基于傅里叶变换合成法的基本原理, 合成了一个K9基底上的负滤光片, 合成的渐变折射率薄膜具有期望光学特性, 但实际制备难度很大, 因此将其细分为足够多层离散折射率的均匀薄膜, 由于实际薄膜材料种类有限, 不能获得任意折射率膜层, 鉴于两层高低折射率薄层可近似为一层中间折射率膜层的思想, 将膜系转化成一个可实际制备的膜系结构：膜系采用ZrO2和SiO2两种膜料, 膜层总数为183层, 经单纯形调法优化后, 膜层总厚度为7.09 μm, 通带和截止带内平均透射比分别为97.56%和3.13%, 其结果优于直接采用傅里叶方法合成的非均匀膜系, 与期望透射比曲线吻合更好。说明通过这种思想设计任意光谱特性的膜系是可行的, 也使傅里叶变换合成法设计的薄膜实际制备成为可能。

Based on the theory of Fourier-transform synthesis method, a minus filter on K9 substrate was synthesized. The gradient-index thin film with the desired transmittance character was synthesized by Fourier-transform synthesis method, but it is difficult to fabricate. So it was divided into many homogeneous coatings with discrete refractive index. For the limited kinds of coating material, the thin film with arbitrary refractive index is not available. Based on the idea of two very thin high-low pair layers can be treated approximately as a thin layer with an average refractive index of the two layers, these coatings were replaced by homogeneous coatings. After optimization of simplex-law, the layers are composed by 183 layers of ZrO2 and SiO2. And the total thickness is 7.09 μm. The average transmittances in pass band and rejection band are 97.56% and 3.13%, respectively. And the optimizated result is better than that made with ununiform coatings and concides with the desired one. All these indicate that it is a feasible method to design coatings with any desired spectrum character, and it is possible to fabricate the coatings designed with Fourier-transform synthesis method in practice.