This standard applies to the spherical radius of optical parts.
GB/T 3158-1982 history
1982GB/T 3158-1982 Radii of spherical surface of optical elements series of numerical values
GB/T 3158-1982 Radii of spherical surface of optical elements series of numerical values was changed to JB/T 10570-2006 Radii of spherical surfaces of optical elements series of numerical values.