The Abbe number compares refractive strength with visible optical dispersion. The traditional reference lines are near nm, respectively. A large means weak relative dispersion.
An Abbe diagram plots refractive index against Abbe number to show available optical glass families. Many diagrams put increasing to the left. Ordinary crown glasses have larger than ordinary flint glasses, while modern compositions occupy a broader region.
Articles by others on the same topic
The Abbe number, also known as the V-number, is a measure of the optical dispersion of a material. It quantifies how much the refractive index of a material varies with wavelength.