非稳腔腔镜准直度判定的新方法

New criterion for alignment degree of cavity mirrors in unstable resonator

腔镜准直是实现非稳谐振腔正常工作的前提。目前,对非稳腔腔镜准直采用的最普遍的方法是人工调腔,该方法过于依赖人的主观认识和经验水平,因此调腔精度十分有限。为了对导引光近场干涉条纹的对称性进行更加客观准确的判断,提高非稳谐振腔腔镜的准直精度,提出了一种对条纹图在水平和垂直方向上进行灰度投影,并以投影曲线中各级峰(谷)值位置的距离来表征条纹对称度的方法,由此编制的计算程序简单可靠,可以实现对调腔精度的实时检测。大量的实验结果表明,此方法能够明显提高调腔精度。

Aligning the cavity mirrors is a premise to stabilize the operation of unstable resonator. The common method for the alignment degree of cavity mirrors in unstable resonator is manual regulation, which depends on man＇s subjectivity and experience, thus the corresponding precision is greatly limited. In order to verify more objectively and accurate whether the near-field interference fringes of guided light are symmetrical or not, a new criterion was proposed. By projecting the gray of interference fringe pattern in horizontal and vertical, and using the location＇s distance of the projection curve＇s peak （valley） values, fringes＇ symmetrical information was represented. Based on the criterion, the compiled calculation program was simple and reliable, which can realize real-time monitoring on the alignment degree of cavity mirrors. A great deal of experimental results show that it can significantly improve the alignment precision of the resonator.