Indian Journal of Science and Technology

Abstract

The performance of a diagnostic Digital Radiography (DR) system has been improved. In this study, we determined the appropriate inspection distance that can reduce geometric light sharpness and radiation dose. Phantom images were acquired by creating phantom at size of 14.4 mm × 14.4 mm × 1.5 mm while changing the Objectto Image Receptor Distance (OID) and Source to Image Receptor Distance (SID). To acquired phantom images, OID was changed from 5 cm interval to 0 ~ 30 cm and SID was changed from 10 cm interval to 100 ~ 150 cm. The length was measured by Image J program. We used a small focus and experimented this study in tube voltage 40 kVp, tube current capacity 2 mAs. Our results revealed that the enlargement ratio of phantom image was gradually reduced when SID was increased. However, the enlargement ratio was increased when OID was increased. OID distance was the factor that had the most impact on image enlargement in general medical examination using X-ray. It is difficult to control OID in medical image intended for human body. However, SID can be controlled. Therefore, image magnification could be reduced by increasing SID. Reasonable SID was 130 cm in general diagnostic radiology test using a diagnostic DR system.
Keywords: DR (Digital Radiography) System, Image J, Magnification Rate, OID (Object to Image Receptor Distance), SID (Source to Image Receptor Distance)