在雷射的眾多應用中，經常因為光強呈現高斯分布，而造成許多應用上的限制，因此需要光束整形的技術來將原本分布不均勻的光強，經過系統後改變成光強分布均勻的平頂光束。本論文分別用市售的被動式光束整形器π Shaper以及空間光調變器(spatial light modulator，SLM)構成的主動式光束整形來達成此目的，並搭配自製的Shack-Hartmann波前感測器(Shack-Hartmann wavefront sensor，SHWS)來了解波前的變化情形。自製SHWS的波前感測部分是藉由感光耦合元件(charge coupled device，CCD)與微透鏡陣列的組合，量測CCD上的聚焦光點偏移位置得到波前資訊，接著以Zernike模型重建波前。
被動式光束整形器是運用折射的影響，藉由多組非球面透鏡組的組合來改變光強的分布情形，這邊直接使用光束整形器π Shaper來實作，並與實驗室的系統結合，量測螢光試片的螢光強度分布情形。而主動式光束整形則是藉由繞射的方式，利用電腦來計算反覆傅立葉轉換演算法(iterative Fourier transform algorithm)並模擬出全像片與結果，這邊分別針對三種演算法模擬：Gerchburg-Saxton、adaptive-additive和mixed region amplitude freedom，並且用模擬產生的全像片拿來顯示於SLM上進行實作，而得到了初步的光束整形成果。

Some laser applications are limited due to the Gaussian distribution intensity. A beam shaping technique is attempted to convert the original non-uniform distribution of intensity to a uniform flat-top distribution beam. Both of the commercial passive π Shaper and active spatial light modulator (SLM) are adopted for beam shaping. A lab-made Shack-Hartmann wavefront sensor (SHWS) has been developed for detecting wavefront variation. The wavefront information is analyzed by positioning the focal spot shift on a charge-coupled device (CCD), and uses the Zernike polynomial model to reconstruct the wavefront data. The passive π Shaper is applied by refraction effect, using several pairs of aspheric lens to modify the intensity distribution. Furthermore, the active way is applied with diffraction effect, using iterative Fourier transform algorithm to simulate the hologram and compared with three kinds of algorithm: Gerchburg-Saxton (GS), adaptive-additive (AA), and mixed region amplitude freedom (MRAF). The hologram is applied on the SLM to modify the beam intensity profile and the preliminary results are demostrated.

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