Use this simple abbe number (V-number or constringence) calculator to measure of the material's dispersion, with high values of V indicating low dispersion in optics and lens design.
| λ in nm | Fraunhofer's symbol | Light source | Color |
|---|---|---|---|
| 365.01 | i | Hg | UV |
| 404.66 | h | Hg | violet |
| 435.84 | g | Hg | blue |
| 479.99 | F' | Cd | blue |
| 486.13 | F | H | blue |
| 546.07 | e | Hg | green |
| 587.56 | d | He | yellow |
| 589.3 | D | Na | yellow |
| 643.85 | C' | Cd | red |
| 656.27 | C | H | red |
| 706.52 | r | He | red |
| 768.2 | A' | K | IR |
| 852.11 | s | Cs | IR |
| 1013.98 | t | Hg | IR |
Formula:
VD = (nD - 1) / (nF - nC)
where,
nD, nF and nC - the refractive indices of the material at the wavelengths of the Fraunhofer spectral lines of D-, F- and C respectively.
VD - abbe number of material