Patent ID: 7217928

Claim:
A detector assembly for improved depth of interaction determinations comprising: a scintillator crystal for interacting with a photon from a photon source and creating a plurality of optical signals, said interaction occurring at an interaction site within said scintillator crystal and being characterized by an x-position, a y-position and a z-position, said scintillator crystal having a first end and a second end; at least one first transducer for receiving one of the plurality of optical signals from said scintillator crystal and converting the one of the plurality of optical signals to a first electrical signal, said first transducer having a first active area for receiving optical signals, and said first active area of said first transducer being optically coupled to the first end of said scintillator crystal; a second transducer for receiving another of the plurality of optical signals from said scintillator crystal and converting the another of the plurality optical signals to a second electrical signal, said second transducer positioned closer to the photon source than the at least one first transducer and having a second active area for receiving optical signals and said second active area of said second transducer being optically aligned for receiving optical signals from a second end of said scintillator crystal; an optical guide, said optical guide optically coupled between said second end of said scintillator crystal and said active area of said second transducer, said optical guide being conducive to direct optical signals to said active area of said second transducer; and a computer array electrically coupled to said at least one first transducer to receive said first electrical signal for generating a centriod for determining the x-position and the y-position of the interaction site, and to said second transducer for receiving said second electrical signal for determining said z-position from said second electrical signal, wherein said at least one first transducer and the second transducer have a M:1 correspondence, where M is equal to one or more.