本論文為研究利用生物環保材料chitosan製成窄帶濾光片，首先利用Macleod軟體找出此種材料之n、k值，進而設計在可見光波段之窄帶。實驗中利用磁控濺鍍方法鍍製第一層Ag後，接著在Ag層上塗佈chitosan，利用不同轉速控制chitosan層的厚度，接著再鍍上一層Ag，樣品完成後即進行光譜量測並與原先的設計進行比較與分析。 由於chitosan有著良好的吸濕性，藉由放置在不同的濕度環境下，量測光譜後觀察其波峰偏移的情形，再利用Macleod軟體推算樣品的折射率變化及厚度變化，最後再計算靈敏度。 ;In this research, we design and make a narrow-band pass filter by using chitosan, an environment-friendly material as a spacer. Macleod software is used to find out the refractive index and extinction coefficient of the material, and then design narrow-band pass filters in visible light band. First, Ag film was deposited on a substrate by magnetron sputtering. Second, chitosan was spin-coated on the Ag layer. Last, Ag film was deposited on the chitosan layer. The thickness of the chitosan layer was controlled by different rotational speed. After the sample was completed, we compared with the original design and do the analysis. Chitosan is hygroscopic, so we placing the sample in different humidity environment and measuring the redshift. And then we calculate the changes of refractive index, thickness and sensitivity of chitosan.