Evaluation of a novel CCD camera for dose reduction in digital radiography

Work is currently underway to investigate the application of a novel, low light level charge-coupled device to the field of digital radiography. The CCD has been developed by Marconi Applied Technologies. The image sensor in the camera is a frame transfer device with an image size of 576/spl times/288 pixels and a pixel size of 20/spl times/30 /spl mu/m/sup 2/. The readout is standard 625-line video producing 25 frames per second at a pixel read out rate of 11.109 MHz. Images are captured using a digital image acquisition card. The CCD has increased sensitivity at low light levels and is able to operate at high levels of gain with the advantage of lower levels of noise in comparison with standard CCDs. For radiographic purposes a system based upon this device has the potential to operate at reduced irradiation levels. The overall aim of this work is to investigate dose savings in the field of fluoroscopy that may be achieved with this device. This paper presents an evaluation of the noise performance of the CCD. Some preliminary work to estimate dose levels in a simple CCD based imaging system is discussed.