先進(jìn)PET電子學(xué)系統(tǒng)的開發(fā)和研制課件

1、2015新一代輻射探測(cè)技術(shù)與公眾安全高峰論壇報(bào)告2015年7月11日先進(jìn)PET電子學(xué)系統(tǒng)的開發(fā)和研制PET system introductionDetectorScintillatorPhoton sensorData acquisition electronicsDetector readoutCoincidence Imaging process and reconstructionAdvanced PET technologyPET imaging system performance Goal:High ResolutionHigh SensitivityDetector techn

2、ology:Silicon based photon sensor (SiPM)Depth of Interaction (DOI) measurementData acquisition electronicsTime-of-flight measurementHigh counting rate and high channel number support System design:Multi-modality system support: PET/MR, PET/CT, PET/MR/CTSiPM photon sensorMR compatible!DOI measurement

3、 DOI measurement in detector: reduce parallel error for LOREspecially useful for small system or compact system desginWith DOI Without DOI DOI measureable detector designTime of fight measurement Time of Fight measurement can improve PET imaging performance Sub-nano second timing resolution is neede

4、d for practical ToF application Large size SIPM based detector designCrystal pixel size: 2 x 2 x 30 mm3Overall detector size: 65 x 65 x 40 mm3Crystal number: 32 x 32 = 1024SiPM: Hamamatsu MPPC array 5 x 5 x 2 = 50Total SiPM readout channels: 20 x 20 x 2 = 800Challenging for front-end readoutHigh res

5、olution more pixel readoutDOI readout readout channel number doublesHigh sensitivity high counting rateCompact size low power consumption and small form factor Summary of design target: High readout channel number with high counting rate capability in small sizeImpossible? Channel reduction technolo

6、gy: signal multiplexingSpecial ASIC readout chip design signal multiplexingChange individual readout into X and Y readout Reduce SiPM readout channels: from 800 to 80 SiPM readout ASICDevelopment codeTIMPIC IIInput channel number16Power consumption10mW/chInput signal range10pC 1000pCIntrinsic timing

7、 resolution20-30ps FWHMCMOS technology0.35umPackageBGA 121 pinsFront-end readout electronicsNO ADCs neededFPGA directly process the output of ASICAll analog signal converted in front-endOutput to LVDS cable 64 channels for each front-end readout boardCounting rate: up to 1M/sCompare with traditional

8、 PET data acquisition systemTraditional CFD, ADCand TDC basedPure digital ASIC and FPGA basedDetector module performance Detector module performance 17%18%28%DOI resolution is about 4mmData acquisition electronics designLVDS data transfer rate: 1.0 Gb/sOverall front-end data transfer rate: up to 48G

9、b/sMaximum input channel number: 3072Maximum front-end counting rate 48M/sMaximum coincidence event rate: 12.5M/sSystem timing resolution: 0.3ns bin size with 0.6ns FWHM (ToF)Data acquisition electronics systemPrototype PET system 1Rotating PET systemFOV size about 57 mmFor small animal PET imagingS

10、ystem built in 2012Prototype PET system 2Square shape PET systemFOV size about 79 mmFor small animal PET imagingSystem built in 2014 Imaging results phantomSystem resolution: 1.5mmDOI is very important in high resolution compact systemWith DOI Without DOI Imaging results - mouseBRAIN/breast PET syst

11、em Square shape PET systemFOV size about 320 mmFor Brain/Breast PET imagingSystem is projected to be built in 2015 Proton therapy applicationPET system is used to do proton beam range verification in proton therapysummaryPET development trends: SiPM photon sensorDOI measureable ToF measureableMulti-modality Imaging system (PET/CT, PET/MR) supportAdvanced electronics des