Synthetic Wavelength Holography

Synthetic Wavelength Holography

Imaging through scattering media or around corners at high resolution

Synthetic Wavelength Holography introduces a novel solution to image hidden objects through scatterers or non-line-of-sight geometries at the physical space bandwidth limit. Current state-of-the-art approaches are either technically limited by the low spatial and temporal resolution of time-of-flight detectors, or by a very narrow viewing angle in which the hidden object can be reconstructed. In our approach, we utilize frequency heterodyning to beat together light at two closely spaced optical frequencies to produce a low frequency ‘synthetic wave’ (beat wave), largely immune to the unknown scattering processes between hidden object and detector. By applying the latest full-field lock-in detector technology, we are able to capture a ‘synthetic hologram’ of the hidden object within milliseconds. Since the ‘synthetic wavelength’ is freely tunable, the captured hologram provides a window to fully reconstruct the three-dimensional light field of the hidden scene at at high space-bandwidth.

The general concept of ‘synthetic waves’ has potential applications at many different scales and wavebands, including radar, ultrasound, or X-ray. In the optical waveband the ability to look around corners or through scattering media has many potential applications in medicine, naval sciences, earth, and planetary sciences as well as automotive sensing and material sciences. Looking deeper through tissue, novel endoscopic imaging methods, or imaging through dense fog or atmospheric turbulences are just a few potential applications.

See this Preprint for more information.




F. Willomitzer
Synthetic Wavelength Holography – Imaging around Corners and through Scattering Media at the Physical Space-Bandwidth Limit
Physics Colloquium Talk Series, University Erlangen-Nuremberg, Germany, 2021
[Full Video]
F. Willomitzer
Fundamental Limits in Computational 3D Imaging – From Novel 3D Cameras to Looking around Corners
Beyond the Patterns Talk Series, University Erlangen-Nuremberg, Germany, 2021
[Full Video] , [Jump to Project (23:42)]

Publications

Synthetic Wavelength Holography: Snapshot Non-Line-of-Sight Imaging with High-Resolution and Wide Field of View
F. Willomitzer, P. Rangarajan, F. Li, M. Balaji, M. Christensen, O. Cossairt.
Accepted in Nature Communications (Preprint on Research Square)

Synthetic Wavelength Holography: An Extension of Gabor’s Holographic Principle to Imaging with Scattered Wavefronts
F. Willomitzer, P. Rangarajan, F. Li, M. Balaji, M. Christensen, O. Cossairt.
arXiv Preprint

Spatially resolved Indirect Imaging of objects beyond the line of sight
P. Rangarajan, F. Willomitzer, O. Cossairt, MP. Christensen
Proc. SPIE 11135, Unconventional and Indirect Imaging, Image Reconstruction, and Wavefront Sensing 2019

Non-Line-of-Sight Imaging with Superheterodyne Remote Digital Holography
F. Willomitzer, F. Li, M.M. Balaji, P. Rangarajan, O. Cossairt
OSA Computational Optical Sensing and Imaging, CM2A. 2

Non-Line-of-Sight Imaging using Superheterodyne Interferometry
F. Willomitzer, F. Li, M.M. Balaji, P. Rangarajan, O. Cossairt.
OSA Computational Optical Sensing and Imaging, CM2E. 1

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Florian Willomitzer
Research Assistant Professor