本研究發現利用將藍相液晶灌入楔形樣品可產生具有廣波段的可空間調控反射可見光。因藍相液晶可以反射可見波長的光，而且隨著降溫此反射頻譜會有明顯的紅移現象，因此藉由楔形結構具有的厚度梯度變化產生一連續變化的藍相液晶反射頻譜。由於不同的厚度會提供不同的邊界錨定影響力，進而嚴重影響藍相液晶反射頻譜的紅移現象。此藍相液晶反射頻譜總共連續調控了超過130奈米距離，幾乎接近全白光範圍。此外，本研究更進一步研發出利用楔形結構產生藍相液晶調控雷射輸出，其雷射輸出波長在反射頻譜範圍內連續調控將近70奈米距離。值得注意的是，利用楔形結構產生的藍相液晶反射頻譜調控範圍和雷射輸出調控範圍遠遠超過利用膽固醇相液晶於楔形結構的反射頻譜和雷射輸出的調控範圍。如此可空間上大範圍調控的藍相液晶反射頻譜跟雷射輸出在光電領域上擁有很大的潛力，未來可應用於光電元件與顯示上。

This study demonstrates a spatially tunable reflection of wide spectral range based on blue phase liquid crystal (BPLC) in a wedge cell. Blue phases (BPs) show reflection of light in the visible wavelength and have obvious red-shifting phenomenon during the cooling process. Therefore, the continuously shifting reflections of BPLC wedge cell is occurred by means of the gradient thickness in wedge cell. The gradient thickness of wedge cell provides different surface anchoring force to limit the red-shifting effect of reflection of BP. Due to gradient surface anchoring force within the wedge cell, the continuously shifting reflection is even more than 130 nm nearly covering the range of blue, green, red light. Also, the spatially tunable lasing emissions based on dye-doped blue phase liquid crystal (DDBPLC) in wedge cell is demonstrated and the lasing wavelength is continuously tuned in the region of the shifting range of reflection of BP. The shifting range of lasing emissions is about 70 nm. Both the two shifting ranges (reflections and lasing emission) are extremely larger than the shifting range in CLCs wedge cell. The shifting reflection and lasing emissions of BP have a great amount of potential in applications of optoelectronic device and display.

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