Clarify the "dot viewing" fear?

[chipdouglas]

now... lets ignore all the numbers and go strictly off of common sense.

if you stare at the dot your eyes are straining to adjust to the brightness. do you think it is safe to strain your eyes? is it even worth trying to find out a safe distance?

i went and pulled the relevant post from your thread from 2009 twhite. it was written by jerry.

What you need to remember is that a laser beam does not diverge very much...

If you are looking at let's say a 100mW laser beam's dot on a Black Flat surface...

there will be a very low powered reflected beam... and would be much safer than

looking at the same dot on a White or even highly reflective surface..



The amount of reflection would only be measurable knowing the exact reflectivity

of the surface in question...

If the surface is a Front Surface Mirror.... the amount of the Laser's reflected beam

would come near 100% ...



That would be considered dangerous...



To avoid making a mistake or inadvertently shinning a Laser's beam onto a reflective

surface... Laser Saftey Goggles are a must....





BTW.... to the Forum...





Jerry

 

[LtKernelPanic]

There was a recent thread that indadvertedly showed the "dot danger" pretty well. I forger whose picture it was but IIRC it was in "show your rainbow" picture where the lasers were shining at a wall and there were two very clear reflections with a possible third coming back at the camera. I'll try to find the picture later unless someone beats me to it.

edit:

Found it. I was also mistaken about what the lasers were pointed at. It appears the door (not a wall) has a slight sheen to it so it will reflect more than normal flat wall paint. You can still clearly see the blue and yellow beams reflecting back to and hitting the wall on the right side. I'd be curious what the power of those is. It looks like there's also a red reflection going towards the top left of the frame too.

http://laserpointerforums.com/f48/somewhere-over-rainbow-60645.html#post863677