此研究之目的為減少全像儲存系統中像差所產生的誤碼，使用錯誤訂正碼中的RS碼能有效解決隨機雜訊，還原圖形時加入灰階權重法，解決使用人工定位方式所造成的大量誤碼。使用灰階權重法後，RS碼可完全訂正還原編碼頁面中的誤碼，得到沒有誤碼的解碼圖。
當光學系統存在失焦或透鏡像差較嚴重時，灰階權重法亦能有效降低誤碼數，可知灰階權重法降低了全像儲存系統對於光學品質的需求。利用高斯累加機率圖求得平均數與標準差，畫出與實驗之灰階分佈吻合的高斯分佈曲線，計算出還原圖形誤碼率的理論值，使用立景LCoS與普通透鏡時得到最佳誤碼率之理論值4.19×10^-10。

The purpose in this study is to reduce the error bits caused in the holographic data storage system, and use the RS code of error correction codes to slove the random noise effectively. After using the gray level weighting method, RS code can correct all error bits of reduced coding pages, and get decoded figure without error bits.
The gray level weighting method can decrease error bits effectively when optical system has defocus aberration or more serious lens aberration. We can know that using the gray level weighting method can decrease the optical demand of holographic data storage. Utilize Gaussian accumulate probability to get the mean value and standard deviation to describe the Gaussian destribution curve matched the gray level distribution of actual experiment. Calculate the theoretical value of bit error rate of reduced figure. Using the Himax LCoS and common lens to get the optimal theoretical value of Bit Error Rate is 4.19×10^-10。

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