V-Number calculator
Normalized frequency and mode count of a step-index fiber.
Category: Fiber Optics
Formula: V = (2π·a/λ)·NA · single-mode if V < 2.4048 (first zero of J₀)
Inputs
| Input | Parameter | Unit | Default |
|---|---|---|---|
| Core radius | a | µm | 4.1 |
| λ | lam | nm | 1310 |
| NA | NA | 0.14 |
Result with the default inputs
- V: 2.7531
- Modes (≈ V²/2, large V): 3.7898
- SM cutoff λ: 1499.7131 nm
Open it with your own values: put each input in the address as a parameter, for example /calculators/v-number?a=4.1. A unit other than the listed one goes in <parameter>_unit.