments.Through experimental results, we confirmed that the proposed system can measure scalogram of an femtosecond ultrashort pulse. To demonstrate the capability of the constructed system, we acquire several multi-resolutional scalograms, changing either temporal resolution or spectral one. From the results of this research, we can obtain the important knowledge that the developed system would work as an ultrafast processor for scalogram and would be useful tool for measurement and analysis of ultrashort optical pulses.