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Wenyang Sun

Publications and source records attributed to Wenyang Sun.

3 recordsLinked to original sources

High-resolution volume holographic profilometry using the Viterbi algorithm.

We use the Viterbi decoding algorithm to resolve depth features beyond the nominal resolution limit of a volume holographic profilometry system. The formulation treats the truncated point-spread function as an intersymbol interference and uses surface constraints and transition constraints to reduce the computational complexity. A factor-of-5 improvement in resolution was obtained in our experimental demonstration.

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Rainbow volume holographic imaging.

We present a new form of volume holographic imaging with rainbow illumination. High depth resolution is obtained because each quasi-monochromatic band of the rainbow acts as a depth-selective confocal slit. The color slits work in parallel to achieve a wide field of view (FoV) and so the need to scan in one lateral dimension is eliminated. Our experiments demonstrated <250-micro m depth resolution over an approximately equal to 15 degree FoV at a 50-mm working distance.

Journal Article↗

Volume holographic imaging in transmission geometry.

We address the performance of transmission geometry volume holograms as depth-selective imaging elements. We consider two simple implementations using holograms recorded with spherical and plane beams. We derive the point-spread function (PSF) of these systems using volume diffraction theory and use the PSF to estimate depth resolution. Furthermore, we show that appropriately designed objective optics can significantly improve the depth resolution or the working distance of plane-wave reference holographic imaging systems. These results are confirmed experimentally and demonstrated for objects with millimeter axial features, imaged from the 5- to 50-cm range.

Journal Article↗