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FrozenGate by Avery

Strange (maybe not?) thing when burning with red.

AJ_Dual

AJ_Dual

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I've noticed sometimes when I get the focus just right with my 200mW O-Like "new style" Dilda I can get a very intense blue/white little flare right at the point of burning.

I know it's not an overload of my eyes or anything (stupid/dangerous) like that, because I can see the little flare even through my blue laser goggles.

Is this just a perfect spot of incandescent vapor? Or just a little spot where it's so bright it just looks "white" even through OD+5 goggles?
 





It is well known. Somebody may come by to explain the science, but it is normal.

Peace,
dave
 
You can also see very intense yellow dot flare with IR laser burning, and it's very easily visible because laser does not "get in the way". Sometimes that little yellow spot goes white so bad that it hurts to look at it, if you get the right material to burn with high enough power and well enough collimated.

I believe it's the little particles of smoke that just evaporated from material you are burning , caught right in the very focal point of the laser and they get superheated. Blue light with red laser can be optical illusion or something to that effect.

Would be really interesting to see what's actually going on. I remember myself posting exact same question in my starting days on this forum.
 
this happens with any color laser:) works with my PHR, red, and used to work with my IR, before it died. i think it is just a very small spot where the material gets superheated, like Eudaimonium said.
 
unsustainable combustion would be my guess. Focal point ignites the vaporized material that hasn't been completely carbonized.
 
I actually video documented it. You can clearly see the white flashes. With a 445nm, the flashes are PINK.

 
Whe the energy density reaches some point there are no combustion, just disintegration of material, no little flames, the energy density a the pinpoint of the beam is so high that the materials literally sublimates even the possible ashes there could be. That pinpoint could reach easily +1000 Celsius (if beam is absorbed by the material) At some powers surrounding material around the pinpoint could reach enough temperature and Oxigen to start normal combustion; but the pinpoint simply sublimates material. Some time ago, I found a very very little fly on white piece of paper, to have fun I decided to toast it with a 200mw red I had around. Once finished there wasn't even ashes! Just that horrendous smell... some of you for sure know what I'm talking about.
 
I've been noticing this effect with my own 200mW reds for a long time now, and documented it in some of my YouTube videos. I always referred to it as "white flashes due to vaporization" because I didn't really know what else to call it. I've found that with those 200mW reds, it's really just a neat effect to watch with goggles, but with the high power 445nm blues operating near/at/over a watt, it becomes a real problem because the extra frequencies of light will go right through at least my goggles and make the dot very hard to look at. I've also found that it can become a sort of standing wave effect with some materials, like cardboard and paper, where if you carefully aim at the "hot coal" that the laser dot can create as it burns the material, the coal will grow and grow in brightness until it is painful to watch. I'm going to experiment with additional filtering over or behind the goggle lenses in order to reduce this effect and make burning more workable and also eye safe, since staring at such a bright pinpoint of mixed frequency light surely would be potentially damaging like staring at the laser dot itself, just maybe not AS damaging. Whatever the case, it's a trully fascinating effect, makes me think of movies like Spider Man II or Chain Reaction where a point of high energy excitation takes place... and then Morgan Freeman shows up and destroys my duplex home in order to bury my discovery, while I go on the run with my blue laser. That would be kinda cool. ;)

- NR

PS: I of course refuse to admit that I have any idea what odor magonegro is referring to.
 
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I have the same effect....I notice it a lot when I am melting plastic. I get that perfect focus and the dot starts to flash white....I think of it as a "sweet spot" cuz everything just melts the best there. Glad to hear it isn't something bizarre tho
 
Chip weevils are attracted to high density coherent light. Such is the source of their destruction. You can be assured that this white, flickering ball can only be good for the longevity of your solid-state light-emitting electronics.
 
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