Light Sharing
Light Sharing Specifications
The decoding capability of a detector block depends on light yield of the crystal, light collection efficiency and PMT photocathode characteristics. Higher light output of the crystal and higher quantum efficiency of the PMT could greatly improve the decoding capability of the detector.
Comparing to conventional detector design, our PQS detector has higher light collection efficiency mainly because of not using light guide between detector blocks and PMTs and using reflector patterns between crystals. In our PQS block detector, the crystals and the reflector patterns that are placed on the crystal interfaces play the role of an internal light guide for distributing scintillation light into the four PMT’s. The reflector patterns in crystal gaps are optimized by simulation and experimental study. The reflectors patterns, are made up of 3M Vikuiti™ ESR (enhanced spectral reflector) film. In addition, in order to optimize the crystal decoding capability, a specific crystal surface finishing is used.
Crystal Surface Finishing
A Comparison between the 2-D maps of LYSO 14 × 14 1Detector Blocks ( 19-mm PMT) with different crystal surface finishing.
Reflective Patterns
Light-Sharing Simulator
Comparison of the 2-D Crystal Decoding Map of a 10 × 10 BGO Block
The crystal decoding map obtained (left) with light-sharing simulator and (right) experimentally.