NOVEL FEATURES IN BLUE PHASE KOSSEL DIAGRAMS

High resolution Kossel diagram images of the blue phases have been fou nd to reveal previously unobserved features, some theoretically predic ted by Belyakov, et al.. These features consist of gaps in the Kossel line intensity at the crossing point of two or more Kossel lines and i nterference fringes in regions of many-wave diffraction. A simple theo ry, side-stepping the need to solve Maxwell's equations, based on the interference of light diffracted from multiple sets of Bragg planes is shown to qualitatively explain the results. Also, these many-wave dif fraction features are shown to allow a solution to the phase problem i n the blue phases. The modelled results are found to be in contradicti on with the double twist model of BPII.