Journals > > Topics > Digital Holography
Digital Holography|4 Article(s)
Control and image processing for streak tube imaging lidar based on VB and MATLAB
Zhaoshuo Tian, Zihao Cui, Liting Zhang, Tianci Xu, Yanchao Zhang, and Shiyou Fu
In this letter, we develope a control and image processing system for Streak Tube Imaging Lidar (STIL). In the system, the data acquisition card control and the software interface are programmed in Visual Basic (VB) while the image processing is finished by MATLAB. A STIL imaging experiment is carried out in the laboratory. We obtained the intensity and range images of targets with pseudo color by image processing and reconstruction for a set of raw streak images of targets at different distances acquired by STIL. The range resolution is better than 2 centimeters. In this letter, we develope a control and image processing system for Streak Tube Imaging Lidar (STIL). In the system, the data acquisition card control and the software interface are programmed in Visual Basic (VB) while the image processing is finished by MATLAB. A STIL imaging experiment is carried out in the laboratory. We obtained the intensity and range images of targets with pseudo color by image processing and reconstruction for a set of raw streak images of targets at different distances acquired by STIL. The range resolution is better than 2 centimeters.
Chinese Optics Letters
- Publication Date: May. 30, 2014
- Vol. 12, Issue 6, 060015 (2014)
3D dif fractive lenses to overcome the 3D Abbe subwavelength dif fraction limit
Igor Minin, and Oleg Minin
The innovative radiating structures as a conical millimeter wave FZP lens are proposed for subwavelength focusing. The results of FDTD simulation and experimental verification are discussed. It has been shown that in contrast to the flat diffractive optics the curvilinear 3D diffractive conical optics is capable of overcoming 3D Abbe barrier with a focal distance F greater than 2. The focal intensity distribution for such type of lenses is not circularly symmetric and thus the focal spot in the high numerical aperture case is no longer an Airy pattern. These results may find useful applications in optical microscopes, including "reverse-microscope", nondestructive testing, microoptics, and nanooptics. The innovative radiating structures as a conical millimeter wave FZP lens are proposed for subwavelength focusing. The results of FDTD simulation and experimental verification are discussed. It has been shown that in contrast to the flat diffractive optics the curvilinear 3D diffractive conical optics is capable of overcoming 3D Abbe barrier with a focal distance F greater than 2. The focal intensity distribution for such type of lenses is not circularly symmetric and thus the focal spot in the high numerical aperture case is no longer an Airy pattern. These results may find useful applications in optical microscopes, including "reverse-microscope", nondestructive testing, microoptics, and nanooptics.
Chinese Optics Letters
- Publication Date: May. 30, 2014
- Vol. 12, Issue 6, 060014 (2014)
Twin-image problem in digital holography—a survey (Invited Paper)
Elena Stoykova, Hoonjong Kang, and Jiyung Park
Zero-order and twin images are a serious obstacle in achieving a high-quality output in in-line digital holography (DH). They decrease the useful bandwidth of the off-axis DH. Over the years the twin image removal problem was approached both by instrumental and numerical means. The paper provides an extended survey of the proposed solutions with their pros and cons as a guide for further advance in this field. Processing of a single spatial carrier fringe pattern involves spatial filtering in the frequency domain, spatial phase-shifting (PS) or wavelet transform. A point source digital holographic microscopy (DHM), introduction of calibration measurements or various modifications of PS technique are instrumental solutions to the twin image problem for in-line DH. Numerical solutions to the same problem include iterative and non-iterative approaches, diffraction-based and inverse problem solutions, reconstruction of purely real or phase objects and of complex objects, reconstruction of plane and volume objects. Elimination only of the zero-order image relies on non-linear filtering or additional calibration measurements. Zero-order and twin images are a serious obstacle in achieving a high-quality output in in-line digital holography (DH). They decrease the useful bandwidth of the off-axis DH. Over the years the twin image removal problem was approached both by instrumental and numerical means. The paper provides an extended survey of the proposed solutions with their pros and cons as a guide for further advance in this field. Processing of a single spatial carrier fringe pattern involves spatial filtering in the frequency domain, spatial phase-shifting (PS) or wavelet transform. A point source digital holographic microscopy (DHM), introduction of calibration measurements or various modifications of PS technique are instrumental solutions to the twin image problem for in-line DH. Numerical solutions to the same problem include iterative and non-iterative approaches, diffraction-based and inverse problem solutions, reconstruction of purely real or phase objects and of complex objects, reconstruction of plane and volume objects. Elimination only of the zero-order image relies on non-linear filtering or additional calibration measurements.
Chinese Optics Letters
- Publication Date: May. 20, 2014
- Vol. 12, Issue 6, 060013 (2014)
Digital holographic microscopy for automated 3D cell identification: an overview (Invited Paper)
Arun Anand, and Bahram Javidi
Digital holographic (DH) microscopy is a promising technique for quantitative phase contrast imaging. It provides complex amplitude of the object wavefront, which in turn yields the thickness distribution of the object. An added advantage of the technique is its ability for numerical focusing, which provides the thickness distribution of the object at different axial planes. In this invited paper, we present an overview of our reported work on two beam DH microscopyto acquire different cell parameters for cell imaging and automated cell identification. Applications to automated monitoring of stem cells without destroying the cells and automated identification of malaria infected red blood cells are discussed. Digital holographic (DH) microscopy is a promising technique for quantitative phase contrast imaging. It provides complex amplitude of the object wavefront, which in turn yields the thickness distribution of the object. An added advantage of the technique is its ability for numerical focusing, which provides the thickness distribution of the object at different axial planes. In this invited paper, we present an overview of our reported work on two beam DH microscopyto acquire different cell parameters for cell imaging and automated cell identification. Applications to automated monitoring of stem cells without destroying the cells and automated identification of malaria infected red blood cells are discussed.
Chinese Optics Letters
- Publication Date: May. 30, 2014
- Vol. 12, Issue 6, 060012 (2014)
Topics
© Copyright 2018-2021 | Chinese Laser Press. All Rights Reserved 沪ICP备15018463号-20