Multiple slot array collimator to minimize stray light in optical cone beam CT

Abstract

Acceptance of stray light in transmission images is a general imaging problem. A commercial optical cone beam CT scanner, Vista10 was modified to reduce stray light. Further stray light reduction was accomplished by placing vertical slot aperture arrays between the object and the diffusive light source. Comparisons of single and seven aperture arrays demonstrated that transmissions equivalent to scatter free conditions can be achieved with a multiple array collimator. Results for uniform liquids and finger gel phantoms demonstrate that small objects in a bright background are a more stringent test of stray light rejection.