近红外大数值孔径平场显微物镜设计  

Design of high NA flat-field microscope objective for near infrared

作　　者：周恩源[1] 刘丽辉[1] 刘岩[1] 曹振[1] 

机构地区：[1]北京理工大学光电学院光电成像技术与系统教育部重点实验室,北京100081

出　　处：《红外与激光工程》2017年第7期180-186,共7页Infrared and Laser Engineering

基　　金：国家自然科学基金(61435005)

摘　　要：为满足飞秒激光微纳加工系统对高加工精度和大加工范围的需求,首先确定了该系统的重要组成部分-无限共轭距显微物镜所需具备的特性及设计指标。依据薄透镜组的初级像差理论,针对飞秒激光波长推导出光学系统为校正匹兹凡场曲和二级光谱所需满足的条件。该镜头由11片球面透镜构成,所选用材料皆为国产玻璃,同时避免三胶合结构的使用。设计了一套工作波长为785~815 nm,数值孔径为0.9,像方视场为22.5 mm,放大倍率为40×的近红外平场复消色差显微物镜。设计结果表明:该镜头的MTF良好,全视场波像差均小于0.08λ,各种几何像差均远小于公差且满足平场和复消色差条件,能量集中度高。使用补偿器放松材料公差、加工公差和装调公差,公差分配后全视场RMS波像差小于0.09λ,满足实际应用要求。To meet the requirements of femtosecond laser micro-nanofabrication systems for highprecision and wide region, the features and design specifications of infinity microscope objectives whichwere important components of the systems were determined. Based on the theory of primary aberration ofthin lens system, the conditions to meet were concluded to correct Petzval curvature and second orderspectrum for femtosecond wavelength. The objective consisted of 11 spherical lens, and all materials wereglass made in China, and the use of cemented lens composed of three lens was avoided. A near infraredflat-field microscope objective, whose working wavelength was 785-815 nm, numerical aperture was 0.9,field of view in image space was 22.5 mm, magnification was 40x, was designed. Designing results showthat the objective has excellent MTF, RMS wavefront errors of all fields are less than 0.08A, and variousgeometrical aberrations are deeply under tolerances, the results meet the conditions of flat field andapochromatism, and energy concentration is high. Compensators are used to slacken material tolerance,manufacturing tolerances and alignment tolerances. RMS wavefront errors of all fields get less than 0.09Aafter tolerances attribution and the objective can be applied actually.

关 键 词：光学设计 显微物镜 平场 飞秒激光 微纳加工 

分 类 号：TH703[机械工程—仪器科学与技术]