An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were reported.The camera achieved a temporal resolution of 10 ps by using a pulse-dilation devi...An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were reported.The camera achieved a temporal resolution of 10 ps by using a pulse-dilation device and gated MCP imager,and a spatial resolution of 100μm by using an electronic imaging system comprising combined magnetic lenses.The spatial resolution characteristics of the camera were studied both theoretically and experimentally.The results showed that the camera with combined magnetic lenses reduced the field curvature and acquired a larger working area.A working area with a diameter of 53 mm was created by applying four magnetic lenses to the camera.Furthermore,the camera was used to detect the X-rays produced by the laser-targeting device.The diagnostic results indicated that the width of the X-ray pulse was approximately 18 ps.展开更多
使用卷帘快门相机进行移动测量时,由于逐行曝光的特点,影像上会产生果冻效应。而传统的运动恢复结构(Structure from Motion,SfM)算法假设影像是全局快门获取,直接处理卷帘快门影像很难得到高精度的结果。针对以上问题,构建了卷帘快门Sf...使用卷帘快门相机进行移动测量时,由于逐行曝光的特点,影像上会产生果冻效应。而传统的运动恢复结构(Structure from Motion,SfM)算法假设影像是全局快门获取,直接处理卷帘快门影像很难得到高精度的结果。针对以上问题,构建了卷帘快门SfM框架,主要包括对初始化重建、卷帘快门影像绝对位姿估计、卷帘快门三角化和光束法平差等关键步骤的算法改进,分析并验证了卷帘快门SfM的退化问题,提出利用多镜头组合相机采集的影像进行卷帘快门SfM可以避免退化,并且利用多镜头约束的光束法平差对SfM结果进行进一步优化。实验表明,所提出的面向多镜头组合相机的卷帘快门SfM算法能够有效应对果冻效应,提高重建精度。展开更多
基金National Natural Science Foundation of China(NSFC)(No.11775147)Guangdong Basic and Applied Basic Research Foundation(Nos.2019A1515110130 and 2024A1515011832)+1 种基金Shenzhen Key Laboratory of Photonics and Biophotonics(ZDSYS20210623092006020)Shenzhen Science and Technology Program(Nos.JCYJ20210324095007020,JCYJ20200109105201936 and JCYJ20230808105019039).
文摘An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were reported.The camera achieved a temporal resolution of 10 ps by using a pulse-dilation device and gated MCP imager,and a spatial resolution of 100μm by using an electronic imaging system comprising combined magnetic lenses.The spatial resolution characteristics of the camera were studied both theoretically and experimentally.The results showed that the camera with combined magnetic lenses reduced the field curvature and acquired a larger working area.A working area with a diameter of 53 mm was created by applying four magnetic lenses to the camera.Furthermore,the camera was used to detect the X-rays produced by the laser-targeting device.The diagnostic results indicated that the width of the X-ray pulse was approximately 18 ps.
文摘使用卷帘快门相机进行移动测量时,由于逐行曝光的特点,影像上会产生果冻效应。而传统的运动恢复结构(Structure from Motion,SfM)算法假设影像是全局快门获取,直接处理卷帘快门影像很难得到高精度的结果。针对以上问题,构建了卷帘快门SfM框架,主要包括对初始化重建、卷帘快门影像绝对位姿估计、卷帘快门三角化和光束法平差等关键步骤的算法改进,分析并验证了卷帘快门SfM的退化问题,提出利用多镜头组合相机采集的影像进行卷帘快门SfM可以避免退化,并且利用多镜头约束的光束法平差对SfM结果进行进一步优化。实验表明,所提出的面向多镜头组合相机的卷帘快门SfM算法能够有效应对果冻效应,提高重建精度。
