Optics & Photonics Talk

hello

I'm doing a project for my master study in electrical engineering.
My Project is a simple free space optical communication system.

Choosing and applying a laser in free space communication needs to consider safety issues. Most of commercial lasers are in class IIIb and I want to know how I can apply 

You have to ensure that the power level leaving your system does not exceed the limits for class 1 or 1M. There are formulas for the MPE for each wavelength and pulswidth combination in the ANSI Standard. That means you need to have at least one fail-safe also.

An important question is if you will have enough power to do your project with just a class 1 output. The MPE is higher for certain wavelengths as you can see in the standard,so you will need to design the system to meet safety and performance requirements. At a previous employer, we actually patented ways to do this for different applications.