Image plate can be used as a two-dimension positioncasensitive detector forpositrons. In the sodium-22 source experiment

a linear relation between the positronfluence f(e+ ) and output signal intensity f(p) was obtained

written as f(p)=bf (e+ )

b= 1.38×10-5. Since the pixel size of the image plate was 25 μ m × 25 μm forthe analyzer

we used it on our slow positron beam line and gained a meaningfulpicture

the slow positron beam spot and corresponding intensity could be shown atthe same timc. This two dimensional positiontalsensitive detector is a extremelyuseful tool for detecting slow positron.