Would it be safe to look at 1.6W dot?

[BShanahan14rulz]

So, the answer is, "It depends." What's all the argument about?

Lots of power emitted from a small point is bad. The more power or smaller the point, the worse it is. Just say "It depends," and ask an open-ended question about the original poster's valuation of one of their eyes; of both of their eyes.

http://dukemil.bme.duke.edu/Ultrasound/k-space/img210.png here's a nice picture

 

[firelaser]

its all about the energy density hitting your eyes.. it may spread over a 3 feet perfectly and just be painfully bright, or there might be a tiny piece of shiny stiff.. like glitter or glass that will take 1% or more of that 1000mw laser giving you 10mw of eye laser dangerous ,,,(this is assuming you are an expert on what is shiny in your room!) so if you point your 1 W blue at your ceiling there may be a .1 % chance one of you may get that shiny reflection.. if your outside and pointing it at clouds.. then the chances are infinitely lower.. , you gotta worry more about those flying blinking lights now than your own eyes... always loof for the flying blinking lights lol.

 

[paul1598419]

About a week ago I went back and looked up this same argument being posted about 8 months ago, and according to the University of Chicago Office of Radiation Safety, and partly taken from ANSI ZI 36.1 of the American National Standard for the Safe Use of Lasers, starting on page 8, 3b Diffuse Reflections, they set up a mathematical experiment that proved a 2 watt 532nm DPSSL shown on a white piece of paper and viewed from 15.75 inches at an angle of 20 degrees from normal, The power output H=0.1mJ/cm^2 was the amount exposed to the eyes and was considered safe. Actually, if you think about it, a reflection from a diffuse surface is viewable from every angle one could observe it from. I this case, the light is decreasing at a rate of the inverse of the square of the distance it is viewed from. This is of course assuming that the surface is diffuse. If there is something that can reflect specular reflections then the power is very much higher if the beam is directed at the eyes. It was Atomicrox's post that led me to this publication.