COIS Group

We are Computational Optics Imaging and Sensing (COIS) Group in Prof. Fan Wang's Lab in Beihang University, Beijing, China. Our research interests are in designing algorithms based optical imaging, microscopy, and sensing systems, including Fluorescent Super-resolution Imaging, Single-pixel/Ghost imaging, Diffuser based Camera, Computational Spectrometer/Hyperspectral Imaging, Fiber Imaging, Wavefront Shaping, Scattering Imaging and Novel Imaging Methods. Innovation in these areas would finds applications in bio-medical, industrial and physical research, which often operates right at the limit of current technology.


  • 2/2024, the dark-field UV ghost imaging paper has been accepted by Photonics Research, Congratulations to Jiaqi.
  • 5/2023, the interference lithography paper has been accepted by Optics Express, Congratulations to Jiaqi.
  • 4/2023, the A-SVD ghost imaging paper has been accepted by Optics Express, Congratulations to Dajing.
  • 8/2022, one paper has been accepted by Nano Letters.
  • 8/2022, one paper has been accepted by Advanced Science.
  • 11/2021, one paper has been published as the front cover paper of Nanoscale Advances.
  • 10/2021, one paper has been accepted by IEEE Photonics Journal.
  • 10/2021, one paper has been accepted by Optica.
  • 07/2021, the laser-speckle image captured by me is selected as the Image of the Week by Optics & Photonics News of Optica. [Link 1 Link 2]

  • 03/2020, one paper has been published as the front cover paper of Nano Letters.
  • Recent Projects

  • Computational Imaging Using Spatially Modulated Optical Fields
  • Computational Microscopy
  • Papers: ArXiv preprint (2024) | Nano Letters (2022) | Nano Letters (2020) | Nanoscale Advances | Advanced Materials

    We are developing nover microscopy methods to overcome the current limitations of traditional solutions, with a multidisciplinary approach. Several keywords are super-resolution Imaging, deep-tissue imaging, structured illumination, near-infrared, wavefront shaping, adaptive optics, unconversion nanoprobes and so on.

  • Single-pixel Imaging
  • Papers: Optica | Photonics Research | Optics Express | IEEE Photonics Journal | Journal of Modern Optics | Acta Opt Sinica

    The single-pixel imaging technique produces images without the need for a 2D detector, making use of structured detection or illumination of the object to computationally derive an image. We are developing the novel single-pixel imaging methods for imaging through scattering medium, hyperspectral imaging,edge imaging, dark-field imaging, lifetime imaging and so on.

  • Lensless Imaging
  • Papers: ArXiv preprint (2023)

    In this direction, we try to delelop ultra-compacted lensless imaging systems for high-dimensional imaging to recover the depth, spectral, polarization, temporal and phase (XYZλθτφ) information of targets. A example of such devices is our Diffuser-based camera.

  • Computational Spectrometer
  • Papers: ArXiv preprint (2024) |

    As one of the recently rised research topic, computational spectrometer offers high spectral measurement performance but with much smaller size or footprint than a traditional spectrometer. We are developing computational spectrometer with easy-to-prepare and low-cost implementation.

  • Fiber Endoscopy
  • Papers: Optica

    We are developing the single-multimode fiber or fiber-bundle based endoscopes for high-resolution and hyper-spectral imaging.


    We are an interdisciplinary group, made up of people from many different backgrounds.


    Baolei Liu
    liubaolei [at] buaa [dot] edu [dot] cn
    Lecture / Postdoctoral Research Fellow, School of Physics
    Affiliate, Nanophotonics group
    BS, Optoelectronic Information Engineering, UPC, 2014
    MEng, Instrument science and technology, Beihang, 2017
    PhD, Electronic engineering, UTS, 2022
    Email  /  Google Scholar  /  Researchgate  /  ORCID  /  Twitter

    Graduate students

    Yao Wang (Co-supervised)
    PhD Student, Beihang University, since 2023
    MS, EE, Harbin Institute of Technology, 2022
    BS, EE, Harbin Institute of Technology, 2020
    Jiaqi Song (Co-supervised)
    XX [at] XX [dot] XX
    PhD Student, Beihang University, since 2019
    BS, Applied Physics, Capital Normal University, 2019
    Ze Zheng (Co-supervised)
    XX [at] XX [dot] eduXX
    PhD, XX, XX University, 20XX
    MS, ECE, XX University, 20XX
    BS, XX, XX University, 20XX
    Menghan Tian (Co-supervised)
    XX [at]XX [dot] edu
    PhD Student, Beihang University, since 2019
    MS, Optics, Beihang University, 2019
    BE, Applied Physics, Yantai University, 2018


    We are interested in devleoping new methods for Super-resolution Imaging | Optics in complex media | Nanophotonics | Single-pixel Imaging | Optical Fiber Sensing | Novel Imaging Methods, etc. Our research articles are published in journals related to nanophotonics and optical imaging, such as Optica, Nano Letters, Advanced Materials, Advanced Science, Optics Express, etc.

    Journal Papers:


    1. Multi-photon super-linear image scanning microscopy using upconversion nanoparticles
      Y. Wang, B. Liu ✉, L. Ding, C. Chen, X. Shan, D. Wang, M. Tian, J. Song, Z. Zheng, X. Xu, X. Zhong, and F. Wang,
      ARXIV preprint, arXiv, 2023. [IF: XX, LINK].

    2. Miniaturized spectrometer based on tunable electrochromic device
      M. Tian, B. Liu ✉, J. Song, X. Zhong, and Fan Wang,
      ARXIV preprint, arXiv, 2023. [IF: XX, LINK].

    3. Temporal compressive edge imaging enabled by a lensless diffuser camera
      Z. Zheng, B. Liu ✉, J. Song, L. Ding, X. Zhong, D. Mcgloin, and Fan Wang ✉,
      ARXIV preprint, arXiv:2309.07198, 2023. [IF: XX, LINK].

    4. Computational and dark-field ghost imaging with ultraviolet light
      J. Song, B. Liu ✉, Y. Wang, C. Chen, X. Shan, X. Zhong, L.-A. Wu, and Fan Wang,
      Photonics Research, 12(2), 226-234, 2024. [IF: 7.6, LINK, PDF].

    5. Optical Nonlinearity Enabled Super-Resolved Multiplexing Microscopy
      L. Ding, C. Chen, X. Shan, B. Liu, D. Wang, Z. Du, G. Zhao, Q. P. Su, Y. Yang, B. Halkon, T. T. Tran, J. Liao, I. Aharonovich, M. Zhang, F. Cheng, L. Fu, X. Xu, and Fan Wang
      Advanced Materials, 2308844, 2023. [IF: 29.4, LINK].

    6. Multi-functional dual-path self-aligned polarization interference lithography
      J. Song, B. Liu, X. Shan, F. Wang, and X. Zhong,
      Optics Express, 31(11), 17629-17644, 2023. [IF: 3.833, LINK].

    7. Dual-mode adaptive-SVD ghost imaging
      D. Wang, B. Liu ✉, J. Song, Y. Wang, X. Shan, X. Zhong, and F. Wang ✉,
      Optics Express, 31(9), 14225-14239, 2023. [IF: 3.833, LINK].

    8. Trapped aerosol sizes under fiber-based counter-propagation optical trapping
      L. Zhang, A. Szmalenberg, K. Cook, B. Liu, L. Ding, F. Wang, and D. McGloin,
      Journal of the Optical Society of America B, 40(2), 460-468, 2023. [IF: 2.058, LINK]

    9. Lanthanide Ion Resonance-Driven Rayleigh Scattering of Nanoparticles for Dual‐Modality Interferometric Scattering Microscopy
      L. Ding, X. Shan, D. Wang, B. Liu ✉, Z. Du, X. Di, C. Chen, M. Maddahfar, L. Zhang, Y. Shi, P. Reece, B. Halkon, I. Aharonovich, X. Xu, F. Wang ✉,
      Advanced Science, 9(32), 2203354, 2022. [IF: 17.521, published as the inside back cover, LINK]   

    10. Exploiting Dynamic Nonlinearity in Upconversion Nanoparticles for Super-Resolution Imaging
      C. Chen, L. Ding, B. Liu ✉, Z. Du, Y. Liu, X. Di, X. Shan, C. Lin, M. Zhang, X. Xu, X. Zhong, J. Wang, L. Chang, B. Halkon, X. Chen, F. Cheng, F. Wang ✉,
      Nano Letters, 22(17), 7136–7143, 2022. [IF: 12.263, LINK]

    11. Multiplexed structured illumination super-resolution imaging with lifetime-engineered upconversion nanoparticles
      B. Liu, J. Liao, Y. Song, C. Chen, L. Ding, J. Zhou, and F. Wang,
      Nanoscale Advances, 4(1), 30-38, 2022. [IF: 5.598, published as the front cover, PDF]


    12. Single-pixel diffuser camera
      B. Liu, F. Wang, C. Chen, and D. McGloin,
      IEEE Photonics Journal, 13(6), 7800205, 2021. [IF: 2.443, PDF]

    13. Self-evolving ghost imaging
      B. Liu, F. Wang, C. Chen, F. Dong, and D. McGloin,
      Optica, 8(10), 1340-1349, 2021. [IF: 11.104, PDF]

    14. Optical Fingerprint Classification of Single Upconversion Nanoparticles by Deep Learning
      J. Liao, J. Zhou, Y. Song, B. Liu, J. Lu, and D. Jin,
      Journal of Physical Chemistry Letters, 12(41), 10242–10248, 2021. [IF: 6.475, PDF]


    15. Preselectable Optical Fingerprints of Heterogeneous Upconversion Nanoparticles
      J. Liao, J. Zhou, Y. Song, B. Liu, Y. Chen, F. Wang, C. Chen, J. Lin, X. Chen, J. Lu, and D. Jin,
      Nano Letters, 21(18), 7659–7668, 2021. [IF: 11.189, Q1 Top, PDF]


    16. Heterochromatic nonlinear optical responses in upconversion nanoparticles for super-resolution nanoscopy
      C. Chen, B. Liu, Y. Liu, J. Liao, X. Shan, F. Wang and D. Jin,
      Advanced Materials, 33(23), 2008847, 2021. [IF: 30.849, PDF]


    17. Upconversion Nonlinear Structured Illumination Microscopy
      B. Liu, C. Chen, X. Di, J. Liao, S. Wen, Q.P. Su, X. Shan, Z.Q. Xu, L.A. Ju, C. Mi, F. Wang, and D. Jin,
      Nano Letters, 20(7), 4775-4781, 2020. [IF: 11.189, published as the front cover, PDF]


    18. Video-rate upconverting display by optimizing lanthanide ions doped upconversion nanoparticles
      L. Gao, X. Shan, X. Xu, Y. Liu, B. Liu, S. Li, S. Wen, C. Ma, D. Jin, and F. Wang,
      Nanoscale, 12(36), 18595–18599, 2020. [IF: 6.895, PDF]


    19. Quantitative lateral flow strip sensor using highly doped upconversion nanoparticles
      H. He, B. Liu, S. Wen, J. Liao, G. Lin, J. Zhou, and D. Jin,
      Analytical Chemistry, 90(21), 12356-12360, 2018. [IF: 6.785, Q1 Top, citation: 80, PDF]

    20. Coloured computational imaging with single-pixel detectors based on a 2D discrete cosine transform
      B. Liu, Z. Yang, X. Liu, and L. Wu,
      Journal of Modern Optics, 64(3), 259-264, 2017. [IF: 1.657, citation: 80, rank 3rd place in most cited papers in 2017 of the journal, PDF]

    21. Normalized iterative denoising ghost imaging based on the adaptive threshold
      G. Li, Z. Yang, Y. Zhao, R. Yan, X. Liu, and B. Liu,
      Laser Physics Letters, 14(2), 025207, 2017. [IF: 2.328, PDF]

    22. Influence of turbid media at different locations in computational ghost imaging
      B. Liu, Z. Yang, S. Qu, A. Zhang, and L. Wu,
      Acta Opt Sinica, 36 (10), 1026017, 2016. PDF]

    Conference Papers:

    1. Self-optimizing ghost imaging with a genetic algorithm
      B. Liu, X. Shan, J. Zhu, C. Chen, Y. Liu, F. Wang, and D. McGloin,
      14th Pacific Rim Conference on Lasers and Electro-Optics (CLEO PR 2020), Optical Society of America, paper C1G_3, 2020. [PDF]

    2. 0.32 THz dual circularly polarized reflect array
      J. Zhu, D. McGloin, Y. Yang, and B. Liu,
      14th Pacific Rim Conference on Lasers and Electro-Optics (CLEO PR 2020), Optical Society of America, paper C11B_3, 2020. [PDF]

    3. A novel correlation imaging method using a periodic light source array
      B. Liu, Z. Yang, A. Zhang, and L. Wu,
      Proceedings of SPIE, 10154, 1015413, 2016. [PDF]

    4. Dual beam optical fiber traps for aerosols with angular deviation
      L. Zhang, K. Cook, A. Szmalenberg, B. Liu, L. Ding, F. Wang, D. McGloin,
      Proceedings of SPIE, 12017, Complex Light and Optical Forces XVI, 120170G, 2022. [Link]

    5. Lanthanide ions in nanocrystals for biophotonics application
      18. C. Chen, B. Liu, J. Liao, L. Ding, X. Shan, F. Wang,
      Proceedings of SPIE, 12277, 2021 International Conference on Optical Instruments and Technology: Optical Systems, Optoelectronic Instruments, Novel Display, and Imaging Technology, 2022. [Link]

    Patent of invention:

    1. Single-optical arm correlation imaging method for compensating atmospheric turbulence
      Z. Yang, B. Liu, et al,
      CN: 106154284B, 2017. [PDF]

    2. Single-pixel rapid active imaging system based on discrete cosine transform
      Z. Yang, B. Liu,
      CN: 104992424B, 2018. [PDF]

    3. Single-pixel imaging system and method based on array light source
      Z. Yang, B. Liu, et al,
      CN: 106019307A, 2016. [PDF]

    4. A polarization-interference-type fully distributed double-parameter optical fiber sensor
      N. Wang, J. Fu, X. Li, B. Liu, et al,
      CN: 203561381U, 2014. [PDF]

    5. A reservation type heat insulated cup
      B. Liu,
      CN 203137917U, 2013. [PDF]

    Conference Presentations

    1. 08/2020, B. Liu, et al. “Self-optimizing ghost imaging with a genetic algorithm”, Conference on Lasers and Electro-Optics/Pacific Rim (CLEO PR), Optical Society of America (OSA), Sydney, Australia. (Oral presentation)
    2. 02/2020, Chen Chaohao, B. Liu, et al. “Multiplexed intermediate states saturation nanoscopy by Fourier spectral fusion”, The 8th International Conference on Nanoscience and Nanotechnology (ICONN 2020), Brisbane, Australia. (Oral presentation)
    3. 02/2020, B. Liu, et al. “Near-infrared nonlinear structured illumination microscopy for in-depth super-resolution imaging”, The 8th International Conference on Nanoscience and Nanotechnology (ICONN 2020), Brisbane, Australia. (Poster presentation)
    4. 01/2020, B. Liu, et al. “Upconversion assisted dual-NIR structured illumination microscopy”, The international Conference on Nanomaterial and Atomaterial Science and Applications (ICNASA 2020), Melbourne, Australia. (Oral presentation)
    5. 08/2020, B. Liu, et al. “A novel correlation imaging method using a periodic light source array”. Advanced Optical Design and Manufacturing Technology and Astronomical Telescopes and Instrumentation, International Society for Optics and Photonics (SPIE). (Poster presentation)
    6. 08/2016, B. Liu, et al. “A double threshold multi-wavelength collated imaging”, Chinese Physical Society Autumn Meeting, Beijing, China. (Poster presentation)
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