Review of Optical-based Detection Technology for Underwater Small Targets

CHEN Qingyan; WU Guojun; WU Yafeng; MIAO Yuhong

doi:10.11993/j.issn.2096-3920.2026-0049

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CHEN Qingyan, WU Guojun, WU Yafeng, MIAO Yuhong. Review of Optical-based Detection Technology for Underwater Small Targets[J]. Journal of Unmanned Undersea Systems. doi: 10.11993/j.issn.2096-3920.2026-0049

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CHEN Qingyan, WU Guojun, WU Yafeng, MIAO Yuhong. Review of Optical-based Detection Technology for Underwater Small Targets[J]. Journal of Unmanned Undersea Systems. doi: 10.11993/j.issn.2096-3920.2026-0049

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Review of Optical-based Detection Technology for Underwater Small Targets

doi: 10.11993/j.issn.2096-3920.2026-0049

Shaanxi Key Laboratory of Ocean Optics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China

Received Date: 2026-03-06
Accepted Date: 2026-04-20
Rev Recd Date: 2026-04-15

Available Online: 2026-05-26

Abstract

Abstract

Accurate detection and recognition of underwater small targets (e.g., micro underwater vehicles, underwater detection device etc.) constitute a critical component in the fields of marine resource exploitation, underwater security early warning, and underwater engineering inspection. Constrained by the combined effects of water body attenuation, optical scattering, acoustic multipath effect, and complex background noise, traditional detection technologies exhibit notable limitations in terms of effective detection range, spatial resolution, and real-time responsiveness. With the advancement of marine development toward refinement and intelligence, coupled with the increasingly prominent strategic value of underwater unmanned equipment countermeasures, optical detection technology for underwater small targets has emerged as a research hotspot in the domain of marine information technology. This paper systematically sorts out the research background and strategic significance of optical detection technology for underwater small targets, and presents a comprehensive review focusing on two major technical approaches: image-based and LiDAR-based methods. For the image-based technical system, the study centers on two core modules—image enhancement and target detection—and conducts an in-depth analysis of the principle mechanism, improvement strategies, and performance characteristics of various technologies. For the LiDAR-based technical system, aiming at detection modes including area-scan imaging, point-scan imaging, and line-scan imaging, the paper systematically elaborates on their technical features and typical application scenarios. Furthermore, this paper analyzes the bottleneck problems faced by existing technologies, and prospects future research directions in combination with the development trend of marine technology, so as to provide theoretical support and practical reference for the engineering implementation of optical detection technology for underwater small targets.
- underwater small targets,
- optical detection,
- image enhancement,
- LiDAR

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References(62)

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