Determination of half value layers of X-ray equipment using computed radiography imaging plates Eiji Ariga, Shigeki Ito, Shizuhiko Deji, Takuya Saze, Kunihide Nishizawa Physica Medica: European Journal of Medical Physics Volume 28, Issue 1, Pages 71-75 (January 2012) DOI: 10.1016/j.ejmp.2011.01.001 Copyright © 2011 Associazione Italiana di Fisica Medica Terms and Conditions
Figure 1 Layout of air kerma measurement. (a) Ionization chamber, and (b) IP. Physica Medica: European Journal of Medical Physics 2012 28, 71-75DOI: (10.1016/j.ejmp.2011.01.001) Copyright © 2011 Associazione Italiana di Fisica Medica Terms and Conditions
Figure 2 Dependency of coefficient ‘a’ on absorber thicknesses and tube voltage when coefficient ‘b’ is 0.991. Physica Medica: European Journal of Medical Physics 2012 28, 71-75DOI: (10.1016/j.ejmp.2011.01.001) Copyright © 2011 Associazione Italiana di Fisica Medica Terms and Conditions
Figure 3 Transmission curves of air kermas obtained with ionization chamber and IP. Air kerma values were measured with an ionization chamber, and calculated with the modified Eq. (2). Tube voltage: 80kV, Additional filtration: 0mm Al. Physica Medica: European Journal of Medical Physics 2012 28, 71-75DOI: (10.1016/j.ejmp.2011.01.001) Copyright © 2011 Associazione Italiana di Fisica Medica Terms and Conditions
Figure 4 Relative transmission curves obtained by normalizing the transmission curves in Fig. 3 to the 0 absorber thickness. Physica Medica: European Journal of Medical Physics 2012 28, 71-75DOI: (10.1016/j.ejmp.2011.01.001) Copyright © 2011 Associazione Italiana di Fisica Medica Terms and Conditions
Figure 5 Comparison between HVLch and HVLIP. HVLch, HVL determined with the ionization chamber; HVLIP, HVL determined with IP using the modified equation. Ideal line, A line where HVLIP completely coincides with HVLch. HVLch and HVLIP were determined for 64 combinations of 8 tube voltages of 50, 60, 70, 80, 90, 100, 110, and 120kV, and 8 additional filtrations of 0, 0.2, 0.4, 0.6, 1.0, 1.5, 2.0, and 2.5mm Al. Physica Medica: European Journal of Medical Physics 2012 28, 71-75DOI: (10.1016/j.ejmp.2011.01.001) Copyright © 2011 Associazione Italiana di Fisica Medica Terms and Conditions
Figure 6 Relative discrepancies between HVLch and HVLIP. HVLch, HVL determined with the ionization chamber. HVLIP, HVL determined with IP using the modified equation. Relative discrepancies were determined for 64 combinations of 8 tube voltages of 50, 60, 70, 80, 90, 100, 110 and 120kV, and 8 additional filtrations of 0, 0.2, 0.4, 0.6, 1.0, 1.5, 2.0, and 2.5mm Al. Physica Medica: European Journal of Medical Physics 2012 28, 71-75DOI: (10.1016/j.ejmp.2011.01.001) Copyright © 2011 Associazione Italiana di Fisica Medica Terms and Conditions