Pixel Bleeding Correction in Laser Scanning Luminescence Imaging Demonstrated Using Optically Stimulated Luminescence

Area of Science:

• Medical Physics
• Materials Science
• Image Processing

Background:

• Laser scanning imaging techniques like X-ray imaging and 2D dosimetry can suffer from "pixel bleeding."
• This artifact is caused by slow luminescence centers in materials such as photostimulable phosphors and optically stimulated luminescence detectors.
• Existing limitations in readout speed hinder the application of certain materials, like Al2O3 films, in 2D dosimetry.

Purpose of the Study:

• To develop and evaluate an algorithm for correcting pixel bleeding in laser scanning imaging.
• To enable faster readout speeds for Al2O3-based X-ray detectors used in 2D dosimetry.
• To explore the potential of new materials in laser scanning applications by mitigating luminescence lifetime constraints.

Main Methods:

• A deconvolution algorithm was designed, incorporating the lifetime of slow luminescence centers.
• The algorithm utilizes detection of both fast and slow luminescence signals and combines data from opposite scanning directions.
• Simulated data and experimental validation using Al2O3:C and Al2O3:C,Mg X-ray detector films were employed.

Main Results:

• The algorithm effectively corrects pixel bleeding caused by slow luminescence centers.
• Readout speeds for Al2O3 film detectors were increased by 300-500 times compared to conventional limits.
• The method demonstrated successful image reconstruction for Al2O3 detectors previously limited by slow luminescence.

Conclusions:

• The developed algorithm significantly improves laser scanning imaging performance by addressing pixel bleeding.
• Faster readout capabilities open avenues for using novel materials in 2D dosimetry and X-ray imaging.
• Further investigation into noise effects is recommended for specific applications of this algorithm.