超快雷射系統中光學色散會使雷射脈衝寬度變寬，理論上脈衝的瞬時功率也會下降，在非線性光學中例如多光子激發螢光顯微術應用上有嚴重影響，且光學色散在不同的系統上可能存在著動態變化，在不確定系統上的光學色散量值下，本文在不只是靜態的光學色散干擾下，連動態的情況也可以將光學色散中的二階項(group delay dispersion，GDD)做修正，並應用在實驗室自製多光子激發螢光顯微術(multiphoton excited fluorescence microscopy，MPEFM)中。
本文主要所使用的脈衝量測技術為頻率光學解析開關(frequency resolved optical gating，FROG)，在GRENOUILLE (grating-eliminated no-nonsense observation of ultrafast incident laser light e-fields)架構下以一個脈衝激發二倍頻晶體，激發後的時頻圖(spectrogram)資訊成像在CMOS相機上，由DOES (direct optical-dispersion estimation by spectrogram)演算法在現場可程式化邏輯閘陣列(field programmable gate array，FPGA)分析GDD，而脈衝補償技術為可調式聚焦鏡(deformable mirror，DM)脈衝壓縮器，在FPGA中使用PI控制器(proportional integral controller)在每次量測過後可計算下一步的DM須執行的修正量，在多次控制器迴圈的執行下將GDD收斂使脈衝達到轉換極限下的狀態，補償後脈衝雷射導入MPEFM系統，在靜態光學色散補償與動態光學色散補償等實驗中控制器迴圈以100 Hz的速度補償下，平均花費50 ms 即可將脈衝補償至轉換極限下，而多光子影像強度可提升至逼近理論極限的1.3~1.4倍。

The optical dispersion effect in ultrafast pulse laser systems broadens the laser pulse duration and reduces the theoretical peak power. The present study proposes an adaptive ultrashort pulse compressor for compensating the optical dispersion using a direct optical-dispersion estimation by spectrogram (DOES) method. The DOES has fast and accurate computation time which is suitable for real time controller design. In the proposed approach, the group delay dispersion (GDD) and its polarity are estimated directly from the delay marginal of the trace obtained from a single-shot frequency-resolved optical gating (FROG). The estimated GDD is then processed by a closed-loop controller, which generates a command signal to drive a linear deformable mirror as required to achieve the desired laser pulse compression. The dispersion analysis, control computation, and deformable mirror control processes are implemented on a single field programmable gate array (FPGA). It is shown that the DOES dispersion computation process requires just 0.5 ms to complete. Moreover, the proposed pulse compressor compensates for both static dispersion and dynamic dispersion within five time steps when closed-loop controller is performed at a frequency of 100 Hz. The experimental results show that the proposed pulse compressor yields an effective fluorescence intensity improvement in a multiphoton excited fluorescence microscope (MPEFM).

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