title: High-resolution x-ray imaging using a structured scintillator.
abstract: OBJECTIVE
  In this study, the authors introduce a new generation of finely structured scintillators with a very high spatial resolution (a few micrometers) compared to conventional scintillators, yet maintaining a thick absorbing layer for improved detectivity.
  
  
  METHODS
  Their concept is based on a 2D array of high aspect ratio pores which are fabricated by ICP etching, with spacings (pitches) of a few micrometers, on silicon and oxidation of the pore walls. The pores were subsequently filled by melting of powdered CsI(Tl), as the scintillating agent. In order to couple the secondary emitted photons of the back of the scintillator array to a CCD device, having a larger pixel size than the pore pitch, an open optical microscope with adjustable magnification was designed and implemented. By imaging a sharp edge, the authors were able to calculate the modulation transfer function (MTF) of this finely structured scintillator.
  
  
  RESULTS
  The x-ray images of individually resolved pores suggest that they have been almost uniformly filled, and the MTF measurements show the feasibility of a few microns spatial resolution imaging, as set by the scintillator pore size. Compared to existing techniques utilizing CsI needles as a structured scintillator, their results imply an almost sevenfold improvement in resolution. Finally, high resolution images, taken by their detector, are presented.
  
  
  CONCLUSIONS
  The presented work successfully shows the functionality of their detector concept for high resolution imaging and further fabrication developments are most likely to result in higher quantum efficiencies.
authors: Materials and Nano Physics, School of Information and Communication Technology, KTH Royal Institute of Technology, Electrum 229, Kista, Stockholm SE-16440, Sweden.
authors: Yashar
authors: Y
authors: Hormozan
authors: Materials and Nano Physics, School of Information and Communication Technology, KTH Royal Institute of Technology, Electrum 229, Kista, Stockholm SE-16440, Sweden.
authors: Ilya
authors: I
authors: Sychugov
authors: Materials and Nano Physics, School of Information and Communication Technology, KTH Royal Institute of Technology, Electrum 229, Kista, Stockholm SE-16440, Sweden.
authors: Jan
authors: J
authors: Linnros
mesh_terms: D005240:Feasibility Studies; D016062:Porosity; D012588:Scintillation Counting / Q000295:instrumentation*; D059629:Signal-To-Noise Ratio; D012822:Silicon Dioxide; D014965:X-Rays
chemical_list: D012822:Silicon Dioxide