品质因数(Q)是光学谐振腔的重要参数,大尺寸的平面环形谐振腔有着更大的单圈损耗,却具有更高的Q值。针对这个问题,从光子寿命的角度对环形谐振腔耦合结构进行了建模分析与仿真,提出了用等效单位传输损耗参数来表征谐振腔的腔长与品质因数之间的关系。设计、加工了不同腔长(3.1,9.5,12.6和18.8 cm)的氧化硅光波导环形谐振腔,其中谐振腔的耦合系数保持不变,测试结果显示:随着谐振腔的腔长增加,谐振腔的等效单位传输损耗降低,Q值增大,与仿真结果相符。该结论为高Q值光波导谐振腔的研究提供了一种新的途径。 The quality factor (Q) is an important parameter for optical resonators. Large planar toroidal resonators have larger single-turn losses but higher Q values. In order to solve this problem, the ring resonator coupling structure was modeled and analyzed from the perspective of photon lifetime, and the relationship between cavity length and quality factor was proposed by using equivalent unit transmission loss parameters. The ring resonator with different cavity lengths (3.1, 9.5, 12.6 and 18.8 cm) was designed and fabricated. The coupling coefficient of the resonator remained constant. The test results showed that with the cavity length increasing, the resonance Cavity equivalent unit transmission loss is reduced, Q value increases, consistent with the simulation results. This conclusion provides a new way for the study of high-Q optical waveguides.