目的 采用热蒸发沉积技术制备可用于人脸部识别的850 nm滤光片，研究滤光片的激光损伤阈值以及薄膜内部的电场分布。方法 采用TFC膜系仿真设计软件完成850 nm滤光片的设计与优化。采用真空箱式镀膜机，通过增加挡板、调整监控波长，以离子束辅助热蒸发沉积技术完成滤光片的制备。结果 通过紫外-红外分光光度计实现了在中心波长透射率为83.05%、其他波段T<5%的光谱特性测试。采用R-on-1的激光损伤测试方法得到TiO2/SiO2组合滤光片的激光损伤阈值达4.2 J/cm2，ZnS/MgF2组合滤光片为2.8 J/cm2。TiO2/SiO2组合滤光片空气-薄膜界面电场强度为0.3474，ZnS/MgF2组合滤光片为0.9357。分析显微镜下的微观结构得到，相比TiO2/SiO2组合，同一能量下，ZnS/MgF2组合的薄膜激光损伤斑较大，易出现损伤。结论 可以通过增加挡板、调整监控波长的方式实现窄带滤光片的制备。为了更好地获得激光损伤阈值较高的滤光片薄膜，在设计滤光片时尽可能地降低薄膜与空气界面处的电场分布，即界面处电场强度分布越小，薄膜表面抗激光损伤的能力越强。同时发现TiO2/SiO2组合滤光片激光损伤阈值大于ZnS/MgF2组合滤光片。

The paper aims to prepare 850 nm filter that can be used for face recognition by thermal evaporation deposition technique to study the laser damage threshold of the filter and the electric field distribution inside the film. The design and optimization of the 850nm filter was completed by the TFC film system simulation design software. The vacuum box coating machine was used to prepare the filter by adding baffles, adjusting the monitoring wavelength and ion beam assisted thermal evaporation deposition technology. The spectral characteristics of the center wavelength transmittance of 83.05% and the other wavelength bands of T<5% were achieved by the ultraviolet-infrared spectrophotometer test. The laser damage threshold of TiO2/SiO2 combination filter obtained by R-on-1 laser damage test method reached 4.2 J/cm2; and that of ZnS/MgF2 combination filter was 2.8 J/cm2. The air-film interface electric field strength of the TiO2/SiO2 combination filter was 0.3474; and that of the ZnS/MgF2 combination filter was 0.9357. From the microstructure under the microscope, it was found that the ZnS/MgF2 combination film had a larger laser damage spot and was more susceptible to damage than the TiO2/SiO2 combination under the same energy. The narrow band filter can be prepared by adding a baffle and adjusting the monitoring wavelength. In order to obtain a filter film with a higher laser damage threshold, the electric field distribution at the interface between the film and the air is reduced as much as possible when designing the filter, that is, the smaller the electric field intensity distribution at the interface, the more powerful the surface of the film in resistant to laser damage. At the same time, it is found that the laser damage threshold of TiO2/SiO2 combination filter is larger than that of ZnS/MgF2 combination filter.