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摘要:
太赫兹波具有高穿透性、低能性及指纹谱性等特征，被广泛应用于探测领域，因此，设计太赫兹波成像光学系统具有重要的意义和广泛的应用前景。首先，以四块透镜构成的天塞物镜为参考结构，应用近轴光学系统像差理论构建系统像差平衡方程，给出了系统初始结构参数求解函数和方法，再结合光学设计软件进一步校正系统像差，最终设计了一种用于太赫兹波探测的大孔径光学成像系统。该光学系统由4块同轴折射透镜构成，焦距为70 mm，F数为1.4，全视场角为8°，在奈奎斯特频率10 lp/mm处全视场角范围内的调制传递函数（MTF）值均大于0.32，各视场内的弥散斑均方根（RMS）半径均小于艾里斑半径。最后对系统各种公差进行分析和讨论。设计结果表明，本文设计的太赫兹波探测光学成像系统具有孔径大、结构简单且紧凑、成像质量较好且加工性易于实现等特点，满足设计要求，它在太赫兹波段高分辨率探测领域具有重要应用价值。
Abstract:The Terahertz wave has some characteristics of high penetration, low energy and fingerprint spectrum, etc., and is widely used in the detection field. Therefore, design of Terahertz wave detection optical imaging system holds substantial significance and wide application prospects. Firstly, referring to the structure of Tessar objective lens consisting of four lenses, we apply the aberration theory of paraxial optical system to establish the balance equations of aberration of the system, and give solve function and method of the initial structure parameters of the system. Then, by combining with optical design software to further correct the aberration of the system. Finally, a Terahertz wave detection optical imaging system with large aperture is designed. The optical system is composed of four coaxial refractive lenses. Its total focal length is 70 mm, F-number is 1.4, full field of view angle is 8°. The value of modulation transfer function (MTF) in the range of full field of view angle is greater than 0.32 at the Nyquist frequency of 10 lp/mm, and the root mean square (RMS) radius of the diffused spot in each field of view is less than the Airy disk radius. At last, we analyze and discuss the various tolerance types of the system. The design results show that the Terahertz wave detection optical imaging system designed in this paper has a large aperture, a simple and compact form, a light-weight structure, excellent imaging performance and simple processing, etc., which meets the design requirements, and it has important applications in the field of high-resolution detection and other fields within the Terahertz wave band.
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Key words:
- optical system design /
- terahertz wave /
- large aperture /
- aberration balance /
- tolerance analysis
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图 1 光学系统基础结构应用薄透镜简化结构和光路图
Figure 1. Simplify structure and optical pass diagram using thin lens in optical system infrastructure
图 2 光学系统初始结构简化及光路图
Figure 2. Simplified structure and optical path diagram for initial structure of the optical system
图 3 优化设计后的光学系统的光学结构及光路图
Figure 3. Optical structure and optical path diagram of the optical system after optimization design
图 4 优化设计后光学系统的调制传递函数曲线图
Figure 4. MTF curve diagram of the optical system after optimization design
图 5 优化设计后光学系统的点列图
Figure 5. Spot diagram of the optical system after optimization design
图 6 优化设计后光学系统的相对照度曲线图
Figure 6. Relative illumination curve diagram of the optical system after optimization design
图 7 优化设计后光学系统的F-Tan (Theta)畸变曲线图
Figure 7. F-Tan (Theta) distortion curve diagram of the optical system after optimization design
表 1 光学系统设计指标
Table 1. Design specifications of the optical system
Parameter Value Wavelength band/μm 30-35 Effective focal length/mm 70 Full field of view angle/(°) 8 F-number 1.4 Pixel size/μm 52×52 Pixel 240×320 
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表 2 光学系统初始结构的一阶光学参量
Table 2. First-order optical parameter of the initial structure of the optical system (Unit: mm−1, unless otherwise stated)
$ \varPhi_{1} $ $ \varPhi_{2} $ $ \varPhi_{3} $ $ \varPhi_{4} $ $ d_{1} $ $ d_{1} $ $ d_{3} $ −0.0157 0.0356 −0.0201 0.0264 6 mm 15.51 mm 80 mm
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表 3 KRS-5和CsBr材料的Sellmeier函数拟合参数
Table 3. Sellmeier function fitting parameters of KRS-5 and CsBr materials
Sellmeier fitting parameters Material KRS-5 CsBr $ {K}_{1} $ 1.8293958 0.9533786 $ L_{1} $ 2.25×10−2 8.20189243×10−3 $ {K}_{2} $ 1.6675593 0.8303809 $ L_{2} $ 6.25×10−2 2.79396908×10−2 $ {K}_{3} $ 1.1210424 2.847172 $ L_{3} $ 0.1225 1.41646892×104 $ {K}_{4} $ 4.513366×10−2 - $ L_{4} $ 0.2025 - $ {K}_{5} $ 12.380234 - $ L_{3} $ 2.70898681×104 -
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表 4 经优化设计后光学系统的光学结构参数
Table 4. Optical structure parameters of the optical system after optimization design
Surface Type Radius
/mmThickness
/mmMaterial 1 Even Aspheric (STOP) −83.93 6.28 CsBr 2 Even Aspheric 46.66 0.70 3 Even Aspheric 27.45 14.98 KRS-5 4 Even Aspheric 185.48 7.65 5 Even Aspheric −27.00 17.50 CsBr 6 Standard 32.64 3.25 7 Even Aspheric 38.61 17.50 KRS-5 8 Standard 316.43 35.47 Image plane Standard Infinite
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[1] 金钻明, 郭颖钰, 季秉煜, 等. 超快太赫兹自旋光电子学研究进展(特邀)[J]. 光子学报,2022,51(7):0751410. doi: 10.3788/gzxb20225107.0751410JIN Z M, GUO Y Y, JI B Y, et al. Development of ultrafast spin-based terahertz photonics (invited)[J]. Acta Photonica Sinica, 2022, 51(7): 0751410. (in Chinese). doi: 10.3788/gzxb20225107.0751410 [2] 郑江鹏, 余平, 赵萌, 等. 利用低信噪比小样本太赫兹光谱实现心肌淀粉样变检测[J]. 中国光学,2022,15(3):443-453. doi: 10.37188/CO.2021-0223ZHENG J P, YU P, ZHAO M, et al. Detection of myocardial amyloidosis by a small number of terahertz spectra with low signal-to-noise ratio[J]. Chinese Optics, 2022, 15(3): 443-453. (in Chinese). doi: 10.37188/CO.2021-0223 [3] 马卿效, 李春, 李天莹, 等. 基于太赫兹光谱和机器学习算法的二元及三元混合物定量分析[J]. 与光电子学进展,2022,59(19):1930003.MA Q X, LI CH, LI T Y, et al. Quantitative analysis of binary and ternary mixtures based on Terahertz spectroscopy and machine learning algorithm[J]. Laser & Optoelectronics Progress, 2022, 59(19): 1930003. (in Chinese). [4] 卢雪晶, 葛宏义, 蒋玉英, 等. 太赫兹技术在农产品检测中的应用研究进展[J]. 光谱学与光谱分析,2022,42(11):3330-3335.LU X J, GE H Y, JIANG Y Y, et al. Application progress of Terahertz technology in agriculture detection[J]. Spectroscopy and Spectral Analysis, 2022, 42(11): 3330-3335. (in Chinese). [5] 胡军, 刘燕德, 孙旭东, 等. 基于BP神经网络的太赫兹时域光谱对面粉中苯甲酸的定量检测研究[J]. 与光电子学进展,2020,57(7):302-308.HU J, LIU Y D, SUN X D, et al. Quantitative determination of benzoic acid in flour based on Terahertz time-domain spectroscopy and BPNN model[J]. Laser & Optoelectronics Progress, 2020, 57(7): 302-308. (in Chinese). [6] 王华泽, 吴晗平, 吕照顺, 等. 太赫兹成像系统分析及其相关技术研究[J]. 红外技术,2013,35(7):391-397.WANG H Z, WU H P, LV ZH SH, et al. Research on THz imaging system and related technologies[J]. Infrared Technology, 2013, 35(7): 391-397. (in Chinese). [7] 曹恩达, 于勇, 宋长波, 等. 一种手持式太赫兹探测系统的光学及结构设计[J]. 遥测遥控,2020,41(2):1-9.CAO E D, YU Y, SONG CH B, et al. An optical and structural design of a hand-held Terahertz detection system based on ZEMAX and ProE[J]. Journal of Telemetry, Tracking and Command, 2020, 41(2): 1-9. (in Chinese). [8] 耿贺彬, 李超. 一种太赫兹透镜优化方法[J]. 电子测量技术,2020,43(8):159-165,188. (in Chinese). doi: 10.19651/j.cnki.emt.1903888GENG H B, LI CH. Optimization approach for Terahertz lens[J]. Electronic Measurement Technology, 2020, 43(8): 159-165, 188. doi: 10.19651/j.cnki.emt.1903888 [9] 杨旭, 牟达, 陈炳旭, 等. 基于太赫兹波段的三反变焦系统设计[J]. 长春理工大学学报(自然科学版),2021,44(1):1-6.YANG X, MU D, CHEN B X, et al. Design of three reflective zoom system based on Terahertz band[J]. Journal of Changchun University of Science and Technology (Natural Science Edition), 2021, 44(1): 1-6. (in Chinese). [10] 李志雷, 刘海峰, 池威威, 等. 基于太赫兹光谱技术的光学系统设计及应用[J]. 应用光学,2022,43(3):409-414. doi: 10.5768/JAO202243.0301005LI ZH L, LIU H F, CHI W W, et al. Design and application of optical system based on Terahertz spectroscopy technology[J]. Journal of Applied Optics, 2022, 43(3): 409-414. (in Chinese). doi: 10.5768/JAO202243.0301005 [11] 宋菲君, 陈笑, 刘畅. 近代光学系统设计概论[M]. 北京: 科学出版社, 2019.SONG F J, CHEN X, LIU CH. An Introduction to the Modern Optical System Design[M]. Beijing: Science Press, 2019. (in Chinese). [12] 李梅. 15~38 μm太赫兹波成像光学系统设计研究 [D]. 长春: 长春理工大学, 2006.LI M. Design study of 15-38 μm THz spectrum wave band imaging optical system[D]. Changchun: Changchun University of Science and Technology, 2006. (in Chinese). [13] BORN M, WOLF E. Principles of Optics[M]. Cambridge: Cambridge University, 2005. [14] 史光辉. 用高斯光学和三级像差理论求变焦距物镜的初始解[J]. 中国光学,2018,11(6):1047-1060. doi: 10.3788/co.20181106.1047SHI G H. Find preliminary solution of zoom objective lens using Gaussian optics and third-order aberration theory[J]. Chinese Optics, 2018, 11(6): 1047-1060. (in Chinese). doi: 10.3788/co.20181106.1047 [15] 沈志娟, 曹一青. 大相对孔径长焦距同轴折反射式望远物镜设计[J]. 与光电子学进展,2021,58(1):0108002.SHEN ZH J, CAO Y Q. Design of a coaxial catadioptric telescope objective with a large relative aperture and long focal length[J]. Laser & Optoelectronics Progress, 2021, 58(1): 0108002. (in Chinese). [16] 曹桂丽, 刘芳芳, 贾永丹, 等. 大相对孔径、长焦距的紫外告警光学系统设计[J]. 与光电子学进展,2019,56(12):122203.CAO G L, LIU F F, JIA Y D, et al. Design of ultraviolet warning optical system with large relative aperture and long focal length[J]. Laser & Optoelectronics Progress, 2019, 56(12): 122203. (in Chinese). [17] 李康, 周峰, 王保华, 等. 制冷型被动式消热差红外光学系统设计[J]. 中国光学(中英文),2023,16(4):853-860. doi: 10.37188/CO.2022-0205LI K, ZHOU F, WANG B H, et al. Passive athermalization design of a cooled infrared optical system[J]. Chinese Optics, 2023, 16(4): 853-860. (in Chinese). doi: 10.37188/CO.2022-0205 -
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