21 Apr Laser Safety & Power Levels
Aug 21, 2007
Here’s a photo from a couple of months ago when we were testing a relatively small laser diode:
“Relatively small,” though, is a relative term. Lasers are classified in various levels according to their potential for biological (primarily eye) damage. Class 1 lasers are the safest ones, and include things such as the lasers found in CD players (partially because they’re enclosed and don’t activate with the unit open). The classes go up from there, through 2, 3a, 3b and finally to class 4. Class 4 lasers are dangerous for any amount of exposure (whereas some of the lower levels are safe up to, for example, 0.25 seconds exposure), and generally include lasers of more than 0.5 watts. Given the power requirements of the competition, any laser-based entry (such as ours) will be using power levels thousands of times higher than 0.5 watts. The test shown above had a power output on the order of 10 watts (I don’t remember the exact numbers offhand).
So while the photo above is for a laser that is very small compared to what we’ll be using for the competition, it’s still large enough to be very safely into the Class 4 category. Hence I often refer to the tens-of-watts bars that we’ve done testing with as “small” but laser safety people think of those as “large.” I will have more to say about laser safety in the future.