Light transport contains all light information between a light source and an image sensor. As an important application of light transport, dual photography has been a popular research topic, but it is challenged by long acquisition time, low signal-to-noise ratio, and the storage or processing of a large number of measurements. In this Letter, we propose a novel hardware setup that combines a flying-spot micro-electro mechanical system (MEMS) modulated projector with an event camera to implement dual photography for 3D scanning in both line-of-sight (LoS) and non-line-of-sight (NLoS) scenes with a transparent object. In particular, we achieved depth extraction from the LoS scenes and 3D reconstruction of the object in a NLoS scene using event light transport.
Non-Line-Of-Sight (NLOS) imaging aims at recovering the 3D geometry of objects that are hidden from the direct line of sight. One major challenge with this technique is the weak available multibounce signal limiting scene size, capture speed, and reconstruction quality. To overcome this obstacle, we introduce a multipixel time-of-flight non-line-of-sight imaging method combining specifically designed Single Photon Avalanche Diode (SPAD) array detectors with a fast reconstruction algorithm that captures and reconstructs live low-latency videos of non-line-of-sight scenes with natural non-retroreflective objects. We develop a model of the signal-to-noise-ratio of non-line-of-sight imaging and use it to devise a method that reconstructs the scene such that signal-to-noise-ratio, motion blur, angular resolution, and depth resolution are all independent of scene depth suggesting that reconstruction of very large scenes may be possible.
more » « less- NSF-PAR ID:
- 10306359
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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