TRACEABILITY OF 633 nm LASER CALIBRATION AT NIMT
نویسندگان
چکیده
− The National Institute of Metrology (Thailand), NIMT, maintains the standard of length in accordance with the definition of the meter through a 633 nm iodine stabilized He-Ne laser. Its accuracy is transferred to stabilized and non-stabilized lasers regarding to beatfrequency method and direct measurement using a wavelength meter, respectively. The traceability in wavelength measurement at the NIMT is discussed here. The iodine stabilized He-Ne laser is self-calibrated using the master and slave beat frequency system. NIMT participated in APMP.L-K11 intercomparison and the results are presented. The standard uncertainty is 2.5x10.
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