2018/04/13 by Chensheng Wu, Robert Lee, Wu, Chensheng +4
Computer Science · Physics and Astronomy · #Advanced Optical Sensing Technologies #Applied Physics (physics.app-ph) #Artificial intelligence #Asymmetry #Computer science #FOS: Computer and information sciences #FOS: Physical sciences #Geology #Image Enhancement Techniques #Information Retrieval (cs.IR) #Laser #Lidar #Light scattering #Object detection #Optics #Optics (physics.optics) #Physics #Profiling (computer programming) #Radar #Random lasers and scattering media #Scattering #Telecommunications #Underwater #Waveform #cs.IR #physics.app-ph #physics.optics
paper · pdf · doi:10.48550/arxiv.1804.05118
published in arXiv (Cornell University) (Cornell University)
arxiv created 2018/04/13 · openalex publication_date 2018/04/13 · arxiv updated 2018/04/17 · openalex created_date 2018/04/24 · openalex updated_date 2026/08/06
The scattering of light observed through the turbid underwater channel is often regarded as the leading challenge when designing underwater electro-optical imaging systems. There have been many approaches to address the effects of scattering such as using pulsed laser sources to reject scattered light temporally, or using intensity modulated waveforms and matched filters to remove the scattered light spectrally. In this paper, a new method is proposed which primarily uses the backscattering asymmetry property for object detection and geometric profiling. In our approach, two parallel and identical continuous wave (CW) laser beams with narrow beam widths (~2mm) are used as active illumination sources. The two beams also have controllable spacing and aiming angle, as well as initial phase difference for convenience of scanning and profiling a target. Through theory and experimental results, it will be shown that when an object leans or tilts towards one of the beam's central trajectory, the asymmetry in the backscattered signals can be used to indicate the location or slope of the target's surface, respectively. By varying the spacing or aiming angle of the two beams, a number of surface samples can be collected to reconstruct the object's shape geometrically. The resolution and range limit of our approach are also measured and reported in this work. In application, our proposed method provides an economic solution to perform imaging through turbid underwater environments. Additionally, the idea can be combined with the pulsed or modulated laser signals for enhanced imaging results.