用于高功率激光放大器的单层宽谱增透膜

摘要

为了获得用于高功率激光放大器的单层宽带增透膜,采用有机聚合物聚乙烯吡咯烷酮掺杂调控二氧化硅胶体生长制备了粒度分布更宽广的稳定胶体体系,通过提拉镀膜工艺,制备了单层增透膜. 采用粒度仪和粘度仪监测胶体的性质,用分光光度计测量了膜层透过率,并用X射线能谱分析了膜层结构. 结果表明,聚乙烯吡咯烷酮引入胶体中使得胶体粒度分布更宽,所得膜层具有折射率渐变特性,因而膜层具有宽带增透的效果;膜层在550nm~950nm连续波段内透射率不低于99%. 单层宽谱增透膜层不需后处理就可投入使用,膜层性能稳定,满足了激光装置片状放大器的运行要求.%In order to obtain broadband antireflective single layer coating for high power laser amplifiers , stabilized SiO2 sol system with more widely particle size distribution was prepared from silica sol doped and regulated by organic polymer polyvinylpyrrolidone ( PVP ) . Single-layer broadband antireflective coating was developed by sol-gel dipping method . The properties of sol were measured by nanoparticle analyzer and viscometer , the transmittance was measured by spectrophotometer and the coating structure was measured by X-ray spectrometer .The results indicate that the introduction of PVP into silica sol leads to wider distribution of silica sol particles , which makes the coatings have the graded characteristics of refractive index . Thus the coating is broadband and antireflective .The inside transmittance of coatings is higher than 99%in the 550nm~950nm. The single-layer broadband antireflection coating has the stable film performance and can be put to use without post -processing . The single-layer anti-refractive coating meets the requirement of high power laser amplifiers .