Enter the phase constant and the wavenumber into the Calculator. The calculator will evaluate the Effective Refractive Index.

## Effective Refractive Index Formula

ERI = B *w/(2pi)

Variables:

- ERI is the Effective Refractive Index ()
- B is the phase constant
- w is the wavenumber

To calculate Effective Refractive Index, multiply the phase constant by the wavenumber, then divide by 2 times pi.

## How to Calculate Effective Refractive Index?

The following steps outline how to calculate the Effective Refractive Index.

- First, determine the phase constant.
- Next, determine the wavenumber.
- Next, gather the formula from above = ERI = B *w/(2pi).
- Finally, calculate the Effective Refractive Index.
- After inserting the variables and calculating the result, check your answer with the calculator above.

**Example Problem : **

Use the following variables as an example problem to test your knowledge.

phase constant = 34

wavenumber = 1234