雙隨機相位編碼於數位全像加密之研究

A study on digital holographic encryption using double random phase masks

周進文(Jin-Wen Chou)

指導教授 ： 吳俊傑 ； 鄭超仁

國立臺北科技大學/電資學院/光電工程系研究所/碩士(2009年)

摘要

在本論文中，我們探討雙隨機相位編碼的特性，並將其應用於數位全像加密。首先，研究隨機相位編碼的特性及其數位全像的加密方式，並進一步地利用雙隨機相位編碼於全相位式數位全像加密方式，探討其理論架構及相關特性。在數值模擬方面，我們驗證了此加密方式的可行性，並且分析輸入影像的相位編碼方式及隨機相位編碼的特性。接著，我們探討了液晶空間光調制器實現隨機相位編碼的可行性，並透過調制範圍的選定以獲得類似於隨機相位編碼的調制特性。在光學實驗方面，我們架設了全相位式數位全像加密系統以進行相關的二位元影像加密實驗。 最後，我們利用液晶空間光調制器實現線上可程控的全相位式數位全像加密方式，並透過輸入隨機相位編碼圖形的不同，可以改變隨機相位編碼的特性，以獲得較佳的實驗結果。內文中將提出相關模擬與實驗結果，並加以分析與說明。

關鍵字

數位全像術 ； 全相位式加密 ； 雙隨機相位編碼 ； 液晶空間光調制器

並列摘要

In this study, we investigation the properties of double random phase encoding and its application on digital holographic encryption and key mask design. Firstly, we study the properties of the double random phase mask and digital holographic encryption approaches. Then, we propose and demonstrate a new full phase digital holographic encryption approach using double random phase key masks. This proposed encryption approach is executed by phase-encoding input images with double random phase masks. Furthermore, the possibility of the random phase mask using the liquid crystal spatial light modulator is investigated and analyzed. Selecting the appropriate modulation range, we can obtain the phase variation property similar to random phase mask for optical implementation. Further, we construct a full phase digital holographic encryption system to experimentally verify the validity of the approach with the input binary image. Finally, an on-line programmable full phase digital holographic encryption system based on the liquid crystal spatial light modulator is experimentally demonstrated. Both simulated and experimental results are presented and discussed, which are correctly proved and satisfactory.

並列關鍵字

Digital holography ； Full phase encryption ； Double random phase mask ； Liquid crystal spatial light modulators

參考文獻

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[4] Enrique Tajahuerce and Bahram Javidi, "Encrypting three-dimensional information with digital holography," Appl. Opt., 39, 6595-6601 (2000).

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