ABSTRACT
Radiography offers insight into the inner structures of materials that may not be visualized under other conditions. It permits a range of noninvasive and nondestructive views of objects that is taken for granted in the modern context. Although radiography imaging is generally associated with x-rays, it should be kept in mind that other types of ionizing radiation may be used. Some isotopes are radioactive and may be referred to as radioisotopes. Radioisotopes are materials that emit radiation into their surroundings due to the unstable atomic nucleus. The x-rays travel in straight lines and are not influenced by any other magnetic or electrical fields. As is well known, x-rays will reveal the inner structures of materials as they penetrate them. Neutron radiography is a specialized technique where high velocity neutrons are used to create the radiograph. Lower energy x-rays are all that is needed to differentiate the features of interest for nearly all document materials.
