Background: Developing a style of special imaging device

such as positron emission mammography

is very important for early-stage breast cancer detection and cure. Purpose: The aim is to design planar detectors for positron emission mammography. Methods: The detector was segmented into a pixilated array consisting of 22×74elements. Its crystal pitch and crystal cross section are 2 mm and 1.88 mm×1.88 mm

respectively. The effective area is 44 mm×148.56 mm. The array is coupled to 3 Hamamatsu H8500 position sensitive photomultiplier tubes in neck and neck way. Results: For left detector head

its energy resolution ranged from 10.54% to 19.84% full width of maximum(FWHM)

with a mean of 13.34%. For right head

its energy resolution ranged from 11.75% to 33.72%FWHM

with a mean of 14.17%. Coincidence timing resolution for the detector pair is measured to be 2.6 ns FWHM.Effective prompt event rate is 21×103s 1. The image spatial resolutions in X and Y direction are 1.14 mm and 1.20 mm

respectively. Conclusion: The results show that the planar detectors of positron emission mammography are suitable for detecting early-stage breast cancer.