Phosphor-covered junction CCD x-ray sensor for dental imaging

摘要

Abstract: X-ray imaging devices for dental applications must have an image area of at least 3 $MUL 4 cm$+2$/. MOS CCDs cover an area of about only 1.5 $MUL 2.5 cm$+2$/, in this case the x-ray image should be reduced to these smaller dimensions. This can be realized by tapered optical fibers after the x-radiation has been converted into light. This procedure results in a rather bulky construction. Junction CCDs can be realized in the desired image area of 3 $MUL 4 cm$+2$/, thus making the taper construction unnecessary. Experiments on a linear array Junction CCD covered with a phosphorescent layer have been carried out. These experiments show, that only 3.2 mR for one exposure is needed. This results in a very low radiation load for the patient. The radiation load for the sensor itself is very low too, which makes a high number of exposure possible during the lifetime of the device.!4