The most important optical component in an optical fiber endoscope is its objective lens.To achieve a high imaging performance level,the development of an ultra-compact objective lens is thus the key to an ultra-thin ...The most important optical component in an optical fiber endoscope is its objective lens.To achieve a high imaging performance level,the development of an ultra-compact objective lens is thus the key to an ultra-thin optical fiber endoscope.In this work,we use femtosecond laser 3D printing to develop a series of micro objective lenses with different optical designs.The imaging resolution and field-of-view performances of these printed micro objective lenses are investigated via both simulations and experiments.For the first time,multiple micro objective lenses with different fields of view are printed on the end face of a single imaging optical fiber,thus realizing the perfect integration of an optical fiber and objective lenses.This work demonstrates the considerable potential of femtosecond laser 3D printing in the fabrication of micro-optical systems and provides a reliable solution for the development of an ultrathin fiber endoscope.展开更多
A simple yet efficient tracking framework is proposed for real-time multi-object tracking with micro aerial vehicles(MAVs). It's basic missions for MAVs to detect specific targets and then track them automatically...A simple yet efficient tracking framework is proposed for real-time multi-object tracking with micro aerial vehicles(MAVs). It's basic missions for MAVs to detect specific targets and then track them automatically. In our method, candidate regions are generated using the salient detection in each frame and then classified by an eural network. A kernelized correlation filter(KCF) is employed to track each target until it disappears or the peak-sidelobe ratio is lower than a threshold. Besides, we define the birth and death of each tracker for the targets. The tracker is recycled if its target disappears and can be assigned to a new target. The algorithm is evaluated on the PAFISS and UAV123 datasets. The results show a good performance on both the tracking accuracy and speed.展开更多
为了提高微震震源定位精度和算法鲁棒性,研究了基于到时的定位算法的目标函数构建和时空区域信息使用。仿真实验基于Numpy,采用理想到时+随机扰动来模拟生产情况。结果表明:到时定位算法中常用的L_(1)和L_(2)目标函数对实际震源存在偏...为了提高微震震源定位精度和算法鲁棒性,研究了基于到时的定位算法的目标函数构建和时空区域信息使用。仿真实验基于Numpy,采用理想到时+随机扰动来模拟生产情况。结果表明:到时定位算法中常用的L_(1)和L_(2)目标函数对实际震源存在偏离且偏离现象非常普遍。为了减轻伪震源问题,使用到时偏差的似然函数作为基础函数,聚合时空邻域的单点基础函数作为目标函数;新构建的4维区域分布算法(Distribution of 4-Dimention Area Algorithm,D4DA)在2次标定炮定位中将定位误差分别降低了14%和26%。展开更多
基金This work was supported by Shenzhen Science and Technology Program(RCYX20200714114524139,Shenzhen Key Laboratory of Ultrafast Laser Micro/Nano Manufacturing ZDSYS20220606100405013)Natural Science Foundation of Guangdong Province(2022B1515120061)National Natural Science Foundation of China(62122057,62075136).
文摘The most important optical component in an optical fiber endoscope is its objective lens.To achieve a high imaging performance level,the development of an ultra-compact objective lens is thus the key to an ultra-thin optical fiber endoscope.In this work,we use femtosecond laser 3D printing to develop a series of micro objective lenses with different optical designs.The imaging resolution and field-of-view performances of these printed micro objective lenses are investigated via both simulations and experiments.For the first time,multiple micro objective lenses with different fields of view are printed on the end face of a single imaging optical fiber,thus realizing the perfect integration of an optical fiber and objective lenses.This work demonstrates the considerable potential of femtosecond laser 3D printing in the fabrication of micro-optical systems and provides a reliable solution for the development of an ultrathin fiber endoscope.
基金Supported by the National Natural Science Foundation of China(6160303040,61433003)Yunnan Applied Basic Research Project of China(201701CF00037)Yunnan Provincial Science and Technology Department Key Research Program(Engineering)(2018BA070)
文摘A simple yet efficient tracking framework is proposed for real-time multi-object tracking with micro aerial vehicles(MAVs). It's basic missions for MAVs to detect specific targets and then track them automatically. In our method, candidate regions are generated using the salient detection in each frame and then classified by an eural network. A kernelized correlation filter(KCF) is employed to track each target until it disappears or the peak-sidelobe ratio is lower than a threshold. Besides, we define the birth and death of each tracker for the targets. The tracker is recycled if its target disappears and can be assigned to a new target. The algorithm is evaluated on the PAFISS and UAV123 datasets. The results show a good performance on both the tracking accuracy and speed.
文摘为了提高微震震源定位精度和算法鲁棒性,研究了基于到时的定位算法的目标函数构建和时空区域信息使用。仿真实验基于Numpy,采用理想到时+随机扰动来模拟生产情况。结果表明:到时定位算法中常用的L_(1)和L_(2)目标函数对实际震源存在偏离且偏离现象非常普遍。为了减轻伪震源问题,使用到时偏差的似然函数作为基础函数,聚合时空邻域的单点基础函数作为目标函数;新构建的4维区域分布算法(Distribution of 4-Dimention Area Algorithm,D4DA)在2次标定炮定位中将定位误差分别降低了14%和26%。
