Fiber Bragg grating-driven subpixel jitter correction for enhanced SECM imaging stability

Spectrally encoded confocal microscopy (SECM) uses diffraction gratings for high-speed imaging, but spectral jitter from swept-source lasers affects stability. We developed a subpixel jitter correction method using fiber Bragg grating (FBG) signals acquired through a high-speed digitizer. By interpolating and aligning the FBG signal, we achieved precise jitter compensation. This jitter correction can be performed in real-time using graphical processing unit-based parallel computing, allowing 1400×1400 pixels to be displayed and stored at 50 Hz. Our approach outperformed traditional hardware-based triggers, achieving spectral jitter-induced absolute pixel variation of 0.250±0.205 pixels compared to 0.607±0.415 and 0.549∓0.352 pixels for digital triggers using laser output and FBG, respectively, allowing significantly less jitters with a p-value of <0.0001.