THE IMAGING PERFORMANCE OF A STORAGE PHOSPHOR SYSTEM FOR DENTAL RADIOGRAPHY

Direct digital imaging systems are becoming increasingly common in den tal radiography. The majority of these systems are based on charge cou pled device (CCD) technology. A relatively new system. based on photo- stimulable phosphor luminescence (PSPL), is now commercially available , This system appears to overcome some of the restrictions of CCD syst ems including those associated With the bulky detector, connecting wir e, limited image size and limited exposure latitude. A physical evalua tion of the PSPL system was conducted including measurements of sensit ometric response modulation transfer function (MTF), noise power spect rum (NPS), noise equivalent quanta (NEQ) and detective quantum efficie ncy (DQE). These measurements were compared with results obtained prev iously for Kodak Ektaspeed (E-speed) film. The results of the evaluati on indicate that the PSPL system may be capable of operating at exposu res up to 80% lower than for film with comparable image quality.