The Design Of PET Detector And Decoding Circuit Based On The Silicon Photomultiplier(SiPM)

PET can evaluate the metabolic and biochemical reactions of various organs dynamically at the cellular and molecular level by using the tracing principle and the positron coincidence detection technique.PET plays an important role in the diagnosis of tumor,nervous system and related pathological studies.Detector and decoding circuit is the front-end electronics system and the core signal detection components of PET equipment.The detector capture 511 KeV gamma photon produced by the annihilation reaction and scintillation crystal change the gamma photon into visible light then the visible light turned into electrical signal by phototube.Through data processing of amplification,integral,summation of signal and AD transform,the location information?energy information and temporal information of annihilation reaction is delivered to PET subsequent processing circuit to rebuild image.Therefore,the detector and decoding circuit optimization design is very important for the PET equipment.The main work of this paper is to develop the detector based on SiPM(Silicon Photomultiplier)and decoding circuit.The first item is to design a photon detector module by using 5x5 SiPM array.SiPM array use DPC method for position decoding,and the actual test results show that the design can improve the spatial resolution of the detector from the existing 1.79 mm to 1.35 mm,and achieve the desired design purpose.The second item is to solve the problem of time resolution degradation in SiPM array structure by using fast diode isolation method.