Optical Wavelength Meter Calibration Using Iodine Stabilized He-Ne Laser by Direct Measurement Method

Abstract

Non-stabilized He-Ne lasers are widely used in calibration laboratories and industries. Wavelength calibration is a requirement to know the real wavelength of a non-stabilized He-Ne laser and its deviation. More importantly, calibration process creates a traceability link from the calibrated device to the primary standard of length measurement. One major wavelength calibration method for non-stabilized He-Ne lasers is using direct measurement method which requires a wavelength meter. The wavelength meter has to be calibrated first using a stabilizedHe-Ne laser prior to its use. The recommended radiation power of the stabilized laser in RCM-LIPI, IodineStabilized He-Ne Laser (KIM-1), is (50 ± 25) μW. Here, we examine the calibration process of the high precision wavelength meter with a measurement range of -25 dBm to +10 dBmor equals to 3.16 μW to 10 mW for a wavelength measurement range of 600 nm to 1650 nm. Several uncertainty evaluations for measurement were applied to assess the wavelength meter's performance. The results show that the wavelength meter produces a wavelength reading that is still within the desired band of measurement, thus making it a valid measurement instrument to calibrate the wavelength of non-stabilized He-Ne lasers with 10-3 nm of resolution. The wavelength meter's measurement capability can also be traced back to the length main standard, Iodine Stabilized He-Ne Laser (KIM-1).