2012/11/12 by Jitao Zhang, Pei Huang, Yan Li +1 · 12 citations
Decision Sciences · Engineering · Physics and Astronomy · #Advanced Measurement and Metrology Techniques #Advanced Sensor Technologies Research #Computer science #Instrumentation (computer programming) #Materials science #Optics #Physics #Range (aeronautics) #Refraction #Refractive index #Refractometer #Refractometry #Scientific Measurement and Uncertainty Evaluation #Wavelength #physics.ins-det #physics.optics
paper · pdf · doi:10.1364/ao.52.003671
published in Applied Optics 52(16), 3671 (Optica Publishing Group) · 12 pages,7 figures
arxiv created 2012/11/12 · openalex publication_date 2013/05/20 · arxiv updated 2013/12/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present a refractometer that is capable of measuring the refractive index of gases with an unambiguous range of 1.000395 and an uncertainty of 3.14×10(-8) at 633 nm. The measurement range was extended via the combination of the vacuum cells according to the proposed synthetic pseudo-wavelength (SPW) method. The basic principles of the SPW method and the design of the gas refractometer are presented in detail. The performance of the refractometer was verified in the measurements of dry air, nitrogen gas, and ambient air under different environmental conditions. No gas-filling or pumping processes were required during the measurements; so one measurement could be completed within 70 s. Compared with existing refractometers, the method reported here holds advantages in its large unambiguous measuring range, fast speed, high accuracy, and simple instrumentation design.