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ArcticMyst Security by Avery

405nm lasesr ...NOT GOOD FOR BURNING ??!!!!






Joined
May 29, 2011
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Sigh. They were being sarcastic. 405nm Lasers are great for burning. Read through the thread a bit more.
Search through other threads. One thread is not reason to change your belief; get a second opinion; 405nm aren't very visible, but they're pretty good at burning.
 
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Joined
Mar 16, 2012
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319
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Sigh. They were being sarcastic. 405nm Lasers are great for burning. Read through the thread a bit more.
Search through other threads. One thread is not reason to change your belief; get a second opinion; 405nm aren't very visible, but they're pretty good at burning.

thanks for your reply !!!
yep...i have just read a whole thread about it and yea 405nm lasers area so far the best lasers for burning ( besides IR ) ...just wanted to make sure ^_^ :thanks:
i know that 405nm are not as much visible green ones but like you said they are great for PYROMANIACS !!! LIKE ME !! HEHEHE JK
TAKE CARE !!
 

ARG

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Sorry to inform you, but those "200mW" 405nm focusable lasers are usually PHR diodes putting out 40-80mW; sometimes 100mW if you're lucky.
 
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As far as brightness my eyes see 405nm very well, better than most, as I have exposed my family to this very test.
 
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Sorry to inform you, but those "200mW" 405nm focusable lasers are usually PHR diodes putting out 40-80mW; sometimes 100mW if you're lucky.

O really ??!!! Well let's see what it turns out ! Cause I'm doing an LPM test as soon as I get the laser !!:D
 
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My 445s burn cigarettes much better than my S06J does :p

Though I am comparing about 600mW of 405nm to near 3W of 445nm at about 3 feet away.

It all depends on the distance you hope to burn stuff. 405nm can burn for longer distance than 445nm because of the diode being single mode where most 445nm lasers are multimode.
 
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Joined
May 20, 2012
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Just did a quick "long distance" test. 405 550mw I can easily light a match at 25 feet.
445 2W would not. However I also couldn't get a descent dot at that distance.
Kind of spread out.
At a few feet no problem.
 

gillza

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Photons at 405nm are very energetic. The shorter the wavelength the more energy it will "carry" so when the photon at that wavelenght hits a molecule it disturbs chemical bonds and brakes them apart faster than photons with shorter wavelength. So at thus between the lasers with the same power the one with shorter wavelength will burn better.

Look at my signature for beam comparison if you are curious (445 and 405)
 
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I hope to get a few burn tests in on my days off soon.

I agree that wavelength has a direct effect on the burn power of a given laser but 405nm is quite close to 445nm. AFAIK, the main factor that allows most 405nm laser to compete with much higher powered 445nm lasers is beam specs. If one could hold a 9mm 445nm diode's beam to the same specs as a single mode S06J then there should be absolutely no contest. The reason 405s out burn 445s at range is because 445s have comparably horrible beam specs so their power gets spread out more.
 
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This absorption spectrum "rule" has been discussed before and should not be relied upon.

It's not the amount of energy carried in the individual photons that makes the difference. Whether those photons get absorbed by a particular material--as defined by the absorption spectrum--is what matters. For example, the thermopile sensors of laser power meters are coated with a surface that is supposed to absorb most wavelength equally; therefore, a simple reading of the absorbed power is sufficient to determine the power of the laser. A meter using a photodiode sensor, however, has a different absorption spectrum and therefore any meter must account for the wavelength in determining what power was actually measured.

The typical materials people burn with their lasers--organic materials--just happen to absorb light in the near-UV range better than longer wavelengths. That'll change if you try burning some other material, or if you add pigments to your material that change the absorption characteristics of your material. This is why people sharpie their matches or paper to make such materials burn better.
 




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