refractive index that is defined as n = n0 + κ where n0 is the "standard" refractive index, and κ is the optical extinction coefficient; the optical extinction coefficient "indicates the amount of attenuation when the electromagnetic wave propagates through the material", murdetegur, mis on määratletud kui n = n0 + κ, kus n0 on tavaline murdumistegur ja κ on optiline sumbuvustegur, mis näitab sumbumise ulatust, kui elektromagnetlaine levib läbi materjali