For conventional laser range-gated underwater imaging （RG[） systems, the target image is obtained based oil the reflective character of the target. One of the main performance limiting factors of conventional RGI is...For conventional laser range-gated underwater imaging （RG[） systems, the target image is obtained based oil the reflective character of the target. One of the main performance limiting factors of conventional RGI is that, when the underwater target has the same reflectivity as the background, it is difficult to distinguish the target from the background. An improvement is to use the polarization components of the reflected light. On the basis of conventional RGI, we propose a polarimetric RGI system that employs a polarization generator and a polarization analyzer to detect and recognize underwater objects. Experimental results demonstrate that, by combining polarization with intensity information, we are better able to enhance identification of the underwater target from other objects of the same reflectivity.展开更多
Range-gated imaging has the advantages of long imaging distance,high signal-to-noise ratio,and good environmental adaptability.However,conventional range-gated imaging utilizes a single laser pulse illumination modali...Range-gated imaging has the advantages of long imaging distance,high signal-to-noise ratio,and good environmental adaptability.However,conventional range-gated imaging utilizes a single laser pulse illumination modality,which can only resolve a single depth of ranging in one shot.Three-dimensional(3D)imaging has to be obtained from multiple shots,which limits its real-time performance.Here,an approach of range-gated imaging using a specific double-pulse sequence is proposed to overcome this limitation.With the help of a calibrated double-pulse range-intensity profile,the depth of static targets can be calculated from the measurement of a single shot.Moreover,the double-pulse approach is beneficial for real-time depth estimation of dynamic targets.Experimental results indicate that,compared to the conventional approach,the depth of field and depth resolution are increased by 1.36 and 2.20 times,respectively.It is believed that the proposed double-pulse approach provides a potential new paradigm for range-gated 3D imaging.展开更多
According to the study of super-resolution range-gated system, we proposed an improved system with linear plus detects. And a range function is derived by considering the shot effect noise and dark current noise. The ...According to the study of super-resolution range-gated system, we proposed an improved system with linear plus detects. And a range function is derived by considering the shot effect noise and dark current noise. The simulation shows that the improved system has a good range accuracy capability.展开更多
We present a range-gating delayed detection super-resolution imaging Iidar with high accuracy based on the signal intensities of three consecutive delay samples. The system combines the range and signal intensity info...We present a range-gating delayed detection super-resolution imaging Iidar with high accuracy based on the signal intensities of three consecutive delay samples. The system combines the range and signal intensity information from multi-pulse detections to calculate the pulse peak position under the assumption of a Gaussian pulse shape. Experimental results indicate that the proposed algorithm effectively calculates pulse peak position and exhibits excellent accuracy with super-resolution. Accuracy analysis shows that accuracy is best improved by enhancing signal-to-noise ratio, strategically selecting samples, reducing pulse width, and appropriately choosing the delayed periods between samples.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 61205187the China Postdoctoral Science Foundation under Grant No 2012M510217
文摘For conventional laser range-gated underwater imaging （RG[） systems, the target image is obtained based oil the reflective character of the target. One of the main performance limiting factors of conventional RGI is that, when the underwater target has the same reflectivity as the background, it is difficult to distinguish the target from the background. An improvement is to use the polarization components of the reflected light. On the basis of conventional RGI, we propose a polarimetric RGI system that employs a polarization generator and a polarization analyzer to detect and recognize underwater objects. Experimental results demonstrate that, by combining polarization with intensity information, we are better able to enhance identification of the underwater target from other objects of the same reflectivity.
基金supported by the National Key Research and Development Program of China(No.2022YFC2807702)the National Natural Science Foundation of China(No.12274262)+2 种基金the Sino-German Center Mobility Programs(No.M-0044)the State Key Laboratory of Precision Measurement Technology and Instruments(No.pilab2205)the Shandong University Inter-discipline Research Grant,Jinan Government Project(No.202228042).
文摘Range-gated imaging has the advantages of long imaging distance,high signal-to-noise ratio,and good environmental adaptability.However,conventional range-gated imaging utilizes a single laser pulse illumination modality,which can only resolve a single depth of ranging in one shot.Three-dimensional(3D)imaging has to be obtained from multiple shots,which limits its real-time performance.Here,an approach of range-gated imaging using a specific double-pulse sequence is proposed to overcome this limitation.With the help of a calibrated double-pulse range-intensity profile,the depth of static targets can be calculated from the measurement of a single shot.Moreover,the double-pulse approach is beneficial for real-time depth estimation of dynamic targets.Experimental results indicate that,compared to the conventional approach,the depth of field and depth resolution are increased by 1.36 and 2.20 times,respectively.It is believed that the proposed double-pulse approach provides a potential new paradigm for range-gated 3D imaging.
文摘According to the study of super-resolution range-gated system, we proposed an improved system with linear plus detects. And a range function is derived by considering the shot effect noise and dark current noise. The simulation shows that the improved system has a good range accuracy capability.
文摘We present a range-gating delayed detection super-resolution imaging Iidar with high accuracy based on the signal intensities of three consecutive delay samples. The system combines the range and signal intensity information from multi-pulse detections to calculate the pulse peak position under the assumption of a Gaussian pulse shape. Experimental results indicate that the proposed algorithm effectively calculates pulse peak position and exhibits excellent accuracy with super-resolution. Accuracy analysis shows that accuracy is best improved by enhancing signal-to-noise ratio, strategically selecting samples, reducing pulse width, and appropriately choosing the delayed periods between samples.
