Image reconstruction algorithm for laser-induced ultrasonic imaging: The single sensor scanning synthetic aperture...

Area of Science:

• Biomedical Imaging
• Acoustics
• Optical Physics

Background:

• Laser-induced ultrasound imaging is crucial for non-destructive testing and biomedical applications.
• Conventional reconstruction methods like delay-and-sum and time reversal suffer from artifacts, limiting image quality.
• Synthetic Aperture Focusing Technique (SAFT) offers improved resolution but requires complex implementation.

Purpose of the Study:

• To implement and evaluate a novel Single-sensor Scanning Synthetic Aperture Focusing Technique (SSSAFT) for laser-induced ultrasound imaging.
• To address limitations of existing reconstruction algorithms, specifically sidelobe artifacts and comet tail signs.
• To enhance image clarity and reduce computational load in ultrasound tomography.

Main Methods:

• Developed SSSAFT incorporating sensor size and detection procedures into SAFT algebra for circular scanning with a single acoustic sensor.
• Validated the method numerically using Green's function for the ultrasound wave equation.
• Experimentally tested SSSAFT on polylactic acid objects and a biological phantom containing a rat heart.

Main Results:

• SSSAFT effectively removed sidelobe artifacts and comet tail signs, leading to more distinguishable targets.
• The proposed method demonstrated faster performance and a lower computational load compared to time reversal and conventional delay-and-sum algorithms.
• Achieved superior image quality with enhanced clarity and reduced noise.

Conclusions:

• SSSAFT presents a significant advancement in laser-induced ultrasound imaging reconstruction.
• The method offers a practical and efficient solution for high-quality image generation in photoacoustic microscopy.
• SSSAFT holds potential for broader applications in non-destructive evaluation and biomedical diagnostics.