本篇論文主要是使用染料摻雜膽固醇液晶製作一個由光引致、可空間調控輸出雷射波長的雷射元件，以平面膽固醇液晶結構作為共振腔，在樣品上的不同位置打入激發光，得到輸出不同波長的雷射訊號，其波長可涵蓋可見光的紅色到綠色範圍，最大可空間調控雷射波長範圍為134nm。在這個實驗中，我們主要使用一種光敏材料AzoM，藉由光致同素異構化來調控膽固醇液晶樣品的螺距來達到可空間調控雷射特性之目的。我們也發現光敏材料摻入具有不同旋性的膽固醇液晶後，反射波段會在照UV光後產生紅位移或藍位移，兩者皆可做成可空間調控輸出雷射波長的雷射元件。另外，此可空間調控特性於樣品上寫入後，可分別經由照射均勻綠光快速消除與經由熱自然緩慢消除，並且，在消除後，尚可再將可空間調控雷射特性寫入原樣品，因此是具有可消除與可覆寫可調控特性之雷射元件，此元件之功能凌駕於過去所研究過可空間調控元件之上。

This thesis studies the gradient-radiation-induced spatially-tunable lasing emissions based on dye-doped cholesteric liquid crystal (DDCLC) films with a photochromatic chiral dopant. With continuously changing the irradiated position in the cell, the concentration of the cis-isomers of the photochromatic chiral dopant (AzoM) via transcis isomerization and thus the pitch of the cell can be continuously varied; in turn, the spatially-tunable lasing emission can be obtained. The maximum range of the wavelength-tunability for the obtained laser devices in this study is ~134 nm.
Such a feature of the spatially-tunable lasing wavelength of the cell can be totally eased rapidly by the uniform illumination of a green beam and slowly by the thermal effect, respectively. After erased, the spatially-tunable feature can be re-recorded in the original cell using the same method. Thus, such a laser device is more flexible than those fabricated in the past, which spatially-tunability is not erasable and re-recordable.

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