Precise measurement of micro-dispersion for optical devices (optical fiber, lenses, etc.) holds paramount significance across domains such as optical fiber communication and dispersion interference ranging. However, due to its complex system, complicated process, and low reliability, the traditional dispersion measurement methods (interference, phase shift, or time delay methods) are not suitable for the accurate measurement of micro-dispersion in a wide spectral range. Here, we propose a spectral-interferometry-based diff-iteration (SiDi) method for achieving accurate wide-band micro-dispersion measurements. Using an optical frequency comb, based on the phase demodulation of the dispersion interference spectrum, we employ the carefully designed SiDi method to solve the dispersion curve at any position and any order. Our approach is proficient in precisely measuring micro-dispersion across a broadband spectrum, without the need for cumbersome wavelength scanning processes or reliance on complex high-repetition-rate combs, while enabling adjustable resolution. The efficacy of the proposed method is validated through simulations and experiments. We employed a chip-scaled soliton microcomb (SMC) to compute the dispersion curves of a 14 m single-mode fiber (SMF) and a 0.05 m glass. Compared to a laser interferometer or the theoretical value given by manufacturers, the average relative error of refractive index measurement for single-mode fiber (SMF) reaches 2.8×10−6 and for glass reaches 3.8×10−6. The approach ensures high precision, while maintaining a simple system structure, with realizing adjustable resolution, thereby propelling the practical implementation of precise measurement and control-dispersion.

中文翻译：

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基于光谱干涉测量的扩散用于高精度微色散测量


光学器件（光纤、透镜等）微色散的精确测量在光纤通信和色散干涉测距等领域具有至关重要的意义。然而，传统的色散测量方法（干涉法、相移法或时延法）由于系统复杂、工艺复杂、可靠性低，不适合宽光谱范围内微色散的精确测量。在这里，我们提出了一种基于光谱干涉测量的扩散（SiDi）方法，用于实现精确的宽带微色散测量。利用光学频率梳，基于色散干涉谱的相位解调，采用精心设计的SiDi方法求解任意位置、任意阶次的色散曲线。我们的方法擅长精确测量整个宽带光谱的微色散，无需繁琐的波长扫描过程或依赖复杂的高重复率梳，同时实现可调分辨率。通过仿真和实验验证了所提出方法的有效性。我们采用芯片级孤子微梳 (SMC) 来计算 14 m 单模光纤 (SMF) 和 0.05 m 玻璃的色散曲线。与激光干涉仪或厂家给出的理论值相比，单模光纤（SMF）折射率测量的平均相对误差达到2.8×10 −6玻璃达到3.8×10 −6 。该方法在保证高精度的同时，保持了简单的系统结构，实现了分辨率可调，从而推动了精密测量和色散控制的实际实现。