基于偏振混叠的氦氖激光器纳米测尺系统

摘要

提出一种基于偏振混叠的氦氖激光器纳米测尺系统,将双折射元件插入He-Ne激光器谐振腔内产生频率分裂,使激光器变成了频差可调的双频激光器.运用频率分裂、模竞争、双纵模功率调谐等激光物理效应,使用偏振混叠方法和设定浮动阈值,研制了新型的激光器纳米测尺.以激光波长为尺子,具有可溯源性,在没有任何电细分的条件下达到了纳米量级的分辨率,与激光干涉仪的比对实验表明,该系统的分辨率为79 nm,量程为20 mm,线性度为5.8×10-5,标准差为520 nm.%A novel kind of dual longitudinal mode He-Ne laser nanometer scale measurement system based on polarization mixture was put forward.With the inserted birefringence element,the frequency splitting effect will occur inside the He-Ne resonant cavity,which makes the laser turn into the dual-frequency laser with adjustable frequency difference.By using frequency splitting effect,mode competition effect and double longitudinal mode power tuning effect of laser physics,a new type of laser nanometer measurement ruler was proposed by using polarization mixing and floating threshold setting.The laser wavelength is applied as a ruler with traceability,leading to the nanometer scale resolution without electrical subdivision.The experimental results demonstrate that this system has the optical resolution of 79 nm,the measuring range of 20 mm,the linearity of 5.8×10-5 and standard deviation of 520 nm.