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arXiv · 2008.10358

Swept Source Lidar: simultaneous FMCW ranging and nonmechanical beam steering with a wideband swept source

Masayuki Okano·Changho Chong
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Abstract

Light detection and ranging (lidar) has long been used in various applications. Solid-state beam steering mechanisms are needed for robust lidar systems. Here we propose and demonstrate a lidar scheme called "Swept Source Lidar" that allows us to perform frequency-modulated continuous-wave (FMCW) ranging and nonmechanical beam steering simultaneously. Wavelength dispersive elements provide angular beam steering, while a laser frequency is continuously swept by a wideband swept source over its whole tuning bandwidth. Employing a tunable vertical-cavity surface-emitting laser and a 1-axis mechanical beam scanner, three-dimensional point cloud data has been obtained. Swept Source Lidar systems can be flexibly combined with various beam steering elements to realize full solid-state FMCW lidar systems.

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Masayuki Okano, Changho Chong. 2020-07-31. Swept Source Lidar: simultaneous FMCW ranging and nonmechanical beam steering with a wideband swept source. https://doi.org/10.1364/oe.396707

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