Tomographic Implementation of Astronomical Speckle Imaging from Bispectra

作者：Kuwamura Susumu^*; Yoshinoya Yuuki; Miura Noriaki; Tsumuraya Fumiaki; Sakamoto Makoto; Baba Naoshi

来源：Optical Review, 2011, 18(1): 19-26.

DOI：10.1007/s10043-011-0023-1

• astronomical speckle imaging
• bispectrum
• block-building method
• projection
• tomographic reconstruction

A bispectral method for astronomical speckle imaging utilizes an average speckle bispectrum of an object to derive its Fourier phase. There has been, however, a problem in conventional bispectral algorithm owing to difficulty in processing bispectral data in a four-dimensional (4D) space. In this paper, we propose an implementation to overcome this problem, where a one-dimensional (1D) object projection is reconstructed from a two-dimensional (2D) average bispectrum of speckle projections, and object projections so obtained at various angles are then tomographically combined into a 2D object image. In this tomographic approach, processes are separable into those for individual projection angles, implying that bispectral data required to be stored at a time are from 4D to 2D and computation time can be substantially reduced by parallelizing angle-by-angle processes. We have performed experiments using simulated and observed data, and have demonstrated the feasibility of the present approach with an achievable accuracy comparable to that of a conventional approach.

• 出版日期2011-1