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ArcticMyst Security by Avery

How long would it take for eye to get damage by laser reflection?






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We get far too many of these from new members who have one or two posts to be a coincidence. It is often a banned member coming back with really silly questions. No surface that can't reflect light can cause damage to your vision. You might get flash blinded if the power is very high, but that is tantamount to what you see after having flash photography of you in a darkened area. Those cheap "military" pointers have less than 100 mW of power and won't do it.
 

Encap

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If say i was to shine my laser around in a lit room and it reflected off like a white dress shirt or white rag, would that reflection damage my eyes. My laser is from ebay - Military 20 Miles Blue Purple 405nm Laser Pointer Pen Visible Beam+18650+Charger | eBay

Would it damage my eyes even if i had those cheap laser safety glasses?

Thank you for your time. I just want to make sure and be safe.

To answer the question in your post Title---if a laser was going to damage you eyes--if it directly hit you in the eye from close eough distance to to damage-- the damage would happen in less time than the human blink refex of 0.25 seconds/ at the speed of light--no way to avoid it or no time make any correction ---that is why laser goggle are so important to protect your eyes

Re: your post question ---Probably not--no as Paul has said with your low power low cost ebay 405nm laser.

Next time you buy a laser you might want to consider one that you can see more easily--- is brighter to human eyes/ human visual system---at same output power> 405nm is only 10% as bright to the eye as 445nm blue which is only about 10% as bright as 532nm green--all all 3 wavelengths same W or mW output power

HAve a look at this chart if you are interested in eye safety with lasers : http://www.lasersafetyfacts.com/resources/FAA---visible-laser-hazard-calcs-for-LSF-v02.png
 
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diachi

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We get far too many of these from new members who have one or two posts to be a coincidence. It is often a banned member coming back with really silly questions. No surface that can't reflect light can cause damage to your vision. You might get flash blinded if the power is very high, but that is tantamount to what you see after having flash photography of you in a darkened area. Those cheap "military" pointers have less than 100 mW of power and won't do it.


Just to be picky, but the diffuse reflections from a scope can be intense enough to cause eye damage from several meters. :p :beer:

But under these circumstances, yes, you're correct. Anything more than a meter or two is very likely safe.
 
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What does that mean? What kind of scope and reflection? If it is glass or reflective, then yes. What kind of diffuse reflection are you referring to?
 
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Just to be picky, but the diffuse reflections from a scope can be intense enough to cause eye damage from several meters. :p :beer:

But under these circumstances, yes, you're correct. Anything more than a meter or two is very likely safe.

What does that mean? What kind of scope and reflection? If it is glass or reflective, then yes. What kind of diffuse reflection are you referring to?
Yeah me too... Not sure where the scope comes
into play... (perhaps alcohol was involved).:D

The diffuse reflections from a white dress shirt or
white rag as the OP mentioned I would assume.

If the OP is wearing even cheap but wavelength
appropriate Laser Safety Goggles/Glasses he would
be protected against stray reflections of those
surfaces... IMO

Jerry
 

CurtisOliver

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Endured exposure to diffused bright light can cause eye strain, and temporary vision problems. But won't cause any long term problems.
But it should be noted that you need to be careful with near UV pointers.
 
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405 nm pointers scare me for these four reasons:

1. They are so close to UV they pack a powerful punch to damage cells, probably far more than any of the longer wavelengths of the same power output.

2. Due to the short wavelength and being single mode (all of the 405 nm laser diodes I know of are) the beam can be focused to a much smaller point to produce more damage due to increased power density.

3. Due to both the short wavelength and being produced by a single mode diode, the beam does not diverge very quickly compared to other laser pointers, causing even more at distance power density to more easily produce harm.

4. Due to our eyes being only one percent as sensitive to 405 nm, compared to green, the outputs can appear fairly weak when they are in reality producing a large amount of power.


Due to the above, if proper care isn't taken, these diodes can produce greater hazards than the longer wavelengths of the same power output.
 
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CurtisOliver

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Also two other points:

Due to their reduced brightness, it is easy to underestimate the power and danger of 405nm, similar to how we treat NIR lasers.
Also, the fluorescence and wavelength can make difficult viewing and you will notice difficulty focusing on the dot from a distance.
 
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I thought of the weak appearance and edited that in while you were posting, yep, that is a biggie. You are right about focus, I can't focus on near UV to see that WL very well, not sure if that is common or just age related.

When editing a post, you cannot see new posts came in, I don't know why the forum software does that, but I had to go out of the thread and see using the "new posts" link that you had added to the thread.
 
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CurtisOliver

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Not age related from what I can tell. :p
I find that the laser goes from a clean dot to a round blur once around half a meter away.
 




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