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Wavefront coding for visual optics
Third International Conference on Applications of Optics and Photonics, 2017Wavefront coding (WFC) enables the depth of field of incoherent optical systems to be extended. This method involves a cubic-phase plate in the system yielding a blurred image nearly invariant to defocus. In visual optics there is a big interest in improving solutions for two different problems: Presbyopia correction and high resolution retinal images ...
Eva Acosta, Justo Arinês
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Combination of color coding and wavefront coding for extended depth of field
Optics Communications, 2017Abstract Color coding has been experimentally demonstrated to be able to extend the depth of field (DoF) of an imaging system in single snapshot. A numerical model is adopted in this paper to quantitatively characterize its imaging properties (strehl ratio, point spread function and modulation transfer function).
Fenglin Xian, Chunjie Zhai
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Applications of wavefront coded imaging
SPIE Proceedings, 2004Imaging systems using aspheric imaging lenses with complementary computation can deliver performance unobtainable in conventional imaging systems. These new imaging systems, termed Wavefront coded imaging systems, use specialized optics to capture a coded image of the scene.
Ramkumar Narayanswamy +3 more
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Spatial coding with curved wavefronts
IEEE Ultrasonics Symposium, 2004, 2005Curved wavefronts of unfocused beams can be viewed as spatial codes that can be decoded to produce high quality images. The decoding process can be performed by spatial matched or Wiener filtering methods that are a generalization of synthetic receive processing for large apertures rather than small elements.
R. Zemp, M.F. Insana
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Wavefront coding with adaptive optics
SPIE Proceedings, 2015We have implemented an extended depth of field optical system by wavefront coding with a micromachined membrane deformable mirror. This approach provides a versatile extension to standard wavefront coding based on fixed phase mask. First experimental results validate the feasibility of the use of adaptive optics for variable depth wavefront coding in ...
Temitope E. Agbana +5 more
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Compact vortex wavefront coding camera
Computational Imaging V, 2020We experimentally design, construct and test a compact optical system featuring a vortex diffractive waveplate placed in the aperture stop of the lens system. The wavefront coding camera diffracts polarized coherent illumination in the system's focal plane and reduces the peak intensity of the beam by two orders of magnitude while simultaneously ...
Kyle Novak, Abbie T. Watnik
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The design of wavefront coded imaging system
SPIE Proceedings, 2016Wavefront Coding is a new method to extend the depth of field, which combines optical design and signal processing together. By using optical design software ZEMAX ,we designed a practical wavefront coded imaging system based on a conventional Cooke triplet system .Unlike conventional optical system, the wavefront of this new system is modulated by a ...
Shun Lan, Zhaofeng Cen, Xiaotong Li
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Wavefront decoding of trellis codes
Proceedings of 1995 IEEE International Symposium on Information Theory, 2002A novel reduced-complexity trellis decoding algorithm is described. The new algorithm, called wavefront decoding (WD), avoids the throughput bottleneck caused by metric and state-information feedback, which characterizes previously known breadth-first decoding algorithms.
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The Simulation of Wavefront Coding Imaging Systems
2007 IEEE International Conference on Integration Technology, 2007In the domain of reconnaissance, remote sensing, etc., people want to get high resolution images. There is a conflict between the resolution and the optical system defocus. In order to acquire high resolution images, some methods are taken to minish the defocus, but these ways affect the cost and weight of the system.
Hui Bin +3 more
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Optimized restoration of wavefront coded images
SPIE Proceedings, 2014Wavefront coding (WFC) uses a special aspheric optics and digital image processing to extend the depth of focus in imaging systems. An intermediate blurred image is generated by the spatial convolution of the image with the point spread function (PSF) of a cubic phase mask. Restoration tests are performed on an optically encoded image.
C. Toxqui-Quitl +3 more
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