Mirror curves are constructed by bouncing a light ray through a space that contains mirrors off which the ball bounces. In a rectangular space, if the mirrors are placed symmetrically under one of the 2D symmetry groups (or “wallpaper groups”), then the resulting path has the same symmetry group. Inspired by certain sona designs of the Cokwe people of Africa, we search for single-component mirr...

3次元空間の視覚情報を, 個別の入出力方式(多眼, ホ ログラフィなど)に依存しない中立的な形 で記述する ためには, 光線情報による記述が有効である . 3次元 空間中の光線は, 位置 (X,Y, Z)における伝搬方向 (θ, φ) をパラメータとして5次元の情報空間 f(X,Y, Z, θ, φ)の 中に記述される . この光線情報による空間記述に よって, 3次元画像の処理や符号化を「光線群の記述, 処 理, 符号化」として統一的に論ずることが可能となる. 最 近では, CGの分野においても, 同様の考え方が注目を集 めている . しかし3次元空間における光線の情報量は膨大であり, 適切な光線情報をいかに効率的に取得するかが問題とな る. 本研究速報では, 情報空間 f(X,Y, Z, θ, φ)に対して サンプリングと補間の概念を導入し, 光線情報を効率的 に取得する方式につ...

White-beam x-ray fluorescence holograms were recorded using a 50 watt x-ray tube for a Cu3Au single crystal. Element sensitivity for this model sample was explicitly demonstrated by measuring distinct holograms using Cu K and Au L x-ray fluorescence. The phase sensitivity of the recorded holograms enabled us to obtain projections of the local atomic structure and image the electron density with...

The imaging performance of X-ray optics (expressed in terms of HEW, HalfEnergy-Width) can be severely affected by X-ray scattering caused by the surface roughness of the mirrors. The impact of X-ray scattering has an increasing relevance for increasing photon energy, and can be the dominant problem in a hard X-ray telescope like SIMBOLX. In this work we show how, by means of a novel formalism, ...

Despite the extensive use of polycapillary x-ray optics for focusing and collimating applications, there remains a significant need for characterization of the coherence properties of the output wavefield. In this work, we present the first quantitative computational method for calculation of the spatial coherence effects of polycapillary x-ray optical devices. This method employs the coherent ...

The recent demonstration of a metamaterial phase hologram so thin that it can be classified as an interface in the effective-medium approximation [Science 334, 333 (2011)] has dramatically increased interest in generalized laws of refraction. Based on the fact that scalar wave optics allows only certain light-ray fields, we divide generalized laws of refraction into two categories. When applied...

We demonstrate that the soft X-ray diffraction pattern from a micron-size noncrystalline specimen can be recorded and inverted to form a high-resolution image. The phase problem is overcome by oversampling the diffraction pattern. The image is obtained using an iterative algorithm. The technique provides a method for X-ray microscopy requiring no highresolution X-ray optical elements or detecto...