傳統全像儲存架構在進行多工記錄時，會隨著記錄頁數的增加，讀取時的繞射效率呈平方倍數下降。在讀寫過程中，各軌道的間距會受到記錄頁數的限制，導致在同樣範圍內能記錄的資訊量減少。此外，頁與頁之間的串音限制使得頁面間距不能太近，而過大的頁面間距會大幅增加馬達的轉矩。不僅如此，系統對於讀取位置的靈敏度要求極高，必須非常接近寫入位置才能讀取出資訊，因此在機械限制下，要達到高速且精準的讀取過程是非常困難的。 本論文提出的全像儲存系統克服了上述所提到的問題，通過改變傳統記錄和讀取的方式，不僅改善了多工記錄繞射效率受到M/#限制的情況，還改善了系統對於讀取位置高靈敏度的要求。此系統將多頁的資訊記錄在同一記錄區域中，並透過設計各組光柵的訊號光相位，得到位移疊加讀取的訊號，在不同位置下的干涉結果。 ;In traditional holographic storage systems, the diffraction efficiency during readout decreases exponentially as the number of recorded pages increases. The spacing between tracks during the read-write process is constrained by the number of recorded pages, which reduces the amount of information that can be stored within the same area. Furthermore, crosstalk between pages restricts how close the pages can be, while excessively large page spacing significantly increases the motor′s torque. Additionally, the system requires extremely high sensitivity to the readout position, necessitating very close proximity to the write position to retrieve information. Therefore, achieving high-speed and precise readout processes is extremely challenging under mechanical constraints. This thesis proposes a holographic storage system that overcomes the aforementioned issues. By altering the traditional recording and readout methods, this system not only improves the diffraction efficiency of multiplexed recordings, which is limited by the M/#, but also reduces the system′s sensitivity to the readout position. This system records multiple pages of information within the same recording area and, by designing the signal light phases of each set of gratings, achieves displacement-added readout signals, resulting in interference at different positions.
