[7p-N221-1~11] 3.7 Optical measurement, instrumentation, and sensor

3:15 PM - 3:30 PM JST(6:15 AM - 6:30 AM UTC)

[7p-N221-7] Dispersion Tuned Swept Laser Setup and Optimization for OCT

〇(M2)Hongxu Chen¹, Yifan Ma², Naoki Yamaguchi², Sze Yun Set², Shinji Yamashita¹ (1.Tokyo Univ., 2.Rcast)

Keywords:

imaging,Wavelength swept laser

This study presents a dispersion-tuned swept laser system optimized for Optical Coherence Tomography (OCT). Traditional wavelength tuning using mechanical filters limits sweep speed. To address this, we used a chirped Fiber Bragg Grating (cFBG) and an LN intensity modulator for active mode-locking. By adjusting the modulation frequency, the system can sweep wavelengths based on cavity dispersion.A 10.1-meter cavity with a semiconductor amplifier (BOA1004P) achieved an 80 nm sweep range at speeds up to 125 kHz. An interferometric setup simulated OCT performance, showing good signal roll-off up to 1.5 mm at lower modulation frequencies. When the modulation frequency was increased to 1.39 GHz, the imaging depth extended to 2.5 mm. This setup allows both high-speed and wide-range sweeping, suitable for high-resolution OCT imaging.