Journal of the European Optical Society - Rapid publications, Vol 10 (2015)
Experimental demonstration of extended depth-of-field f/1.2 visible High Definition camera with jointly optimized phase mask and real-time digital processing
Abstract
Increasing the depth of field (DOF) of compact visible high resolution cameras while maintaining high imaging performance in the DOF range is crucial for such applications as night vision goggles or industrial inspection. In this paper, we present the end-to-end design and experimental validation of an extended depth-of-field visible High Definition camera with a very small f-number, combining a six-ring pyramidal phase mask in the aperture stop of the lens with a digital deconvolution. The phase mask and the deconvolution algorithm are jointly optimized during the design step so as to maximize the quality of the deconvolved image over the DOF range. The deconvolution processing is implemented in real-time on a Field-Programmable Gate Array and we show that it requires very low power consumption. By mean of MTF measurements and imaging experiments we experimentally characterize the performance of both cameras with and without phase mask and thereby demonstrate a significant increase in depth of field of a factor 2.5, as it was expected in the design step.
© The Authors. All rights reserved. [DOI: 10.2971/jeos.2015.15046]
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Cite this articleReferences
W. Cathey, and E. Dowski, â€New paradigm for imaging systems,†Appl. Optics 41 , 6080–6092 (2002).
D. Stork, and M. Robinson, â€Theoretical foundations for joint digital-optical analysis of electro-optical imaging systems,†Appl. Optics 47, B64–B75 (2008).
F. Diaz, F. Goudail, B. Loiseaux, and J. Huignard, â€Increase in depth of field taking into account deconvolution by optimization of pupil mask,†Opt. Lett. 34, 2970–2972 (2009).
T. Vettenburg, and A. Harvey, â€Holistic optical-digital hybridimaging design: wide-field reflective imaging,†Appl. Optics 52, 3931–3936 (2013).
E. Dowski, and W. Cathey, â€Extended depth of field through wavefront coding,†Appl. Optics 34, 1859–1866 (1995).
F. Diaz, F. Goudail, B. Loiseaux, and J. Huignard, â€Comparison of depth-of-focus-enhancing pupil masks based on a signal-to-noiseratio criterion after deconvolution,†J. Opt. Soc. Am. A 27, 2123– 2131 (2010).
O. Palillero-Sandoval, J. Félix Aguilar, and L. Berriel-Valdos, â€Phase mask coded with the superposition of four Zernike polynomials for extending the depth of field in an imaging system,†Appl. Optics 53, 4033–4038 (2014).
R. N. Zahreddine, and C. J. Cogswell, â€Binary phase modulated partitioned pupils for extended depth of field,†in Proceedings to Imaging and Applied Optics 2015, IT4A.2 (Optical Society of America, Arlington, 2015).
V. Le, Z. Fan, and Q. Duong, â€To extend the depth of field by using the asymmetrical phase mask and its conjugation phase mask in wavefront coding imaging systems,†Appl. Optics 54, 3630–3634 (2015).
L. Liu, F. Diaz, L. Wang, B. Loiseaux, J. Huignard, C. Sheppard, and N. Chen, â€Superresolution along extended depth of focus with binary-phase filters for the Gaussian beam,†J. Opt. Soc. Am. A 25, 2095–2101 (2008).
M. Demenikov, E. Findlay, and A. Harvey, â€Miniaturization of zoom lenses with a single moving element,†Opt. Express 17, 6118–6127 (2009).
G. Muyo, A. Singh, M. Andersson, D. Huckridge, A. Wood, and A. Harvey, â€Infrared imaging with a wavefront-coded singlet lens,†Opt. Express 17, 21118–21123 (2009).
X. Guo, L. Dong, Y. Zhao, W. Jia, L. Kong, Y. Wu, and B. Li, â€Imaging and image restoration of an on-axis three-mirror Cassegrain system with wavefront coding technology,†Appl. Optics 54, 2798–2805 (2015).
F. Diaz, M. Lee, X. Rejeaunier, G. Lehoucq, F. Goudail, B. Loiseaux, S. Bansropun, et al., â€Real-time increase in depth of field of an uncooled thermal camera using several phase-mask technologies,†Opt. Lett. 36, 418–420 (2011).
T. Zhao, T. Mauger, and G. Li, â€Optimization of wavefront-coded infinity-corrected microscope systems with extended depth of field,†Biomed. Opt. Express 4, 1464–1471 (2013).
R. Zahreddine, and C. Cogswell, â€Total variation regularized deconvolution for extended depth of field microscopy,†Appl. Optics 54, 2244–2254 (2015).
Y. Q. He, J. Q. Li, J. Pan, and Y. J. Li, â€Optimization of phase mask based iris imaging system through the optical characteristics,†Proc. SPIE 8711 , 871107 (2013).