Accurate and stable two-step LED position calibration method for Fourier ptychographic microscopy

Area of Science:

• Computational optical imaging
• Microscopy techniques
• Image reconstruction

Background:

• Fourier ptychography microscopy (FPM) achieves simultaneous wide field-of-view and high-resolution imaging.
• LED position errors in FPM degrade reconstructed image quality.
• Current LED position correction methods lack stability and accuracy for large misalignments or local optima.

Purpose of the Study:

• To improve the LED position model for FPM.
• To propose an accurate and stable two-step correction scheme (tcFPM) for LED position error calibration.

Main Methods:

• Developed an improved LED position model incorporating overall array offset and individual LED deviations.
• Implemented a two-step correction scheme (tcFPM): first correcting the overall array offset, then precisely adjusting individual LED positions.

Main Results:

• The improved LED position model accurately reflects actual conditions.
• tcFPM demonstrates high accuracy in correcting LED position errors.
• Simulation and experimental results show enhanced reconstruction stability and significantly improved image quality compared to existing methods.

Conclusions:

• A novel LED position error correction technology (tcFPM) is presented.
• The method offers a stable iterative process.
• tcFPM substantially improves the reconstruction accuracy of complex amplitude in FPM.