Kotoku Jun'ichi, Makishima Kazuo, Okada Yuu, Negoro Hitoshi, Terada Yukikatsu, Kaneda Hidehiro, Oda Minoru
Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
Appl Opt. 2003 Jul 10;42(20):4176-85. doi: 10.1364/ao.42.004176.
An improvement of Fourier synthesis optics for hard x-ray imaging is described, and the basic performance of the new optics is confirmed through numerical simulations. The original concept of the Fourier synthesis imager utilizes nonposition-sensitive hard x-ray detectors coupled to individual bigrid modulation collimators. The improved concept employs a one-dimensional position-sensitive detector (such as a CdTe strip detector) instead of the second grid layer of each bigrid modulation collimator. This improves the imaging performance in several respects over the original design. One performance improvement is a two-fold increase in the average transmission, from 1/4 to 1/2. The second merit is that both the sine and cosine components can be derived from a single grid-detector module, and hence the number of imaging modules can be halved. Furthermore, it provides information along the depth direction simultaneously. This in turn enables a three-dimensional imaging hard x-ray microscope for medical diagnostics, incorporating radioactive tracers. A conceptual design of such a microscope is presented, designed to provide a field of view of 4 mm and a spatial resolution of 400 microm.
描述了一种用于硬X射线成像的傅里叶合成光学器件的改进，并通过数值模拟证实了新光学器件的基本性能。傅里叶合成成像仪的原始概念利用与单个双栅调制准直器耦合的非位置敏感硬X射线探测器。改进后的概念采用一维位置敏感探测器（如碲化镉条状探测器）代替每个双栅调制准直器的第二栅层。这在几个方面比原始设计提高了成像性能。一项性能改进是平均透射率提高了两倍，从1/4提高到1/2。第二个优点是正弦和余弦分量都可以从单个栅极-探测器模块中得出，因此成像模块的数量可以减半。此外，它还能同时提供沿深度方向的信息。这反过来又使得一种用于医学诊断的三维成像硬X射线显微镜成为可能，该显微镜结合了放射性示踪剂。展示了这种显微镜的概念设计，旨在提供4毫米的视场和400微米的空间分辨率。
