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Need suggestion about my 445 nm laser

moh17

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Oct 13, 2014
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I received a 445 nm laser pointer from Aliexpress. the seller claimed that it is only 10 mW. It is brighter than my 5mW green laser. It has no warning sticker. I found that it can burn through black cards, and CD cases. I'm afraid because I did not wear goggles while testing it. I did not get any direct hit. I'm afraid from reflection of white surfaces like wall also, my monitor screen is black; will it reflect the full power ?. My vision does not changed; is there any chances of a damage from white surfaces like a wall from short distances 3 or 4 meters ?. I'm really afraid.
 





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I received a 445 nm laser pointer from Aliexpress. the seller claimed that it is only 10 mW. It is brighter than my 5mW green laser. It has no warning sticker. I found that it can burn through black cards, and CD cases. I'm afraid because I did not wear goggles while testing it. I did not get any direct hit. I'm afraid from reflection of white surfaces like wall also, my monitor screen is black; will it reflect the full power ?. My vision does not changed; is there any chances of a damage from white surfaces like a wall from short distances 3 or 4 meters ?. I'm really afraid.

That isn't a good place to buy lasers. There isn't any 445nm that's only 10mW as far as I know. 10mW is a small fraction of the power needed to burn stuff. Your eyes are ok, don't worry, just don't look at the dot while burning anything and don't look at it up close, put your goggles on for that. Just be careful of reflective surfaces like glass, mirrors, metal etc. if you shine it across the room you should be able to tell if the dot is too bright to look at, if there is any doubt then don't look at it. If you are still seeing after images for a few seconds then you are pressing your luck. :tsk:

Alan
 

moh17

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Oct 13, 2014
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That isn't a good place to buy lasers. There isn't any 445nm that's only 10mW as far as I know. 10mW is a small fraction of the power needed to burn stuff. Your eyes are ok, don't worry, just don't look at the dot while burning anything and don't look at it up close, put your goggles on for that. Just be careful of reflective surfaces like glass, mirrors, metal etc. if you shine it across the room you should be able to tell if the dot is too bright to look at, if there is any doubt then don't look at it. If you are still seeing after images for a few seconds then you are pressing your luck. :tsk:

Alan

Thanks, I saw the dot for a few second after shining it to the wall; Is that what you mean by after image. It is less severe to flash camera; it always happen to me when looking at the dot of my green laser.
 
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Thanks, I saw the dot for a few second after shining it to the wall; Is that what you mean by after image. It is less severe to flash camera; it always happen to me when looking at the dot of my green laser.

Yes if you see spots or lines after you turn the laser off, these should not last more than several seconds. Even then I wouldn't want that happening all the time, I suspect if you get close to 10 seconds or so of after image then your probably in the danger zone, over time it could do damage. I mostly avoid looking directly at the dot with my powerful lasers unless I am wearing glasses but I do like to look at the beam, but you must be sure no accident can happen. With some lasers even just the dot on the wall can be brighter than the sun.

Alan
 

moh17

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Yes if you see spots or lines after you turn the laser off, these should not last more than several seconds. Even then I wouldn't want that happening all the time, I suspect if you get close to 10 seconds or so of after image then your probably in the danger zone, over time it could do damage. I mostly avoid looking directly at the dot with my powerful lasers unless I am wearing glasses but I do like to look at the beam, but you must be sure no accident can happen. With some lasers even just the dot on the wall can be brighter than the sun.

Alan

Thanks, it lasts less than 10 sec; it was a bout 4 or 5 sec at maximum. The laser is probably a 200 mW or less. It is certain class 3B. I read that watching the spot of class 3b is harmless; Is that true ?. I will always wear safety glasses when using it. At first, I trusted the seller word, he told me do not buy laser goggles, its a low power laser.
 
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Thanks, it lasts less than 10 sec; it was a bout 4 or 5 sec at maximum. The laser is probably a 200 mW or less. It is certain class 3B. I read that watching the spot of class 3b is harmless; Is that true ?.

No, low power ones yes, but class 3B means less than 500mW, they aren't eye safe. It depends on what your doing.

Alan
 

moh17

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No, low power ones yes, but class 3B means less than 500mW, they aren't eye safe. It depends on what your doing.

Alan

My OD +7 goggle blocks the laser completely; you can't see the dot even in the dark. I found that my $ 5 laser goggles blocks most of the laser to a point that the beam is not bright; however, it is not good for my tested 7mW 405 nm. I do not know the reason. I guess because it blocks green lasers perfectly and 445 nm is closer to the green compared to the 405 nm wavelength.
 

moh17

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No, low power ones yes, but class 3B means less than 500mW, they aren't eye safe. It depends on what your doing.

Alan

See the response from the seller. I wonder if a kid purchased this laser. I always have bad luck with low power lasers. I guess I will put this laser in the microwave :eg: and throw it in trash.

hello
i am sorry, our packing guy tell me he ship 450nm 100mw laser to you
because the 10mw pen need technical guy to make who is very busy
i am sorry,
it dont need OD +7, this one is ok, please check
Aliexpress.com: ?????? ???????? ???? ??? 190 540nm 800 2000nm ????? / ????? ????? ???? ???? ?? ???????? ???? ?????????? ??????????? ?? Emma Technology Co., Ltd.
i am sorry again
because you need it very urgent,, we have no way, though we have at a loss
hope you understanding
 
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what do you mean by over spec ? ; I believe that 1mW will be a 5 mW which will be safe

Over-spec means the laser will output more then what it's being sold as. I.e if you buy a 5mW laser & it outputs 10mW's on an LPM, it's over-spec :beer:

-Alex
 

moh17

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Over-spec means the laser will output more then what it's being sold as. I.e if you buy a 5mW laser & it outputs 10mW's on an LPM, it's over-spec :beer:

-Alex
But if I bought a 1 mW and it outputs 5 mW. I will still be safe
 
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Don't double and triple post, you will get into trouble for that, use the edit button.

OD +7 isn't necessary unless you're building the Death Star.

IS OD + 4 good for 100 mW laser ?

Yes.

But if I bought a 1 mW and it outputs 5 mW. I will still be safe

Yes, no glasses ever needed for 5mW or less, just don't point it straight into your eye.

Alan
 




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