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ArcticMyst Security by Avery

Question about 405nm

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Oct 5, 2009
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I bought a 5mw 405nm laser. I cannot see the beam at all and the dot is surrounded by a kind of dark purple from about a 10 foot distance. I can't see the dot at all when i shine it about 30-50 feet out in the dark. The dot almost looks white. Is this what i should expect from a 5mw 405nm laser? Do higher mw violet lasers have a visible beam and is there a clear dot instead of one thats blurry? And yes I tried cleaning the lens.
 





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Lol welcome to the forum and ur new hobby! at 5mw your not going to get a visible beam! At around 80mw my PHR (type of blu-ray diode) only gave a faint beam, without smoke/fog you will not see it. As for the dot could you please upload an image just so we can see whats going wrong?

-Adrian
 
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lol thanks. I mean the dot gets really wide when its not even too far away. And also what exactly is a blueray is it the same as 405nm? And what is 4x, 6x, ect... stand for?
 
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Yes, 405 nanometers is the wavelength of a bluray laser. 4x and 6x are burning speeds of bluray burner drives, as in a 6x burner will write a disc six times faster than a single speed drive.
All the things you described are perfectly normal. Read this for more info: http://laserpointerforums.com/f38/strange-things-about-blu-ray-405nm-20042.html

And while you're at it you may want to read: http://laserpointerforums.com/f36/basic-faqs-read-before-posting-38275.html

All your questions have been answered thousands of times already, have a look around and read up a bit, I guarantee you'll learn countless interesting things.
 
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The dot of any 405nm laser is going to look blurry over even just small distances because our eyes have trouble perceiving the color. To see the beam make sure you are in a very dark area.
 
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Try pointing the laser far away, and then walking up to the dot. You will notice that it's not blurry at all. As Styropyro said, our eyes have trouble "seeing" 405nm.
 
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If I got a higher mw blue ray would i be able to see the dot further away or will it still be blurry?
 
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You will be able to see it at more of a distance but it won't won't be near as effective as even a 5mW green.
 
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It would be much easier for you to read, rather than post. Your questions have already been answered, just read.

This reminds me of my work, I fix people's computers and often I need to tutor them on things.. All too often, as I'm explaining something, the person keeps interrupting me, asking the exact thing that I'm trying to tell them... "So, to defrag your hard drive, you'll need to click here, then ---" "HOW DO I DEFRAG MY HARD DRIVE" "well sir, as I was saying you click here, then ---" "BUT HOW DO I DEFRAG IT"

You learn a lot more by listening than talking.
 
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It would be much easier for you to read, rather than post. Your questions have already been answered, just read.

This reminds me of my work, I fix people's computers and often I need to tutor them on things.. All too often, as I'm explaining something, the person keeps interrupting me, asking the exact thing that I'm trying to tell them... "So, to defrag your hard drive, you'll need to click here, then ---" "HOW DO I DEFRAG MY HARD DRIVE" "well sir, as I was saying you click here, then ---" "BUT HOW DO I DEFRAG IT"

You learn a lot more by listening than talking.

Too true! light diffusses at the rate of 1/d^2 (d being distance) meaning that the futher away you get from the source the larger the spot will be! a lens keeps it tighter and allows you to get smaller "dots" at further distances... if that made sense. does your laser have a focusable apeture? im guessing not.. if not its probably going to stay that way even after cleaning your lens :(

Maybe I should just buy a blue laser. They are more visible right?

A "blue" laser is a very expensive bit of equipment! The only alternative is Blu-ray which is sort of a blu-violet color! but yes blue is slightly more visible then blu-ray... why dont you just get a green laser? look at the beam of the laser in my sig (bottom of this post, it says review here!)

hope that helped! -Adrian
 
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