Fabrication and test of high-precision off-axis aspheric lens

Zhong Bo; Chen Xianhua; Wang Jian; Zhou Lian; Shi Qikai; Deng Wenhui

doi:10.3788/IRLA201847.0718003

In order to meet the requirement of high precision and mass manufacturing of large aspheric lens for high power laser device, a novel manufacturing method combining the bonnet polishing(BP) technology and flexible pitch polishing(FPP) technology was explored. Firstly, after the aspheric generating by ultra-precision grinding, the bonnet polishing technology, in keeping the aspherical surface shape, was used to quickly remove the grinding defect layer and improve the roughness of the element so that it can be directly tested by interferometer. Then, the bonnet polishing technology was used to quickly correct the low frequency error. Finally, the flexible pitch tool was adopted to smooth the middle and high frequency error. During the polishing process, the self-built wavefront detection system and the roughness instrument were used to detect the full frequency error of the aspheric element. Based on the above-mentioned fabrication and testing method, a 430 mm430 mm off-axis apherical lens was manufactured, and the results indicate that, after polishing, the PV, GRMS, PSD1 RMS, PSD2 RMS and Rq are 0.1, 5.7 nm/cm, 1.76 nm, 1 nm and 0.6 nm, respectively. In addition, the power spectral density(PSD) curves are below the required evaluation curve. The experimental results show that the full frequency specifications of the off-axis aspheric lens meet the requirements. The manufacturing method is also applicable to the high-precision manufacturing of other types of large aspheric optical elements.

Fabrication and test of high-precision off-axis aspheric lens

1. Research Center of Laser Fusion,China Academy of Engineering Physics,Mianyang 621900,China;

2. School of Mechanical and Electrical Engineering,University of Electronic Science and Technology of China,Chengdu 610054,China

Received Date: 2018-02-05

Rev Recd Date: 2018-03-03

Publish Date: 2018-07-25

Key words:

Abstract: In order to meet the requirement of high precision and mass manufacturing of large aspheric lens for high power laser device, a novel manufacturing method combining the bonnet polishing(BP) technology and flexible pitch polishing(FPP) technology was explored. Firstly, after the aspheric generating by ultra-precision grinding, the bonnet polishing technology, in keeping the aspherical surface shape, was used to quickly remove the grinding defect layer and improve the roughness of the element so that it can be directly tested by interferometer. Then, the bonnet polishing technology was used to quickly correct the low frequency error. Finally, the flexible pitch tool was adopted to smooth the middle and high frequency error. During the polishing process, the self-built wavefront detection system and the roughness instrument were used to detect the full frequency error of the aspheric element. Based on the above-mentioned fabrication and testing method, a 430 mm430 mm off-axis apherical lens was manufactured, and the results indicate that, after polishing, the PV, GRMS, PSD1 RMS, PSD2 RMS and Rq are 0.1, 5.7 nm/cm, 1.76 nm, 1 nm and 0.6 nm, respectively. In addition, the power spectral density(PSD) curves are below the required evaluation curve. The experimental results show that the full frequency specifications of the off-axis aspheric lens meet the requirements. The manufacturing method is also applicable to the high-precision manufacturing of other types of large aspheric optical elements.

HTML

Reference (15)

[1]	Semenov A P, Abdulkadyrov M A, Belousov S P, et al. Technological features of the fabrication of the primary mirrors of telescopes[J]. J Opt Technol, 2013, 80(4):207-213.
[2]	Spaeth M L, Manes K R, Widmayer C C, et al. The national ignition facility wavefront requirements and optical architecture[J]. Optical Engineering, 2004, 43(12):25-42.
[3]	Martin H M, Allen R G, Burge J H, et al. Fabrication and testing of the first 8.4 m off-axis segment for the Giant Magellan Telescope[C]//SPIE, 2010, 7739:77390A.
[4]	Yu G Y, Walker D D, Li H Y. Research on fabrication of mirror segments for E-ELT[C]//SPIE, 2012, 8416:841602.
[5]	Glatzel H, Ashworth D, Bremer M, et al. Projection optics for extreme ultraviolet lithography(EUVL) micro-field exposure tools (METs) with a numerical aperture of 0.5[C]//SPIE Advanced Lithography, 2013, 8679(1):867917.
[6]	Meng Xiaohui, Wang Yonggang, Ma Xianmei, et al. Fabrication and test for Ф520 mm secondary mirror of on-axis three mirror space camera[J]. Infrared and Laser Engineering, 2017, 46(8):0818002. (in Chinese)
[7]	Zhang Xin, Luo Xiao, Yan Lisong, et al. Technology of large aperture off-axis parabolic mirror with Tri-station processing center[J]. Infrared and Laser Engineering, 2016, 45(8):0819001. (in Chinese)
[8]	Aikens D M. The origin and evolution of the optics for the national ignition facility[C]//SPIE, 1995, 2536:2-12.
[9]	Campbell J H, Hawley-Fedder R, Stolz C J. NIF optical materials and fabrication technologies:an overview[C]//SPIE, 2004:5341.
[10]	Pan J H. Design, Fabrication and Test of Optical Aspheric Surface[M]. Suzhou:Soochow University Press, 2004. (in Chinese)
[11]	Chen H B, Wang Y W, Feng Z J. Methods to determine best fit sphere for large off-axis aspheric lens[J]. Journal of Tsinghua University (Science and Technology), 2004, 44(8):1040-1042. (in Chinese)
[12]	Dumas P, Hall C, Hallock B, et al. Complete sub-aperture pre-polishing finishing solution to improve speed and determinism in asphere manufacture[C]//SPIE, 2007, 6671:1-11.
[13]	Hu H, Song C, Xie X. Combined fabrication technique for high-precision aspheric optical windows[C]//SPIE, 2016, 9912:99123W.
[14]	Zhong B, Chen X H, Pan R, et al. The effect of tool wear on the removal characteristics in high-efficiency bonnet polishing[J]. The International Journal of Advanced Manufacturing Technology, 2017, 91:3653-3662.
[15]	Chen X H, Zhong B, Wang J, et al. Distortion of removal function based on the local asphericity of aspheric surface and the viscoelasticity of polishing tool in computer-controlled optical surfacing[J]. J Mechanical Engineering Science, 2018, 232(7):1135-1145.

Fabrication and test of high-precision off-axis aspheric lens

doi: 10.3788/IRLA201847.0718003

Abstract

References

Proportional views

通讯作者: 陈斌, bchen63@163.com

Article Metrics

Related

Proportional views