Senior Member
I have a nice little black bug that follows me around because I was stupid and took 35mw of red in the eye off axis. Fortunately my brain takes care of it for the most part but it could have been much worse. Read that again 35mw 660nm..... We play with 5000-20000mw these days. I count myself lucky and it reminds me to wear my gear.
Senior Member
that's good to hear it did not do disabiltating damage.
as i understand it even a 5mw is the threshold for damage. oddly that reminded me of an unsafe and stupid use of a pointer i had, a 300mw green, in our lab at work i was showing off the laser. it was 2003 era 300mw green laser, i saw a bug crawling on the floor and i cooked it with the laser, on white tile i felt like i needed a welding mask as i was lucky i did not damage my vision or any one else in the lab. it had not sunk in at that time to how careless that action was, that would have been damage by specular reflection if i remember right
edited for clarity
Last edited by Draco; 11-12-2015 at 03:12.
Remember Remember The 8th of November, When No One Stood, but Kneel, In Surrender
In a popular government when the laws have ceased to be executed, as this can come only from the corruption of the republic, the state is already lost. Montesquieu
Senior Member
don't know why i typed that, i guess my intent was to show how stupid it was for me to-do and to not ever repeat with out glasses and to leave bugs just doing there thing alone too.
some times my posts dont come out as i had originally intended them to be
Remember Remember The 8th of November, When No One Stood, but Kneel, In Surrender
In a popular government when the laws have ceased to be executed, as this can come only from the corruption of the republic, the state is already lost. Montesquieu
Believe it or not, diffuse reflections off surfaces like walls and floors are not nearly as hazardous as you might expect. One of the practice questions that we went over in the LSO class dealt with close viewing (18 inches away from the wall) of a laser spot on a white, painted wall. The laser was positioned across the room, and I if I remember the question correctly it was a 4 watt YAG with fairly wide divergence that yielded a spot size close to 1 inch.
Anyway, when you ran the numbers, the diffuse reflection off the wall was actually eye-safe (albeit just barely). However, common sense would tell you that the spot would be blindingly bright and stupidly painful to look at, so it would be unlikely that you would be able to stare at it for very long. (Indeed, the calculation assumed a .25 second exposure, since you would almost certainly blink involuntarily when exposed to such a bright spot.)
Still, most everyone in the class was quite surprised to see that the irradiance was actually within the acceptable limit.
Adam
Posting Permissions
Reply With Quote
buffo