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.
Structured light illumination is an active three-dimensional scanning technique that uses a projector and camera pair to project and capture a series of stripe patterns; however, with a single camera and single projector, structured light scanning has issues associated with scan occlusions, multi-path, and weak signal reflections. To address these issues, this paper proposes dual-projector scanning using a range of projector/camera arrangements. Unlike previous attempts at dual-projector scanning, the proposed scanner drives both light engines simultaneously, using temporal-frequency multiplexing to computationally decouple the projected patterns. Besides presenting the details of how such a system is built, we also present experimental results demonstrating how multiple projectors can be used to (1) minimize occlusions; (2) achieve higher signal-to-noise ratios having twice a single projector’s brightness; (3) reduce the number of component video frames required for a scan; and (4) detect multi-path interference.
more » « less- NSF-PAR ID:
- 10131772
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Applied Optics
- Volume:
- 59
- Issue:
- 4
- ISSN:
- 1559-128X; APOPAI
- Format(s):
- Medium: X Size: Article No. 964
- Size(s):
- Article No. 964
- Sponsoring Org:
- National Science Foundation
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