Lens Materials. ABBE Values, & Index of Refraction
Memorize this chart, it will not only help you with test questions but help dispense the correct material for a patient.
Remember that the higher the ABBE Value the less chromatic aberrations in a lens.
The Higher the Index of Refraction, the less material is needed in a lens to refract light so the thinner it will be.
| Material | ABBE Value | n |
| Crown Glass | 58 | 1.52 |
| CR39 | 58 | 1.49 |
| Polycarbonate | 31 | 1.59 |
| Trivex (Mid-Index) | Roughly 44 | 1.53 |
| Hi-Index Lenses | 31-42 (Depends on Index/Manufacturer) | 1.60, 1.67, 1.70, 1.74 |
| Diamond | 22.73 | 2.4 |
| Water | 1.33 | |
| Flint Glass | Roughly 52.5 | 1.66 |