中国的国家长度基准:稳定在^(127)I_2超精细结构上的633nm He-Ne激光(续)——现代计量科学专题之三

The Primary Standard of Length in China——Stabilized to Hyperfine Structure Components of^(127)I_2 He - Ne Laser at 633nm

4新一代碘稳频激光系统 进入20世纪90年代以来,由于技术的不断进步,在计量学领域,633nm稳频He-Ne激光被广泛使用.基于三次微分技术的碘稳频He-Ne激光除了在传统意义上用于计量标准的目的外,也开始进入到一些有特殊精度要求的测量系统中.

Metre-as a length primary unit, its definition has been changed two times since it first has been definited in 1889.The principle of Iodine stabilized He- Ne laser system at 633nm to realize the definition of metre has been introduced. New improvement of the primary standard in our country including the optic - mechanical structure and the electrical system to recognize and lock - in for absorption peaks of Iodine automatically has been described. The results of international comparison of the system have been given.