PET Detector Light Guide Sheets Reduce Silicon Photomultiplier Count
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Solution Overview
Problem
The existing PET detectors require a large number of silicon photomultiplier tubes, leading to a significant increase in circuit scale and equipment costs, while also posing challenges in reducing the number of signal channels and controlling the circuit scale effectively.
Innovation Solution
The proposed PET detector design reduces the number of silicon photomultiplier tubes by replacing some with high-reflectivity material blocks and using a layer of light guide sheets between the scintillation crystal array units and the silicon photomultiplier tube array units, which assists in light collection and ensures that fluorescence is effectively captured by other silicon photomultiplier tube arrays.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a large number of silicon photomultiplier tubes are used to ensure detection coverage and signal collection, then detection quality is maintained, but circuit scale and equipment costs increase significantly
Solution Approach 1:
The patent introduces light guide sheets as an intermediary component between the scintillation crystals and silicon photomultiplier tubes. These light guides redirect and concentrate scintillation light toward the photodetectors, improving light collection efficiency and enabling reduced photodetector density while maintaining detection quality. This mediator approach resolves the contradiction by decoupling the direct one-to-one mapping between crystals and photodetectors.
Solution Approach 2:
The patent implements position-dependent photodetector arrangement where silicon photomultiplier tubes are strategically positioned based on local light collection requirements. Rather than uniform distribution, the system uses varying densities and positions of photodetectors optimized for specific regions, allowing reduced overall quantity while maintaining local detection quality where most needed.
2Measurement precision
If more silicon photomultiplier tubes are deployed to improve signal collection, then detection precision is enhanced, but equipment costs increase
Solution Approach 1:
Light guide sheets serve as optical mediators that concentrate and redirect scintillation photons toward silicon photomultiplier tubes, enhancing the signal collection efficiency of each individual photodetector. This improves measurement precision by ensuring more photons reach each detector, allowing fewer photomultiplier tubes to achieve the same overall detection precision.
Solution Approach 2:
The patent replaces direct mechanical/optical coupling between each crystal and photodetector with an optical guiding system. Instead of requiring adjacent or directly coupled photodetectors for each crystal, the light guide sheets create an optical field that distributes and concentrates light as needed, substituting physical proximity requirements with optical field management.
3Reliability
If silicon photomultiplier tube density is increased to reduce signal channels, then signal collection improves, but circuit scale expands
Solution Approach 1:
The light guide sheets act as optical intermediaries that consolidate and direct light from multiple crystal regions toward fewer photodetector channels. This optical consolidation allows reduced signal channel count while maintaining signal collection reliability, as the light guides ensure adequate photon delivery to each reduced channel.
Solution Approach 2:
Each silicon photomultiplier tube in the optimized configuration serves multiple functional roles by receiving light from multiple crystal elements through the light guide system. This multi-functionality reduces the total number of photodetector channels needed while maintaining comprehensive signal collection coverage across the detector array.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design effectively reduces the number of silicon photomultiplier tube arrays and signal channels, thereby decreasing the circuit scale and equipment costs while maintaining the detection quality and image resolution.
Implementation Method 1
After the rays hit scintillators, scintillation fluorescence is generated
Implementation Method 2
a layer of light guides is added between a crystal array and a silicon photomultiplier tube array, and the light is distributed with the aid of the light guides
Implementation Method 3
The scintillation fluorescence is converted into an electrical signal by the photoelectric conversion device
Implementation Method 4
replacing some with high-reflectivity material blocks and using a layer of light guide sheets between the scintillation crystal array units and the silicon photomultiplier tube array units, which assists in light collection and ensures that fluorescence is effectively captured
Data Source
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AI summary
Provided is a PET detector for reducing the number of silicon photomultipliers in use, which is characterized in that: the detector comprises layers respectively formed by a scintillation crystal array unit and a silicon photomultiplier (4) array unit, the scintillation crystal array unit and the silicon photomultiplier (4) array unit are rectangular cross sections in plan view, and the scintillation crystal array unit and the silicon photomultiplier (4) array unit have the same area of the rectangular cross sections in plan view; the scintillation crystal array unit consists of a plurality of scintillation crystal strips (1) parallel to each other, free of gaps and attached to each other on sides, the scintillation crystal strips (1) are all cuboids with uniform length, width and height; the silicon photomultiplier (4) array unit is an array assembly, which is formed by M silicon photomultiplier (4) arrays and has the rectangular cross section in plan view.