复合型透射式脉冲压缩光栅的设计与制作  

Design and fabrication of a composite transmission pulse compression grating

作　　者：李朝明[1] 陈新荣[1] 李林[1] 虞健[1] 吴建宏[1] 常增虎[2] 

机构地区：[1]苏州大学物理与光电.能源学部与苏州纳米科技协同创新中心苏州大学江苏省先进光学制造技术重点实验室和教育部现代光学技术重点实验室,江苏苏州215006 [2]中佛罗里达大学光学-激光研究与教育中心,佛罗里达32816

出　　处：《光学精密工程》2016年第12期2983-2987,共5页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.60808013;No.61178046);江苏省高校自然科学研究重大项目(No.11KJA140001);江苏省高校优势学科建设工程资助项目

摘　　要：提出了一种用于飞秒钛宝石激光器的复合型透射式脉冲压缩光栅。该光栅由1 250line/mm和3 300line/mm两种光栅集成在一个熔石英基底上制成,其工作中心波长为800nm,工作波段为700~900nm。1 250line/mm光栅用于脉冲压缩;3 300line/mm光栅的运用则有益于减少透射光栅的反射损失,同时由于采用高频光栅结构代替了传统增透膜,可有效减少光栅基底的波前形变。该复合光栅完全由熔石英材料构成,故具有很高的损伤阈值。利用严格耦合波理论对该复合型透射光栅的微结构进行了优化设计,结果表明:1 250line/mm光栅在中心波长800nm处的-1级衍射效率可达98%;3 300line/mm增透光栅的透过率在700~900nm波段可以达到99.7%以上。最后,应用全息记录技术和离子刻蚀技术实际制备了Φ65mm×1mm的复合式透射脉冲压缩光栅,实测衍射效率与理论设计相符。A composite transmission pulse compression grating was proposed for femto-second Ti ＂ sapphire la- sers. The composite transmission grating with 700--900 nm bandwidth worked at a center wavelength of 800 nm was consisted of two gratings with groove densities 1 250 line/ram and 3 300 line/mm and they were integrated in a fused silica plate. The 1 250 line/ram grating was used for compressing laser pulse. The 3 300 line/ram anti- reflection grating was conductive to decreasing the reflection loss and avoiding the wave-front distortion by using a high frequency grating structure to replace the anti-reflection film on the surface oi the Iusea sllma plato, vxm^- pletely being made of fused silica, the composite pulse compression grating has a high laser damage threshold. The composite transmission grating was designed based on the rigorous coupled wave theory. The optimization caleulation results show that the --lst order diffraction efficiency of the 1 250 line/ram grating is up to 98% （@ 800 nm） and the transmission of the 3 300 lp/mm grating is up to 99.7% at 700--900 nm bandwidth. Finally, the composite transmission pulse compression grating（Ф65 mm× 1 mm） was fabricated by holographic recording and ion bean etching and its diffraction efficiency is co＇incident with that of the theoretical analysis.

关 键 词：脉冲压缩光栅 熔石英透射光栅 衍射效率 激光损伤阈值 

分 类 号：O436.1[机械工程—光学工程]