# Pulse train calculator

## About this calculator

This calculator computes various useful properties of an optical pulse train. The input parameters are the pulse duration, repetition rate, average power and, optionally for intensity calculations, the spot diameter. First, the calculator gives the duty cycle $D$, which is the product of the pulse duration $T$and repetition rate $f$ and essentially tells how much of the time the optical power is "switched on".

Then the calculator also computes the pulse energy, which is the average power divided by repetition rate:

Peak power is then simply pulse energy divided by pulse duration assuming a square pulse shape.

Pulse separation or the duration of the repeating cycle is the reciprocal of the repetition rate.

The intensities are calculated by dividing the power (either average or peak) by the spot area $A=\pi w^2$ where $w = d/2$ is the spot radius.