Inventors:
Michael R. Gambini - Wallingford CT
Gary Benenson - Brooklyn NY
Assignee:
Picker Corporation - Cleveland OH
International Classification:
G01T 120
G01T 1208
Abstract:
A two-stage system for enhancing the imaging uniformity of a scintillation camera is disclosed. The camera includes means for detecting radiation events and for producing radiation count signals indicating the location and energy level of individual detected radiation events. The uniformity correction system compensates for imprecision in the camera's indication of both radiation event regional image count density and event energy level. Compensation for energy indication errors is done by a first stage, prior to a second stage correction for residual nonuniformity in regional image count density. The operations of both stages are carried out in real time for each individual radiation count, independently of the production of other counts. The first stage location and stores a representation of the respective peaks of the detected energy pulse height distribution for each of a plurality of regions in the camera's field of view. This regional profile of the camera's energy response characteristic is used to successively realign for each count the pulse height energy window defined by the camera imaging circuitry, to align the window over the respective energy peak for each count as a function of the count's location indication.
