Plastic scintillation fiber array coupling CCD for X-ray imaging
and detection
Shibiao Tang
a
, Jiabao Xie
b
, Qingli Ma
b,
*
a
College of Electronic and Information Engineering, Ningbo University of Technology, Ningbo 315016, China
b
Electronics Department, Electronic Engineering Institute, Hefei 230038, China
article info
Article history:
Received 4 May 2007
Received in revised form 10 December 2008
Accepted 31 January 2009
Available online 13 February 2009
Keywords:
X-ray
Plastic scintillation fiber array
CCD camera
abstract
The performance of using plastic scintillation fiber (PSF) array coupled with charge-cou-
pled devices (CCD) for X-ray imaging and detection is described. The method is simple
and low cost. The experimental setup is present and some obtained images are shown.
Modulation Transfer Function (MTF) of the PSF array was also presented and compared
to earlier reports. The results show that the system can be applicable under some environ-
ments to demonstrate the concept of radiation imaging or detection.
Ó 2009 Elsevier Ltd. All rights reserved.
1. Introduction
X-ray imaging has been increasingly used in many
fields such as medicine, biology, security, industrial testing
and evaluations [1–4]. Recently, traditional technique
based on X-ray film processing has been rapidly replaced
by digital imaging techniques which have the advantages
in improving image quality, enhancing capability for imag-
ing processing and analysis, and utilizing internet for im-
age transfer and image management. In a digital imaging
system, the x-ray transmission pattern is sampled in spa-
tial and intensity dimensions by recording transmitted x-
ray intensity over a large array of imaging elements or pix-
els. Currently, most commonly used digital x-ray imaging
detector relies on scintillation technologies which convert
X-ray into visible light through scintillation materials and
then detect the visible light using an imaging device such
as a CCD imager [5–7]. Traditionally, the scintillation mate-
rials often used are crystals, their sizes are chosen based on
the energy of X-ray. There are a dozen or so scintillation
materials currently commercially available for construct-
ing such an x-ray digital detector [3,7]. Most commonly
used include Cadmium Tungstate (CdWO
4
), Cesium Iodide
(CsI), Bismuth Germanate (BGO), etc [8,9]. To increase the
efficiency or the sensitivity, a thicker scintillation material
usually is desired. However, a thicker scintillator would re-
sult in a larger isotropic spreading of light generated in the
scintillation materials, which can reduce the spatial resolu-
tion of the imager. Thus a compromise or a balance be-
tween the spatial resolution and X-ray absorption
efficiency should be considered while designing and con-
structing an X-ray imager. Furthermore, due to high cost
of scintillation materials, it is desirable to find a simpler
and more cost effective approach in constructing x-ray dig-
ital imagers.
Using scintillation optical fiber array coupled with a
CCD can be considered to construct another kind X-ray dig-
ital imager [10]. In such a detector, a portion of light (con-
verted from incoming X-ray within a fiber) is channeled
along the fiber through total internal reflection, and the Ex-
tra Mural Absorber (EMA) would absorb the remainder
[11,12]. The scattered radiation in a fiber causes a uniform
background. Such a design, in principle, does not require
0263-2241/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved.
doi:10.1016/j.measurement.2009.01.019
* Corresponding author.
E-mail address: qinglima@gmail.com (Q. Ma).
Measurement 42 (2009) 933–936
Contents lists available at ScienceDirect
Measurement
journal homepage: www.elsevier.com/locate/measurement