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arXiv · 1512.06539

Spatial Phase-Sweep: Increasing temporal resolution of transient imaging using a light source array

Ryuichi Tadano·Adithya Kumar Pediredla·Kaushik Mitra·Ashok Veeraraghavan
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Abstract

Transient imaging or light-in-flight techniques capture the propagation of an ultra-short pulse of light through a scene, which in effect captures the optical impulse response of the scene. Recently, it has been shown that we can capture transient images using commercially available Time-of-Flight (ToF) systems such as Photonic Mixer Devices (PMD). In this paper, we propose `spatial phase-sweep', a technique that exploits the speed of light to increase the temporal resolution beyond the 100 picosecond limit imposed by current electronics. Spatial phase-sweep uses a linear array of light sources with spatial separation of about 3 mm between them, thereby resulting in a time shift of about 10 picoseconds, which translates into 100 Gfps of transient imaging in theory. We demonstrate a prototype and transient imaging results using spatial phase-sweep.

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Ryuichi Tadano, Adithya Kumar Pediredla, Kaushik Mitra, Ashok Veeraraghavan. 2015-12-21. Spatial Phase-Sweep: Increasing temporal resolution of transient imaging using a light source array. https://arxiv.org/abs/1512.06539

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