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XIN Tao, PENG Shuo, DONG Li-quan, ZHANG Shao-hui, ZHANG Cun-lin. Improving terahertz imaging by light field processing[J]. Chinese Optics. doi: 10.37188/CO.EN.2022-0005
Citation: XIN Tao, PENG Shuo, DONG Li-quan, ZHANG Shao-hui, ZHANG Cun-lin. Improving terahertz imaging by light field processing[J]. Chinese Optics. doi: 10.37188/CO.EN.2022-0005

Improving terahertz imaging by light field processing

doi: 10.37188/CO.EN.2022-0005
Funds:  Supported by Founding of National Key Research and Development Program of China (No. 2021YFC2202400); Foundation Enhancement Program (No. 2021-JCJQ-JJ-0823); National Natural Science Foundation of China (No. 61735003)
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  • Author Bio:

    XIN Tao (1971—), male, was born in Shi jia Zhuang, Hebei province. He received his bachelor's degree from Hebei University of Mechanical and Electrical Engineering in 1995 and his master's degree from Yanshan University in 2004. He now works at the Vocational and Technical College of Hebei Normal University. His research interests include terahertz imaging and computer graphics problems, particularly the optimization of terahertz images using light field techniques. E-mail: xintao71@mail.hebtu.edu.cn

    PENG Shuo (1995—), female, was born in ShijiaZhuang. Hebei province. She received the B.Eng degree from Beijing Institute of Technology in 2017 and is currently working toward the D.Eng degree at School of Optics and Photonics, BIT. Her research interests include light-field imaging and 3D measurement. E-mail: pengshuoeve@163.com

  • Corresponding author: zhangshaohui@bit.edu.cncunlin_zhang@cnu.edu.cn
  • Received Date: 31 Mar 2022
  • Accepted Date: 13 May 2022
  • Rev Recd Date: 21 Apr 2022
  • Available Online: 10 Jun 2022
  • Terahertz (THz) technology becomes increasingly important nowadays, especially in testing and security applications. Extending the field of view and increasing the imaging quality are both vital challenges for THz imaging. To address these problems, we build a THz light field imaging system based on a single-camera scanning configuration, which utilizes the 4D information of the spatial and angular distribution of THz waves. Based on the 4D plenoptic function and the parameterization method with two parallel planes, the intensity consistency of THz propagation is used for refocusing calculation, then a series of refocused images can be obtained by integrating original light field images corresponding to different imaging distances and views. Compared with the original THz imaging, the field of view and the imaging quality of the THz light field imaging are effectively improved. In our experiment, the field of view was enlarged by a factor of 1.84 and the resolution increased from 1.3 mm to 0.7 mm. Furthermore, information on some obscured targets could also be retrieved by defocusing the obstructions. This method could improve the imaging quality of THz imaging as well as expand its functions, which inspires a new way THz nondestructive testing (NDT) and security inspection.


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  • [1]
    ZHANG Y D, DENG C, SUN W F, et al. Terahertz continuous-wave transmission imaging system and its application in security inspections[J]. Proceedings of SPIE, 2008, 6840: 684010.
    MITTLEMAN D M. Twenty years of terahertz imaging [Invited][J]. Optics Express, 2018, 26(8): 9417-9431. doi: 10.1364/OE.26.009417
    YAO J Q, LU Y, ZHANG B G, et al. New research progress of THz radiation[J]. Journal of Optoelectronics·Laser, 2005, 16(4): 503-510.
    LEE A W, HU Q. Real-time, continuous-wave terahertz imaging by use of a microbolometer focal-plane array[J]. Optics Letters, 2005, 30(19): 2563-2565. doi: 10.1364/OL.30.002563
    KARPOWICZ N, ZHONG H, ZHANG C L, et al. Compact continuous-wave subterahertz system for inspection applications[J]. Applied Physics Letters, 2005, 86(5): 054105. doi: 10.1063/1.1856701
    VALUŠIS G, LISAUSKAS A, YUAN H, et al. Roadmap of terahertz imaging 2021[J]. Sensors, 2021, 21(12): 4092. doi: 10.3390/s21124092
    YANG J, RUAN SH CH, ZHANG M, et al. Real-time continuous-wave imaging with a 1.63THz OPTL and a pyroelectric camera[J]. Optoelectronics Letters, 2008, 4(4): 295-298. doi: 10.1007/s11801-008-8036-0
    XIAO H, ZHU F. Identification of dangerous goods in human THZ images[C]. Proceedings of the 2018 International Conference on Network, Communication, Computer Engineering (NCCE 2018), Atlantis Press, 2018: 899-903.
    WOODWARD R M, WALLACE V P, ARNONE D D, et al. Terahertz pulsed imaging of skin cancer in the time and frequency domain[J]. Journal of Biological Physics, 2003, 29(2-3): 257-259.
    TAO Y H, FITZGERALD A J, WALLACE V P. Non-contact, non-destructive testing in various industrial sectors with terahertz technology[J]. Sensors, 2020, 20(3): 712. doi: 10.3390/s20030712
    WONG T M, KAHL M, BOLIVAR P H, et al. . Frequency Modulated Continuous Wave (FMCW) THz Image 3D Superresolution[Z]. arXiv: 1802.05457v1, 2018.
    LEVOY M. Light fields and computational imaging[J]. Computer, 2006, 39(8): 46-55. doi: 10.1109/MC.2006.270
    WU G CH, MASIA B, JARABO A, et al. Light field image processing: an overview[J]. IEEE Journal of Selected Topics in Signal Processing, 2017, 11(7): 926-954. doi: 10.1109/JSTSP.2017.2747126
    FANG L, DAI Q H. Computational light field imaging[J]. Acta Optica Sinica, 2020, 40(1): 0111001. doi: 10.3788/AOS202040.0111001
    YIN Y K, YU K, YU CH ZH, et al. 3D imaging using geometric light field: a review[J]. Chinese Journal of Lasers, 2021, 48(12): 1209001. (in Chinese)
    LI Y, WANG X, ZHOU G, et al. Overview of 4D Light Field Representation[J]. Laser &Optoelectronics Progress, 2021, 58(18): 1811012. (in Chinese)
    TIAN Y, ZENG H Q, HOU J H, et al. Light field image quality assessment via the light field coherence[J]. IEEE Transactions on Image Processing, 2020, 29: 7945-7956. doi: 10.1109/TIP.2020.3008856
    COUILLAUD J, ZIOU D. Light field variational estimation using a light field formation model[J]. The Visual Computer, 2020, 36(2): 237-251. doi: 10.1007/s00371-018-1599-2
    YAO T, SANG X ZH, WANG P, et al. Depth reconstruction for 3D light-field display based on axially distributed light field[J]. Optical Engineering, 2021, 60(5): 053103.
    ZHOU G, LI S, LAM E Y. Light field image restoration in low-light environment[J]. Proceedings of SPIE, 2020, 11525: 115251H.
    GUO C L, JIN J, HOU J H, et al. . Accurate light field depth estimation via an occlusion-aware network[C]. IEEE International Conference on Multimedia and Expo (ICME), IEEE, 2020.
    JAIN R, GRZYB J, PFEIFFER U R. Terahertz light-field imaging[J]. IEEE Transactions on Terahertz Science and Technology, 2016, 6(5): 649-657.
    LYU N F, ZUO J, ZHAO Y M, et al. Terahertz synthetic aperture imaging with a light field imaging system[J]. Electronics, 2020, 9(5): 830. doi: 10.3390/electronics9050830
    LYU N F, ZUO J, ZHAO Y M, et al. Layer-resolving terahertz light-field imaging based on angular intensity filtering method[J]. Sensors, 2021, 21(22): 7451. doi: 10.3390/s21227451
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