隨著網路普及的時代下，資訊安全已成為人們不可忽略的重要議題。為了防止資訊被一人獨佔，如何分享秘密訊息給參與者將是很重要的議題。透過(k,n)門檻的技巧得知，我們把秘密資訊分散在n張子影像，並由n個參與者保管。只要任意收集k張或以上的子影像，便可還原我們的原始資訊。反之，少於k張子影像則無法獲得足夠的資訊來還原秘密影像。
在此篇論文中，我們經由分析Ulutas [Ulut2009]的方法及熟悉中國餘式定理後，提出一個新方法來實作影像分享及還原系統。跟其他方法相比，此篇的方法較精簡之外，也能確保原本的秘密影像不會造成失真。如此一來除了確保祕密資訊不被外人洩漏外，也能保留資訊完整性。

According to the success of the Internet, Information security becomes an important issue to the human beings. To avoid the information is carried by only a single individual, how to share the secret information to the participants would be an important subject. According to the (k,n)-threshold scheme, the data are partitioned into n shadows which are distributed to n participants. By collecting at least k out of n shadows, we can completely recover the original data. Otherwise, we could not recover the original data.
We propose a new method to improve the implementation method of Ulutas [Ulut2009] based on Chinese remainder theorem in this thesis. The advantage of our method in this thesis is that we not only simplify the method, but also guarantee the recovered image would not get distorted. Experiments for three color images are provided for demonstration.

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