具有偶氮苯環結構的旋性物質Ql-3c-S，在照射紫外光後，會由棒狀的trans態轉變為同分異構物的彎曲狀cis態，兩種狀態對向列型液晶的Helical twisting power(簡稱HTP)不同，cis態的HTP比trans態的HTP值小，所以摻雜Ql-3c-S的膽固醇液晶樣品在照射紫外光時，螺距(pitch)會變大。由於受到遮蔽效應，隨樣品深度不同會有不同紫外光的強度，所以在照射紫外光時，不同樣品深度的cis 態濃度變化會不同，導致照光面上螺距會比未照光面螺距大，導致螺距會有類似梯度變化的效果。
我們利用光啟始劑Irgacure 651 使高分子RM257在紫外光下聚合的特性。將光啟始劑Irgacure 651、高分子RM257依據本實驗最佳比例混合於摻雜Ql-3c-S的膽固醇液晶，照射紫外光後，利用聚合的高分子網狀結構穩固其螺距變化，因此所製成的Polymer-stabilized Cholesteric Texture(簡稱PSCT)，會有類似螺距成梯度變化的效果，亦即膽固醇液晶反射頻譜增寬的現象產生。
本論文中為了產生較大的反射頻寬，分別改變了Ql-3c-S及高分子等的濃度，並改變外在因素如溫度、照射時間和液晶盒厚度等，觀察上述參數造成反射頻譜的大小變化。而利用最佳參數所製成PSCT的最大反射頻寬可高達約275 nm。

Ql-3c-S is an azo chiral material. If we irradiate a cholesteric liquid crystals doped with Ql-3c-S with UV light, the rod-like trans-isomers will be switched to the bend-shaped cis-isomers. Since the HTP (Helical Twisting Power) of trans-isomers differs from that of cis-isomers, the pitch length of azo chiral-doped cholesteric liquid crystals increases with the UV light irradiating on. Also, the pitch length at the front side of sample facing the UV light is longer than that in the rear side. As a result, the there forms a gradient-like pitch distribution, and the reflection band of a planar sample becomes broadened.
In this study, we add a photo-initiator Irgacure 651 and a monomer RM 257 in a Ql-3c-S doped cholesteric sample and irradiate it with UV light. The formed polymer network structure will stabilize the sample, forming a polymer-stabilized cholesteric texture (PSCT) sample with a broad–band reflection spectrum.
In order to maximize the reflection spectrum, we performed experiments with the sample having different concentrations of Ql-3c-S and Monomer. Moreover, we changed various sample fabrication parameters such as the temperature, curing time, cell gap. Using the optimizing condition, we can fabricate a planar PSCT having a reflection bandwidth of approximate 275 nm.

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