为满足探测1，2丙二醇二硝酸脂有毒气体浓度的红外探测元件抑制带截止深度深、通带内平均透射比高、波纹系数小等要求，采用等效折射率理论与局部优化相结合的设计方法，选用PbTe/ZnSe作为高低折射材料，采用长波通膜系、短波通膜系以及双半波膜系设计了截止深度深、双通道、通带宽度合适的红外滤光片，通带分别为5.9～6.2 μm及11.9～12.2 μm，通带内平均透射比分别在90%及65%以上；对所设计的膜系进行了薄膜物理厚度和膜层折射率的误差分析。分析表明，薄膜制备时沉积速率精度应控制在3.5%以内，材料折射率的变化应控制在3%以内，与膜层折射率相比，薄膜物理厚度对平均透射比的影响小，并且双半波膜系对厚度以及折射率变化更敏感。

In order to meet the requirements of high transmittance in pass bands, high reflectance in rejection bands, small ripple coefficient for detecting 1, 2-propanediol dinitrate with infrared detector cell, an infrared dual-channel band pass filter with proper rejection band has been designed using the combined method of the Herpin refractive index principle and local optimization, as well as choosing PbTe/ZnSe as the material of high/low refractive index. A dual channel filter with pass bands of 5.9～6.2 μm and 11.9～12.2 μm and the average transmittance exceeds 90% and 65% respectively was designed. An error analysis of layer physical thickness and refractive index has been done for the design, which shows that the precision of deposition rate should be controlled within 3.5%, meanwhile, the refractive index accuracy should be lower than 3%, the refractive index has greater effect on the reflectance than the thickness, and the double half-wave film is more sensitive in the changes of refractive index and the thickness.