Depth-of-interaction recognition using optical filters for nuclear medicine imaging

This paper describes a depth-of-interaction recognition method that can be applied to radiation detectors for positron emission tomography. The proposed method uses optical filters to differentiate wavelength distribution of scintillation photons depending on crystal depth positions. Then the crystal of interaction can be identified with a multianode photodetector whose sensitive surface is partly covered with optical filters. A validation experiment was performed with a position sensitive photomultiplier. As a result, it was proved that the crystal depth of interaction was clearly identified for photoabsorption events.