用液芯变焦柱透镜精确测量液体折射率  

Refractive Index of Liquid Measured by Liquid-Core Zoom Cylindrical Lens

作　　者：李强[1] 孙丽存[1] 孟伟东[1] 普小云[1] 

机构地区：[1]云南大学物理科学技术学院物理系,云南昆明650091

出　　处：《中国激光》2012年第10期162-168,共7页Chinese Journal of Lasers

基　　金：国家自然科学基金(11164033);云南省应用基础研究基金(2011FA006);云南省高校科技创新团队支持计划资助课题

摘　　要：加工制作了一种液芯变焦柱透镜,并利用这种柱透镜精确测量液体的折射率。在空心的柱透镜内注入待测液体,通过测量液芯透镜的焦距,根据焦距和折射率之间的关系,计算出液芯介质的折射率。此方法有效地提高了折射率测量的灵敏度,减小了测量系统的景深。选取20×显微物镜可实现液体折射率在1.3～1.642范围内的精确测量,单次测量误差小于0.0002。对透镜折射率灵敏度曲线以及测量系统景深曲线的分析表明,增加折射率灵敏度和测量系统的有效数值孔径,可以进一步提高测量的准确度。A liquid-core-zoom cylindrical lens has been fabricated,which is used to measure accurately the refractive index of liquid filled into the core region of the cylindrical lens.The focal length of such a cylindrical lens varies with the refractive index of core liquid,which can be known by measuring experimentally the related focal length.Due to a high sensitivity in measuring refractive index and a short depth of field,a high accuracy in measurement of refractive index is ensured.The accuracy of refractive index for one single measurement is better than 0.0002 in the range of 1.3~1.642,when a 20× objective is used in a reading microscope.By either enhancing sensitivity of refractive index of the cylindrical lens or enlarging effective numerical aperture of the measurement system,the accuracy of refractive index can be further improved.

关 键 词：测量 液体折射率 测量灵敏度 柱透镜 景深 

分 类 号：O439[机械工程—光学工程] TN247[理学—光学]