The figure shows the diffraction image near the end facet of the irregularly microstructured elliptic core fiber (IMEF) experimentally observed with a Si-based CCD camera and a 60x objective lens. The contours of airholes are intentionally depicted for easy recognition. The elliptic core is clearly seen and small spots adjacent to the airholes also carry small portions of energy. (a) The near-field pattern and (b), (c) the far-field patterns of the guided modes of the IMEF. The contour of the airholes in (a) is shown for convenience. In (b) and (c), the white arrows indicate the long axis of the elliptic core and the red arrows indicate the E-field directions. For further details, see the paper by Choi et al., pp.