Full Description JIS B 7072-2:2020 specifies a measuring method in which the variation of optical path length with temperature change of optical glass is read by the number of periods of brightness changes of interference fringes using the interferometry method, and the temperature coefficient of refractive index is calculated from the variation of the optical path length.
JIS B 7072-2:2020 history
2020JIS B 7072-2:2020 Measuring method for temperature coefficient of refractive index of optical glass -- Part 2: Interferometry