Physical design of photon-counting mode γ-ray large object radiation imaging system

Area of Science:

• Nuclear instrumentation and methods
• Radiation detection and imaging
• Photon counting techniques

Background:

• Existing large object radiation imaging systems suffer from image quality deterioration due to the inability to distinguish effective signals from noise and scattered photons.
• Current-integration mode detectors in conventional systems are limited in differentiating signal from interference.

Purpose of the Study:

• To design and develop a novel photon-counting mode γ-ray large object radiation imaging system.
• To overcome the limitations of current-integration systems by enabling energy analysis for signal discrimination.
• To ensure system functionality under high-intensity radioactive sources (up to 300Ci Co-60).

Main Methods:

• Designed a system based on LYSO and SiPM photon-counting detectors.
• Developed specialized filter circuits (ZP-SK and (ZP)2-SK) for high-intensity Co-60 sources.
• Implemented energy analysis and photon counting using a voltage comparator and FPGA.

Main Results:

• The photon-counting system achieved a significant improvement in Steel Penetration (SP) by 60-70 mmFe compared to current-integration systems.
• This improvement is equivalent to increasing the radioactive source intensity by 13 to 20 times.

Conclusions:

• The photon-counting mode γ-ray imaging system offers substantial improvements in radiation image quality and penetration ability.
• The developed system holds significant potential for advanced applications in large object radiation imaging.