Dispersion-based interference fringe-order discrimination for long-range single-shot optical frequency comb...

We propose a fringe-order discrimination method for low-coherence single-shot optical frequency comb (OFC) interferometry. The method utilizes the chromatic dispersion effect of the refractive index of the resonator material, causing the OFC interval to vary with wavelength. By using two wavelength bands of a broadband light source through band-pass filters, fringe shift increases linearly with the fringe order. Around 19 fringe orders were resolved in the visible region, showing a ±1.5µm/order shift consistent with the theory. Experimental results also showed a reliable fringe-order shift in the near-infrared region. The method provides a simple, mechanically stable approach for a high-speed, single-shot imaging system.