单腔双光梳绝对测距关键技术研究

Dual-comb distance measurement method with fast update speed and high precision is important development direction of comb-based distance measurement. However its application has limited by the complicated dual-comb source with large volume and weight, low environmental stability and priori estimation. In this project, we proposed a new distance measurement method based on a dual-comb oscillator, which is an integrated comb laser with significantly reduced complexity and cost for generating two combs with low noise due to the identical path. Firstly, a large repetition rate difference can be achieved by developing wavelength-multiplexed laser for further improving measurement speed to meet the requirement of rapid distance measurement. Secondly, the method will be studied to stabilize the repetition rate difference and reduce the noise to further improve the precision. Thirdly, the unambiguous distance can be enlarged by asynchronous optical sampling with the two different repetition rates simultaneously. Based on above researches, the ranging experiment as well as the dual-comb oscillator fabrication will be carried out to verify the effectiveness of the proposed dual-comb ranging method. The research of this project will provide a new way for rapid and precise absolute distance measurements..This project is the continuation of the applicant’s postdoctoral research, which will be list out in the section of research foundation.

双光梳测距方法具有快速测量和高精度的独特优势，是飞秒光梳测距的重要发展方向，在现有双光梳测距方法中，存在着光源系统结构复杂、光源同步困难、体积重量庞大、环境适应性差、需要先验距离等局限。本项目提出一种新的单腔双光梳绝对测距方案，利用脉冲在单一光纤腔内传播的高度相关特性实现共模噪声相互抑制的集成双光梳光源，显著降低双光梳光源的复杂度与成本；根据快速测距要求，研究波长复用等技术产生大重复频率差，进一步提高测量速度；研究大重频差稳定方法同时降低光源噪声，提高测量精度；提出本振和信号脉冲交替采样的测量方案，增大非模糊距离，避免先验距离。在此基础上，研制单腔双光梳光源，搭建测距装置并开展实验，验证该方法的有效性。本课题研究可望为双光梳快速精确绝对测距提供新的技术途径，具有重要的理论价值和应用价值。.本项目是申请人在博士后期间研究成果的延续和拓展，前期研究成果将在研究基础部分进行说明。

双光梳测距方法具有快速测量和高精度的独特优势，是飞秒光频梳测距的重要发展方向。为了解决现有双光梳测距方法中存在的光源系统结构复杂、需要先验距离等问题，本项目在研制单腔双光梳光源，搭建双光梳测距系统方面开展大量实验研究。在本项目的研究中，我们首先开展了基于单腔双光梳激光的生成方法的研究。通过利用双波长、偏振复用等复用机制下的碳纳米管和碲化钨被动锁模超快光纤激光器，实现了不同频率脉冲在同一光纤腔内共同振荡，获得了具有共模噪声相互抑制作用的重频差稳定的集成双光梳光源。其中，双波长双光梳激光器的频差由于腔内色散决定可获得较大重频差，满足快速测距的要求；偏振复用双光梳激光器的光谱之间具有良好的重叠，不需要对其进行非线性谱展宽便可直接应用于双光梳测量，适用于结构紧凑的测距系统。然后，我们开展了基于平衡探测的光学异步采样的互相关信号生成、数据采集和处理方法的研究，搭建了自由运转的单腔双光梳测距实验系统；首次提出并实验验证了一种本振和信号脉冲同时交替采样的远距离测量方法，突破了本振光重复频率对非模糊距离的限制，获得了超大测量范围，避免了距离先验问题。本项目探索并形成的单腔双光梳光源生成方法、交替采样超大非模糊距离测量方法，为结构紧凑双光梳快速绝对测距提供了新的技术途径，能够为今后复用双光梳激光器技术、双光梳测量技术提供一定的技术支撑，在激光雷达、环境监测、生物成像等诸多领域具有广阔的应用前景。