Luximos: A 768x64 900-fs Tileable Pipelined X-ray CMOS Image ray CMOS Image Sensor for Dental Imaging with 2.6 LSB/nGy Sensitivity

In this paper a stitched array of 768x64 pixels for X-ray dental imaging is presented. The sensor architecture allows to increase the frame rate up to 900 fps thanks to a pipeline approach that minimizes the deadtime between consecutive frames. A column-based ADC converts pixel values in digital form while an external FPGA performs the operation of TDI accumulation, thus increasing the SNR. Internal programmable gain allows to achieve a maximum sensitivity of 2.6 LSB/nGy and, at the same time, to extend the dynamic range of the sensor in case of high intensity. The final system consists of two sensors each one having a size of 74.5x9 mm, assembled in a PCB and coupled with a high sensitive columnar thallium-doped cesium iodide (CsI(Tl)) scintillator for X-ray conversion. The sensor, fabricated in a standard CMOS 0.15 μm technology with stitching approach, shows a pixel size of 97 μm.