對於一個製程昂貴的光學薄膜元件來說,更為精緻和精確的監控是必要的。本文提出了一個新的監控方法,藉由薄膜光學理論的數學的推演分析,找出不同膜堆的最佳監控波長,並計算出每層膜厚對中心波長的厚度補償。此方法兼具了高靈敏度的監控效果和保持中心波長不偏移的優點。模擬結果證明,以此法監控所製鍍而成的光學濾片,其成效明顯比用傳統的極值點監控法所製鍍者優良。 For a costly optical element production, more precise monitor method is necessary. A finer monitor method is proposed. Based on numerical analysis, the most sensitive monitor wavelength is clearly found out, and the thickness compensation for central wavelength is calculated. This method not only can cut layers precisely, but also keep the central wavelength in the right position. It is shown that the performance of optical thin film element monitored by this new method is much better than by the turning point method in coating process.