This standard specifies two reference wavelengths used to represent optical materials, optical systems, optical instruments, and spectacle lenses, and specifies the main refractive index, main dispersion, and the Abbe numbers of the two reference wavelengths and main dispersion.
GB/T 10050-2009 history
2009GB/T 10050-2009 Optics and optical insturments.Reference wavelengths
1988GB/T 10050-1988 Optics and optical instruments--Reference wavelengths