Factors affecting the image resolution and detection efficiency of gamma camera

The need for high performance of organ or tissues images pushed many scientists to study the factors affecting the image resolution. Too many factors such as distance, number of counts, and type of collimator were studied in this paper. Count loss depends on the whole energy spectrum; the apparent dead-time depends on the window fraction. Scatter causes narrower of the window fraction then longer dead-time. Resolution is the most talked about digital camera characteristic and is often used to describe image quality. Diverging, converging and pinhole collimators are useful for the change of field view but the image distortion caused by the magnification with depth is a problem.