體積全像術在光學資訊儲存之研究

Abstract

本論文主要內容在探討體積型全像光學儲存系統中的光折變晶體之晶軸方 向、 耦合常數及記錄光束之強度比等儲存條件對繞射效率的影 響，以求取全像光學 資訊儲存的最佳條件，並以實驗驗證之。 我們首先利用耦合波理論推導繞射效 率與儲存參數之間的關係 式，並用電腦作模擬計算與分析；然後，根據理論上 的分析與 討論，再設計光學實驗以驗證之。最後，我們建立一個多工儲存系 統，並利用旋轉多工 ( peristrophic mutiplexing ) 的方法儲存多張影 像於鈮酸鋰晶 體及光感聚合物兩種記錄介質中。 In this thesis, we present our theoretical and experimental investigations on diffraction properties of transmission-type photorefractive gratings with nonreciprocal coupling effect. By using the coupled-recording-wave approach, the diffraction efficiency is derived as a function of the direction of the crystal c-axis, the coupling constant, and the intensity ratio of the two writing beams. We then demonstrate our computer simulation and optical experimental results. According to these results, we can find out the optimum conditions for holographic storage systems using PR crystals. Finally, we design and construct a holographic storage system by using peristrophic-mutiplexing technique. Ninety images have been stored in a LiNbO3 crystal and ten images have been stored in a photopolymer film.