目的 研究多波段全介质高反射薄膜的光谱性能、应力特性以及膜层的抗激光损伤性能，获取应力状态良好的大口径薄膜样片。方法 选用TiO2、SiO2高低折射率材料，设计并制备500~650 nm、780~830 nm、1 050~1 080 nm 3波段兼容的介质高反膜。研究单层膜工艺参数，监控波长为560 nm，基于电场强度分布，膜系结构优化为G/(HL)⁸H(2L)⁴ (1.4H1.4L)⁸H2L(1.9H1.9L)⁸1.9 H/A。在不同膜堆之间添加低折射率层来抑制虚设问题，平滑反射光谱，通过离子束辅助电子束蒸发技术在?220 mm的大口径基底上成功制备出性能良好的宽波段大尺寸多层高反射薄膜。结果 其反射光谱在可见光500~650 nm波段范围内，平均反射率为99.5%，峰值反射率为99.9%，最低反射率为95.1%;在780~830 nm波段内，峰值反射率为99.9%，平均反射率为99.8%，最低反射率为99.6%;在1 050~1 080 nm波段内，其平均反射率能够达到99.8%，峰值反射率达到99.9%，最低反射率达到99.7%。大口径薄膜样片不同位置的反射光谱一致性较高。膜层的抗激光损伤阈值为7.1 J/cm²，残余应力为–293.59 MPa。结论 大口径薄膜样片膜厚均匀性良好，成膜致密，无起皱、龟裂、脱落等现象出现，膜层牢固性较高，具备优良的激光防护性能。

This paper aims to select TiO2 and SiO2 high and low refractive index materials, design and prepare 500~650 nm, 780~830 nm, 1 050~1 080 nm three-band compatible dielectric high reflective films. The spectral properties, stress characteristics and laser damage resistance of high reflective films composed entirely of dielectric materials for multi-band application are studied, and the large aperture film samples with good stress state are obtained. The process parameters of monolayer films were studied, with the monitoring wavelength 560 nm, based on the electric field intensity distribution, and film structure was optimized to be G/(HL)8H(2L)4 (1.4H1.4L)8H2L(1.9H1.9L)81.9 H/A. Low refractive index layers were added between different film stacks to suppress the nominal problem, and the reflectance spectral was smoothed, wide-band large-size multilayer high reflective film with good performance was successfully prepared on a large aperture substrate of ф220 mm by ion beam assisted electron beam evaporation technology. Its reflectance spectral was in the visible light range of 500~650 nm, with the average reflectivity of 99.5%, the peak reflectivity of 99.9%, the minimum reflectivity was 95.1%; within the scope of 780~830 nm, the peak reflectivity was 99.9%, and the average reflectivity was 99.8%, and the minimum reflectivity was 99.6%; in the 1 050~1 080 nm band, its average reflectivity could reach 99.8%, and the peak reflectivity reached 99.9%, and the minimum reflectivity reached 99.7%; reflectance spectral of large aperture film sample at different positions were high consistent. The laser-induced damage threshold of film was 7.1 J/cm2, and the residual stress was –293.59 MPa. The film thickness uniformity of large aperture film sample is good, and the film is compact without wrinkle, crack and falling off phenomena, with higher fastness and excellent laser protection performance.