1 Radiation Detection Technique using Smartphones 1.1 Introduction 1.2 Raydose-V1 App 1.2.1 Real-time Processing Algorithm 1.2.2 Dose Calibration Experiments 1.2.3 Performance Experiments 1.2.4 Results 1.2.5 Discussions 1.3 Raydose-V2 1.3.1 Image Processing Algorithms 1.3.2 Experiments 1.3.3 Result and Discussion 1.3.4 Summary References 2 Radiation Detection Techniques using Surveillance Cameras 2.1 Introduction 2.2 Experiments 2.3 Algorithm 2.3.1 Moving-object Detection and Removal 2.3.2 Grayscale Processing and Gaussian Convolution 2.3.3 Inter-Frame Difference 2.3.4 Image Morphology Processing 2.3.5 Radiation-Information Extraction 2.4 Results 2.5 Discussion 2.6 Summary References 3 A High Sensitivity NaI(TI) Spectrometry 3.1 Introduction 3.2 System Description 3.3 Experiments 3.4 Data Processing and Analysis 3.5 Results 3.5.1 Energy Shift of the Electronics 3.5.2 Average Pulse Waveforms 3.5.3 Energies of APWs 3.5.4 Energy Spectra 3.5.5 Energy Resolutions 3.6 Discussion and Conclusion References 4 Radiation Location and Imaging using Scintillator Detectors 4.1 System 1 : An Attenuation based Sandwich Detector 4.1.1 Detector Scheme 4.1.2 Mathematical Model 4.1.3 Virtual Case Study 4.1.4 Experimental Results 4.1.5 Error Analysis 4.1.6 Summary 4.2 System 2: A 360 Degree Sensitive Detector 4.2.1 Description of the Design 4.2.2 Source Locating Algorithm 4.2.3 Verified Experiments 4.2.4 Experimental Results 4.2.5 Summary 4.3 System 3: A Direction-Sensitive Spherical Detector with 4π View 4.3.1 Description of the Design 4.3.2 System Components 4.4 System 4: A Coded-Aperture Camera for Radiation Imaging 4.4.1 Introduction 4.4.2 The MURA Mask 4.4.3 Scintillator Detector 4.4.4 Image Reconstruction 4.4.5 Radiation Imaging Studies 4.4.6 Image Registration 4.4.7 Summary References 5 Nuclear Medical Imaging System 5.1 Introduction 5.1.1 Medical Imaging Technology 5.1.2 Molecular Imaging 5.1.3 Small Animal Imaging 5.2 SPECT Imaging 5.3 PET and PET/CT Imaging 5.4 A Compact Animal PET/SPECT/CT System 5.4.1 System Setup 5.4.2 Performance Evaluation 5.4.3 Results 5.4.4 Discussion and Conclusion References 6 Intrinsic Radiation of Lutetium Based PET Detector 6.1 Introduction of Lutetium-176 6.2 The Drawbacks of IRL in PET 6.2.1 Common PET Imaging 6.2.2 Low Activity PET Imaging 6.2.3 Long Axial FOV PET 6.2.4 PET/SPECT Imaging 6.3 The Traditional Benefits of IRL in PET Systems 6.3.1 For Detector Study 6.3.2 For Monitoring PET Channel Gain Drift 6.3.3 For Time Alignment of TOF-PET 6.3.4 For Generating Transmission Image 6.4 For Pinhole Geometry Calibration 6.4.1 Lu-176 Based Calibration Method 6.4.2 Simulation Studies and Results 6.4.3 Experiment Studies and Results 6.5 For PET/CT Alignment 6.5.1 Introduction of PET/CT Alignment Calibration 6.5.2 Materials and Experiments 6.5.3 Transformation Matrix Generation Algorithm 6.5.4 Results 6.5.5 Discussions 6.5.6 Summary 6.6 Conclusions References 7 High Performance Position Sensitive Scintillator Detectors for PET 7.1 Components of Detectors 7.1.1 Seintination Crystal Selection 7.1.2 Photodetector Selection 7.1.3 ASIC Chip 7.2 Experiment Platform 7.3 Detector Modules 7.3.1 8×8 Array Detector Module 7.3.2 12×12 Array Detector Module 7.3.3 16×16 Array Detector Module 7.3.4 22×22 Array Detector Module 7.4 PET Detectors with Air-gapped Pixelated LYSO 7.4.1 Single Crystal Experiment 7.4.2 8×8 LYSO Module Experi