Investigation of Dark-Count-Less Lu₂(SiO₄)O-Multipixel-Photon Detector and Its Application to Photon Counting X-ray Computed Tomography Using Iodine Media

• Eiichi Sato

• Yasuyuki Oda

• Hajime Kodama

• Osahiko Hagiwara

• Hiroshi Matsukiyo

• Akihiro Osawa

• Toshiyuki Enomoto

• Manabu Watanabe

• Shinya Kusachi

• Shigehiro Sato

• Akira Ogawa

Abstract

X-ray photons are detected using a Lu 2 (SiO 4 )O [LSO] single-crystal scintillator with a decay time of 40 ns and a multipixel photon counter (MPPC). The photocurrent from the MPPC is amplified by a high-speed current–voltage amplifier with an 80 MHz-gain-band operational amplifier, and the 200-ns-width event pulses are sent to a multichannel analyzer (MCA) to measure X-ray spectra. The MPPC was driven in the pre-Geiger mode at a bias voltage of 70.7 V and a temperature of 23 °C. Photon-counting computed tomography (PC-CT) is accomplished by repeated linear scans and rotations of an object, and projection curves of the object are obtained by linear scanning at a tube current of 1.5 mA. In PC-CT, the event pulse height is dispersed using a 7-ns-delay comparator. The exposure time for obtaining a tomogram is 10 min with scan steps of 0.5 mm and rotation steps of 1.0°. At a tube voltage of 80 kV, the maximum count rate is 250 kcps. We carry out PC-CT using iodine media and confirm the energy-dispersive effect with changes in the lower level voltage of event pulses using a comparator.

Journal

• Japanese Journal of Applied Physics

  Japanese Journal of Applied Physics 52 (9R), 092401-, 2013-08-19

  IOP Publishing

Keywords

• General Physics and Astronomy
• General Engineering

Details

• CRID: 1360566399841119872
• NII Article ID: 210000142794
• DOI: 10.7567/jjap.52.092401
• ISSN: 13474065
• ISSN: 00214922
• Web Site: https://iopscience.iop.org/article/10.7567/JJAP.52.092401
• Web Site: https://iopscience.iop.org/article/10.7567/JJAP.52.092401/pdf
• Data Source:
  • Crossref
  • CiNii Articles