Browsing Theses by Supervisor "Karim, Karim"
Now showing items 1-11 of 11
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Design and Optimization of a Stacked Three-Layer X-ray Detector for Multi-Spectral Medical Imaging Applications
(University of Waterloo, 2016-06-16)Dual-Energy (DE) imaging is a powerful technique in x-ray imaging that increases the ability to detect specific materials in a cluttered background, and is used to more accurately visualize anatomical features and diagnose ... -
Design, Fabrication and Characterization of a Unipolar Charge Sensing Amorphous Selenium X-ray Detector
(University of Waterloo, 2023-06-19)Amorphous Selenium is a direct conversion photoconductor that has been widely used in X-ray imaging applications. Due to its high spatial resolution A-Se plays an important role in breast cancer screening and diagnostics, ... -
Device Architectures for Improved Temporal Response with Amorphous Selenium Radiation Detectors
(University of Waterloo, 2019-07-29)Amorphous selenium (a-Se) is a commercially mature direct conversion photoconductor capable of very high spatial resolution that enables the early detection of small and subtle lesions in breast cancer screening and ... -
A High-Resolution Direct-Conversion CMOS X-Ray Imager with Code-Division-Multiplexed Readout
(University of Waterloo, 2023-04-21)This thesis presents the design and characterization of a high-spatial-resolution direct-conversion X-ray imager built using complementary metal-oxide-semiconductor (CMOS) technology integrated with an amorphous-selenium ... -
Hybrid Amorphous Selenium-CMOS Photon-Counting X-ray Imager
(University of Waterloo, 2018-05-23)Many medical imaging modalities, such as mammography and micro-computed tomography, utilize digital X-ray imagers to observe human anatomy. Direct digital X-ray imagers rely on a sensor layer (typically a photoconductor) ... -
Hybrid Amorphous-Selenium/CMOS Low-Light Imager
(University of Waterloo, 2018-07-18)This thesis aims to demonstrate a low-light imager capable of moonlight-level imag- ing by combining a custom-designed complementary-metal-oxide-semiconductor (CMOS) pixel array with amorphous selenium (a-Se) as its ... -
Hybrid Semiconductor Detectors for High Spatial Resolution Phase-contrast X-ray Imaging
(University of Waterloo, 2019-02-20)When conventional x-ray radiography presents inadequate absorption-contrast, higher sensitivity can be achieved using phase-contrast methods. The implementation of phase-contrast x-ray imaging using propagation-based ... -
Noise Characterization of a CMOS X-Ray Image Sensor
(University of Waterloo, 2018-09-05)The objective of this thesis is to validate the noise performance of a high resolution CMOS X-ray imager. We carry out a detailed noise analysis on a four-quadrant CMOS imager and the external hardware. Careful analysis ... -
Novel photo-detector architectures for high-energy radiation imaging applications
(University of Waterloo, 2023-10-18)This work is an investigation of amorphous Selenium (a-Se) based semiconductor detectors for high-energy radiation imaging applications. The work focuses on enhancing the detection efficiency of a-Se while maintaining ... -
Phase Retrieval Methods for Polychromatic Propagation-Based Phase-Contrast X-ray Imaging
(University of Waterloo, 2019-07-18)X-ray imaging, based on conventional attenuation methods, is employed in various industrial, medical and scientific imaging application. Phase-contrast X-ray imaging is an emerging modality that has shown promise to image ... -
Sensors for Wireless Body Monitoring Applications
(University of Waterloo, 2017-12-19)Body monitoring systems have recently drawn great attention to modern electronic consumers due to their various health−care and security applications. However, most of the existing monitoring systems need wire connections ...