Page 348 - Blog Posts v1

E60 - Calibrating your laser - making sense of the numbers...
How do you calibrate your lasers so that the numbers on your laser screen actually mean something useful?
Well, there is a process which you need to follow. The video shows this process in detail.
https://youtu.be/wxlpklKwZ8Y
So, you need to measure the laser energy for each of your 'input' settings using an energy meter designed for Q-switched pulses. I usually record three measurements for each input setting, and then average them.
Then you fire the laser at some burn paper (or a dark photo in a magazine will do). You then measure the diameter of these spots. I generally fire three spots at two or three different energies, just to see if there is much variation.
You tend to find that the higher energies will deliver slightly larger spots, just because the laser-generation process is more efficient inside the crystal.
Knowing the energies and spot diameters for each input setting, you can then calculate the fluence (energy density = energy / spot size area) for each setting.
Mike’s Blog Posts 348