Dynamic Bowtie Filter for CT

The aim of this project is to build and characterize an active bowtie filter for medical CT. With the investigation in photon counting detectors, dynamic response range becomes a large issue due to crystal material property and electronic counting limitations. To limit the dynamic range a detector encounters, a static 'bowtie' filter can be used to attenuate open space on the sides of the patient to prevent the detector from being swamped by a high count rate. Current bowtie filters are fixed blocks. In this project we seek to develop an adjustable bowtie filter that can dynamically be changed to allow patients of different sizes and shapes to be imaged without mismatch between a stock filter and the patient.