Design of dispersive objective lens of large linear chromatic confocal 3D surface profiler
-
摘要: 光谱共焦三维形貌仪具有精度高、测量范围大、适应性强等特点,其关键部件是产生轴向色散的物镜,色散物镜轴向色散与波长间的非线性会导致系统整体性能下降。分析了共焦法检测表面形貌的工作原理,以及产生线性轴向色散的条件,根据共焦光学系统的基本设计原理,在预设的设计指标及要求下,完成一个超大色散线性物镜组设计。该色散物镜组采用四级串联结构,在400~700 nm光谱范围内达到30 mm的色散范围,波长离焦量和波长之间线性度通过线性回归拟合得出判定系数为1,满足色散的线性度要求。Abstract: Chromatic confocal 3D profiler has high precision, large measuring range and strong adaptability. The key component is the objective lens with axial dispersion. The nonlinear dispersion of axial dispersion and wavelength of the dispersion objective lens reduces the overall performance of theprofiler. In this paper, by analyzing the principle of confocal method to detect surface topography and the conditions for producing linear axial dispersion, the design indexes and requirements of confocal optical system are given, and a super-dispersive objective lens has been designed.The objective lens has four magnification structures in series dispersing the focus of wavelength between 400 and 700 nm to 30 mm longitudinal range. Through linear regression fitting of the defocusing amount and linearity of the wavelength, it is obtained that the coefficient of determination is 1, greatly improving the linearity of dispersion.
-
Key words:
- chromatic confocal /
- dispersive objective lens /
- surface profile /
- linear dispersion /
- optical design
-
表 1 色散物镜结构参数
Table 1. Structure parameters of dispersive objective lens
radius of curvature/mm thickness/mm material radius/mm 152 6.273 317 H-ZF72A 7.626 787 -181 5.791 638 H-ZK21 8.168 694 -27 14.145 228 8.629 423 22 5.683 613 H-ZLAF92 7.975 332 11 6.994 287 H-FK71 6.685 219 -50 104.400 962 6.464 555 73 6.901 395 H-FK71 8.668 252 -12 7.201 105 H-ZLAF92 8.820 381 -28 1.495 814 11.412 310 25 4.340 051 H-ZK21 12.668 725 153 4.005 912 H-ZF72A 12.488 838 infinity 98.394 688 12.075 799 211 3.970 081 H-ZF72A 12.356 620 -262 3.946 532 H-ZK21 12.645 284 -28 1.796 616 12.765 914 20 4.787 852 H-ZLAF92 11.400 054 11 6.999 160 H-FK71 8.985 674 -68 90.044 451 8.819 089 60 6.731 128 H-ZPKS 9.344 148 -11 5.331 079 H-ZLAF78B 9.402 357 -21 17.349 091 11.348 517 36 6.998 568 D-K59 10.712 105 12 4.354 659 H-LAF10LA 9.481 764 25 58.835 809 9.079 874 -
[1] 李海燕. 多功能共焦表面测量系统研究[D]. 哈尔滨: 哈尔滨工业大学, 2009.Li Haiyan. Study of the multi-functional confocal measurement system. Harbin: Harbin Institute of Technology, 2009 [2] Minsky M. Microscopy apparatus[P]. US 3, 013, 467, 1961-12. [3] Courtney-Pratt J S. The use of our specially designed monochromatic microscope objective to examine tracks in nuclear emulsions[J]. Opt Eng, 1976(15): 379-383. [4] Molesini G, Pedrini G, Poggi P, et al. Focus-wavelength encoded optical profilometer[J]. Optics Communication, 1984, 49(4): 229-223. [5] 朱万彬, 钟俊, 莫仁芸, 等. 光谱共焦位移传感器物镜设计[J]. 光电工程, 2010, 37(8): 62-66. https://www.cnki.com.cn/Article/CJFDTOTAL-GDGC201008015.htmZhu Wanbin, Zhong Jun, Mo Renyun, et al. Design of spectral confocal chromatic displacement sensor objective. Opto-Electronic Engineering, 2010, 37(8): 62-66 https://www.cnki.com.cn/Article/CJFDTOTAL-GDGC201008015.htm [6] 王津楠, 陈凤东, 刘炳国, 等. 基于白光LED的光谱共焦位移传感器[J]. 中国测试, 2017, 43(1): 69-73. https://www.cnki.com.cn/Article/CJFDTOTAL-SYCS201701015.htmWang Jinnan, Chen Fengdong, Liu Bingguo, et al. White LED-based spectrum confocal displacement sensor. China Measurement & Test, 2017, 43(1): 69-73 https://www.cnki.com.cn/Article/CJFDTOTAL-SYCS201701015.htm [7] 刘乾, 王洋, 杨维川, 等. 线性色散设计的光谱共焦测量技术[J]. 强激光与粒子束, 2014, 26: 051010. doi: 10.11884/HPLPB201426.051010Liu Qian, Wang Yang, Yang Weichuan, et al. Chromatic confocal microscope with linear dispersive objective. High Power Laser and Particle Beams, 2014, 26: 051010 doi: 10.11884/HPLPB201426.051010 [8] 乔杨, 张宁, 徐熙平, 等. 基于共焦法的透镜厚度测量系统设计[J]. 仪器仪表学报, 2011, 32(7): 1635-1641. https://www.cnki.com.cn/Article/CJFDTOTAL-YQXB201107029.htmQiao Yang, Zhang Ning, Xu Xiping, et al. Design of lens thickness measurement system based on confocal technology. Chinese Journal of Scientific Instrument, 2011, 32(7): 1635-1641 https://www.cnki.com.cn/Article/CJFDTOTAL-YQXB201107029.htm [9] 刘乾, 杨维川, 袁道成, 等. 光谱共焦显微镜的线性色散物镜设计[J]. 光学 精密工程, 2013, 21(10): 2473-2479. https://www.cnki.com.cn/Article/CJFDTOTAL-GXJM201310001.htmLiu Qian, Yang Weichuan, Yuan Daocheng, et al. Design of linear dispersive objective for chromatic confocal microscope. Optics and Precision Engineering, 2013, 21(10): 2473-2479 https://www.cnki.com.cn/Article/CJFDTOTAL-GXJM201310001.htm [10] Novak J, Miks A. Hyperchromats with linear dependence of longitudinal chromatic aberration on wavelength[J]. Optik—International Journal for Light and Electron Optics, 2005, 116(4): 165-168.