Amplified Pixel Sensor Architectures for Low Dose Computed Tomography using Silicon Thin Film Technology

摘要

Cone beam computed tomography (CBCT) has been recently reported using flat panel imagers (FPI). Here, detector technology capable of high speed imaging, high spatial resolution, large volume coverage, better contrast resolution and, in particular, lowered patient dose is required. Employing active matrix flat panel imagers (AMFPIs) as cone beam CT detectors has been proposed as a solution for improving volume coverage, contrast and resolution; however, clinical evaluations have shown that they suffer from low speed read out. Unlike passive pixel architecture which is currently the state-of-the-art technology for AMFPIs, our preliminary studies have shown that novel amplified pixel sensor (APS) architectures can overcome the low readout speed, and moreover, they provide gain which can be traded for higher frame rate and lower X-ray doses. Although APS architectures can meet the high dynamic range and low noise requirements of CT imaging, linearity and variations between pixel characteristics are major issues. In this study we will investigate novel APS architectures to address these concerns.