Hi there — I'm Zekun 👋 PhD candidate in Optical Engineering at Sichuan University (SCU), China, working in Prof. Dahai Li’s research group. Visiting Student at Nanyang Technological University (NTU), Singapore, working with Prof. Kemao Qian's research group. My research focuses on phase-measuring deflectometry (PMD) for high-accuracy, high-precision measurement of optical wavefronts and specular surfaces. My work spans two complementary directions: extending deflectometry from wavefront metrology to quantitative 3D flow-field reconstruction, and advancing non-contact optical measurement toward interferometer-level accuracy. If light bends, there is probably a field waiting to be reconstructed.

Shot in 2022 at SCU A121Lab Optics · Imaging · Computation

Nanometre-scale surface-form measurement using phase-measuring deflectometry. The setup combines multi-view calibration with quantitative surface reconstruction, while the results are benchmarked against interferometric measurements across progressively extended Zernike-term ranges.

_{Nanometre-scale surface metrology · experimental setup (left) and interferometry–deflectometry comparison from 1–3 to 1–11 terms (right)}

High-precision transmitted-wavefront measurement based on phase-measuring deflectometry. Measurements of high-quality flat optics show nanometre-scale agreement with interferometric results.

Experimental setup · coded fringes, camera, screen, and 100 mm test optic

Nanometre-scale validation · deflectometry results benchmarked against interferometric measurements

Quantitative visualization of refractive-index and density fields from phase-measuring deflectometry, connecting reference fringes, disturbed measurements, and reconstructed deflection fields.

Hot-air plume · reference fringes, disturbed fringes, and the resultant deflection field

Flame flow · reference fringes, disturbed fringes, and the resultant deflection field

Multi-view phase-measuring deflectometry for quantitative three-dimensional temperature-field reconstruction, combining geometry self-consistent calibration, deflection-angle recovery, and volumetric inversion.

_{Multi-view volumetric temperature-field reconstruction · eight-camera acquisition, deflection-angle measurement, geometric calibration, and reconstructed isothermal surfaces}

Synced from my public ORCID record on 13 August 2026 · 12 works

1. Volumetric flow field measurement deflectometry via a geometry self-consistent framework — Optics Letters (2026).
   _{Zekun Zhang; Xinwei Zhang; Ruiyang Wang; Renhao Ge; Manwei Chen; Zonglin Jiang; Dahai Li}

2. High-accuracy and full-frequency surface measurement method for specular element based on stereo deflectometry — Measurement (2026).
   _{Renhao Ge; Ruiyang Wang; Dahai Li; Xinwei Zhang; Zekun Zhang; Manwei Chen}

3. Noncontact Quantitative Temperature Field Reconstruction of Axisymmetric Flames With Phase Measurement Deflectometry — IEEE Transactions on Instrumentation and Measurement (2025).
   _{Zekun Zhang; Yuting Liu; Ruiyang Wang; Wei Hu; Renhao Ge; Manwei Chen; Jun Wu; Dahai Li}

4. In situ online deflectometry with synchronized calibration and measurement — Optics Letters (2025).
   _{Ruiyang Wang; Renhao Ge; Daewook Kim; Zekun Zhang; Manwei Chen; Dahai Li; Shouhuan Zhou}

5. Sub-Nyquist sampling rate temporal correlation method for measuring the surface of the transparent planar element — Optics Express (2025).
   _{Wanxing Zheng; Dahai Li; Ruiyang Wang; Manwei Chen; Zekun Zhang; Renhao Ge}

6. In-situ high-accuracy figure measurement based on stereo deflectometry for off-axis aspheric mirror — Optics Express (2025).
   _{Renhao Ge; Ruiyang Wang; Dahai Li; Zekun Zhang; Manwei Chen}

7. Frequency-domain searching algorithm in deflectometry for measuring the surface of a transparent planar element — Optics Letters (2024).
   _{Wanxing Zheng; Dahai Li; Ruiyang Wang; Zekun Zhang; Renhao Ge; Manwei Chen}

8. Refractive index measurement deflectometry for measuring gradient refractive index lens — Optics Express (2024).
   _{Zekun Zhang; Ruiyang Wang; Xinwei Zhang; Renhao Ge; Wanxing Zheng; Manwei Chen; Dahai Li}

9. An Iterative High-Precision Algorithm for Multi-Beam Array Stitching Method Based on Scanning Hartmann — Applied Sciences (2024).
   _{Xiangyu Yan; Dahai Li; Kewei E; Fang Feng; Tao Wang; Xun Xue; Zekun Zhang; Kai Lu}

10. Density field measurement deflectometry for supersonic wind tunnels — Optics Letters (2023).
    _{Xinwei Zhang; Dahai Li; Zekun Zhang; Baolong Huang; Ruiyang Wang; Hongyu Pu; Zhenxin Huang; Zhi Chen}

1. Deflectometry for Planar Surfaces with Camera Lens Entrance Pupil Calibration — 2023 2nd International Conference on Optical Imaging and Measurement (ICOIM) (2023).
   _{Renhao Ge; Dahai Li; Ruiyang Wang; Wanxing Zheng; Zekun Zhang}

2. Quantitative Flow Fields Visualization Based on Deflectometry — 2023 2nd International Conference on Optical Imaging and Measurement (ICOIM) (2023).
   _{Zekun Zhang; Dahai Li; Xinwei Zhang; Ruiyang Wang; Renhao Ge; Wanxing Zheng}

Open to conversations about optical metrology, inverse problems, computational imaging, and scientific software.