About this calculator

This calculator computes the round trip time and repetition frequency of a pulsed laser cavity. The cavity can consist of up to four different materials with different group indexes and with either single or double pass through them. A ring cavity is an example of a single-pass cavity while a linear cavity is a double-pass cavity.

First, the physical lengths and group indexes of the materials comprising the cavity are used to calculate the optical path length of a single round trip as follows

The round trip time is then the optical path length divided by the speed of light in vacuum

and the repetition frequency is the reciprocal of the round trip time