Stray light reduction in optical computed tomography using a convergent cone-beam source

8th International Conference on 3D Radiation Dosimetry

Jordan, Kevin^1,2 ; Dekker, Kurtis^1 ; Battista, Jerry^1,2

London Regional Cancer Program, London Health Sciences Centre, London, United Kingdom^1

Department Medical Biophysics, Western University, London

ON, Canada^2

关键词: Fresnel lens;    Image forming;    Imaging efficiency;    Light level;    Optical computed tomography;    Refractive index matching;    Stray light reduction;    Water solutions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/573/1/012033/pdf
DOI  :  10.1088/1742-6596/573/1/012033

来源: IOP

【 摘 要 】

The planar diffuser light source for a cone-beam optical CT scanner was replaced with a filtered LED and large Fresnel lens. The source was focused on a camera and convergent cone-beam images were acquired. Images are sensitive to mismatches in the refractive index of vessels, samples and matching liquid. For PETE jars and water solutions, a loss of approximately 30% of the projections was demonstrated. Teflon PFA cylinders provided better refractive index matching and more accurate reconstructions. The convergent cone-beam source dramatically increased imaging efficiency by a factor of 1000 and reduced stray light levels by confining illumination to image forming rays.