Design and Construction of an Avalanche Photodioclc-Based Gamma CRmera Prototype

Abstract

<p>Objective: The design of a prototype avalanche photodiode gamma camera and an adaptable and expandable acquisition board. To test the performance of the acquisition board a photomultiplier base camera is constructed and utilized in various configurations. The APD-based gamma camera is tested on the same acquisition board to evaluate its performance.</p> <p>Results:Spectra have been collected and analyzed utilizing four various detector/system configurations. i) a PET module, utilizing a PMT coupled to a pixilated BGO crystal with a high energy Na-22 source. ii) a single PMT extracted from a PET module akin to the one mentioned previously and coupled to NaI(T1) with a Co-57 source. iii) the same PMT coupled to a CsI(T1) crystal with a variety of sources, including Tc-99m, Ga-67 and Co37. iv) an APD coupled to a CsI(T1) crystal with a variety of sources including Tc-99m and Co-57. Images have been collected from multiple camera configurations, all by a 2 by 2 array. APD's with CsI(T!), PMT's and NaI(T1) and a PET module with PMT's on BGO</p> <p>Conclusion: These requirements have been met with the current design and the system has been tested in a controlled environment. collecting spectrum while operating a single channel and for some configurations, images were collected operating a multi-channel array. A number of steps can be taken to improve upon this prototype, The detector itself may benefit from a pixilated crystal and current APD technology. The acquisition board should be transferred to a multiple printed circuit board design allowing it to be implemented ill a black-box manner. Additionally. the current USB bridge' limits the transfer rate of data between the DSC and the' PC. as a result. alternatives should be investigated.</p>