scholarly journals Thermoacoustic imaging over large field of view for three-dimensional breast tumor localization: A phantom study

2014 ◽  
Vol 41 (11) ◽  
pp. 110701 ◽  
Author(s):  
Yong Fu ◽  
Zhong Ji ◽  
Wenzheng Ding ◽  
Fanghao Ye ◽  
Cunguang Lou
2011 ◽  
Author(s):  
Meijing Gao ◽  
Weilong Wu ◽  
Haihua Gu ◽  
Weihong Bi

2014 ◽  
Vol 2014 ◽  
pp. 1-16 ◽  
Author(s):  
Chong Wang ◽  
Zheng You ◽  
Fei Xing ◽  
Borui Zhao ◽  
Bin Li ◽  
...  

It has been discovered that image motions and optical flows usually become much more nonlinear and anisotropic in space-borne cameras with large field of view, especially when perturbations or jitters exist. The phenomenon arises from the fact that the attitude motion greatly affects the image of the three-dimensional planet. In this paper, utilizing the characteristics, an optical flow inversion method is proposed to treat high-accurate remote sensor attitude motion measurement. The principle of the new method is that angular velocities can be measured precisely by means of rebuilding some nonuniform optical flows. Firstly, to determine the relative displacements and deformations between the overlapped images captured by different detectors is the primary process of the method. A novel dense subpixel image registration approach is developed towards this goal. Based on that, optical flow can be rebuilt and high-accurate attitude measurements are successfully fulfilled. In the experiment, a remote sensor and its original photographs are investigated, and the results validate that the method is highly reliable and highly accurate in a broad frequency band.


1992 ◽  
Vol 8 (2) ◽  
pp. 145-151 ◽  
Author(s):  
Rosa M. Angulo ◽  
Jesús Dapena

This study compared the errors produced with 3-D video and film analysis techniques using the DLT method with fixed cameras when the images cover a wide field of view. The results indicated that with a large field of view (8 meters) the accuracy of video analysis is clearly inferior to that of film analysis. However, within the volume of the control object, both film and video analyses are still precise enough for most practical purposes. Errors were larger in landmarks outside the control object than in the points of the control object. The maximum errors in the calculated positions of external landmarks were particularly large in the video analysis. However, even these rather large errors for points markedly outside the control object may be acceptable. It will depend on the requirements of each particular investigation.


Sensors ◽  
2020 ◽  
Vol 20 (10) ◽  
pp. 2842 ◽  
Author(s):  
Zhanpeng Xu ◽  
Erik Forsberg ◽  
Yang Guo ◽  
Fuhong Cai ◽  
Sailing He

A novel light-sheet microscopy (LSM) system that uses the laser triangulation method to quantitatively calculate and analyze the surface topography of opaque samples is discussed. A spatial resolution of at least 10 μm in z-direction, 10 μm in x-direction and 25 μm in y-direction with a large field-of-view (FOV) is achieved. A set of sample measurements that verify the system′s functionality in various applications are presented. The system has a simple mechanical structure, such that the spatial resolution is easily improved by replacement of the objective, and a linear calibration formula, which enables convenient system calibration. As implemented, the system has strong potential for, e.g., industrial sample line inspections, however, since the method utilizes reflected/scattered light, it also has the potential for three-dimensional analysis of translucent and layered structures.


2017 ◽  
Vol 37 (2) ◽  
pp. 0215002
Author(s):  
简慧杰 Jian Huijie ◽  
何建争 He Jianzheng ◽  
王克逸 Wang Keyi

2020 ◽  
Author(s):  
Andreas Bodén ◽  
Francesca Pennacchietti ◽  
Ilaria Testa

AbstractThe volumetric architecture of organelles and molecules inside cells can only be investigated with microscopes featuring sufficiently high resolving power in all three spatial dimensions. Current methods suffer from severe limitations when applied to live cell imaging such as long recording times and/or photobleaching. By introducing a novel optical scheme to switch reversibly switchable fluorescent molecules, we demonstrate volumetric nanoscopy of living cells with resolution below 100 nm in 3D, large field of view and minimal illumination intensities (W-kW/cm2).


MRS Advances ◽  
2018 ◽  
Vol 3 (39) ◽  
pp. 2341-2346 ◽  
Author(s):  
Scott Annett ◽  
Sergio Morelhao ◽  
Darren Dale ◽  
Stefan Kycia

AbstractThree dimensional X-ray diffraction (3DXRD) microscopy is a powerful technique that provides crystallographic and spatial information of a large number, of the order of thousands, of crystalline grains in a sample simultaneously. A key component of every 3DXRD microscopy experiment is the near field detector that provides high resolution spatial information of the grains. In this work we present a novel design for a semi-transparent, 16 megapixel near field detector. As opposed to a typical single scintillator phosphor detector, this design, we call the Quad Near Field Detector, uses four quadrants. It has a total field of view is 5.3 mm x 5.3 mm with an effective pixel size of 1.3 µm x 1.3 µm. The detector’s relatively large field of view can be used to obtain higher order diffraction spots which we anticipate will lead to improved spatial resolution in grain reconstructions. The large field of view can also enable the detector to be positioned further from the sample, in this way increasing the working distance and enabling larger environmental cells for in-situ studies. Many alignment parameters can be resolved by careful mechanical design. For this reason a novel translation stage for focusing the microscopes was developed, tested, and implemented. The near field detector was calibrated and characterized at the Cornell High Energy Synchrotron Source. The operational feasibility of such a multi-plate detector demonstrated in this work paves the way for new technologies in instrumentation of 3DXRD microscopy.


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