Study of performance of small gamma camera consisting of crystal pixel array and position sensitive photomultiplier tube

摘要

The performance of gamma camera with NaI(Tl) array coupled with position sensitive photomultiplier tube (PSPMT) R2486 has been studied. The pixel size of NaI(Tl) crystal is 2mm x 2mm and the overall dimension of the array is 48.2mm x 48.2mm x 5mm. There are 484 pixels in a 22 x 22 matrix. Because each pixel can produce a much focused light spot and restrict the spread of photons, position resolution of the gamma camera is mainly determined by pixel size. It is shown that crystal array pixel can reduce shrinkage effect and improve intrinsic position resolution greatly via restricting the spread of photons. Experimental results demonstrate that its position resolution and linearity are much improved comparing with the gamma camera using planar crystals coupled with PSPMT.