Use of storage phosphor imaging plates in portal imaging and high-energy radiography: the intensifying effect of metallic screens on the sensitivity.

The sensitivity of storage phosphor imaging plates (SPIP) at megavolt photon energies (60Co, 6-, 10-, and 18-MV radiotherapy beams) is studied both experimentally and by Monte Carlo radiation transport calculations. In addition, the same techniques are used to investigate the intensifying effect of metal screens on the sensitivity of the SPIP. The results provide evidence that the sensitivity of the SPIPs is proportional to the absorbed energy in the phosphor layer per cGy.

Intensifying effect of metallic screens on the sensitivity of x-ray films for 400-kV bremsstrahlung photons.

Measurements are carried out to determine the relative photographic effect produced by electrons emanating from metallic screens on a typical radiographic film. The electrons are produced in metal foils of aluminum, copper, and lead by the interaction of photons in a 400-kV bremsstrahlung beam. Intensification factors of up to 1.