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Fast and Robust Reconstruction of Penumbral Images by Combining Multiple Wiener Filters

Shinya NOZAKI, Rumiko AZUMA, Shinsuke FUJIOKA¹⁾, Yen-wei CHEN²⁾ and Yoshinori NAMIHIRA³⁾

Transdisciplinary Research Organization for Subtropics and Island Studies, University of the Ryukyus, Okinawa 903-0213, Japan

1)

Institute of Laser Engineering, Osaka University, Osaka 565-0871, Japan

2)

College of Information Science and Engineering, Ritsumeikan University, Shiga 525-8577, Japan

3)

Faculty of Engineering, University of the Ryukyus, Okinawa 903-0213, Japan

(Received 7 December 2010 / Accepted 5 April 2011 / Published 1 July 2011)

Abstract

Penumbral imaging is a powerful technique for imaging with penetrating radiation such as neutrons and hard x rays. The reconstructed image can be obtained by the deconvolution of the detected image. Usually a Wiener filter is used for the reconstruction. The limitation of the Wiener filter is that it will introduce a significant distortion when the detected image contains noise. On the other hand, heuristic methods can obtain clear reconstructed image from noisy penumbral images. However, it significantly takes computation time. We proposed a new reconstruction method in the penumbral imaging to obtain clear reconstructed image by combining the multiple Wiener filters and the method can reduce computation time. The effectiveness of the proposed method has been demonstrated by computer simulation and real laser plasma experiment.

Copyright (c) 2011 The Japan Society of Plasma Science and Nuclear Fusion Research

Keywords

penumbral imaging, deconvolution, Wiener filter, heuristic method, computation time

DOI: 10.1585/pfr.6.2406071

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References

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This paper may be cited as follows:

Shinya NOZAKI, Rumiko AZUMA, Shinsuke FUJIOKA, Yen-wei CHEN and Yoshinori NAMIHIRA, Plasma Fusion Res. 6, 2406071 (2011).