Norrby Formulas for IOL Power Calculation

This chapter gives Norrby’s background in optics as researcher working for a major international IOL manufacturer and his early and subsequent work in the optics and development of IOL power calculation formulas. He has developed three formulas for IOL power (Norrby thick lens formula, Norrby thin lens formula, and Norrby regression formula), which are thoroughly documented here. This comprehensive effort was first presented a decade ago but never published until now, in this chapter. Since he has now completely retired from the field, it will be up to others to test the benefit of his theories in clinical practice and compare them to the other new formulas using artificial intelligence and special algorithms.