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ArcticMyst Security by Avery

Dot temp

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just curious if anyone has aimed there bluray at a thermal couple to measure the heat generated? Wow that dot gets hot on the finger!! Maybe I'll try it... Hmmm maybe a mw=aprox temp chart would be cool?
 





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Well it really depends on the surface's absorbance.So you'll probably not gonna get an accurate reading of what temperature your finger reaches , from reading the thermal couple.
 
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I can't get mine to hurt me, it only feels a little warm! It's measured at 118mW. (Then again, I am really afraid of focusing it at close range without goggles. I'll just wait a few days.)

I thought I had it at the focus point, but I was using my breath to visualize the beam while focusing it. Not too accurate. Oh well. I'll figure this out...

-Mark
 

daguin

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rocketparrotlet said:
I can't get mine to hurt me, it only feels a little warm!  It's measured at 118mW. (Then again, I am really afraid of focusing it at close range without goggles.  I'll just wait a few days.)
I thought I had it at the focus point, but I was using my breath to visualize the beam while focusing it.  Not too accurate.  Oh well.  I'll figure this out...
-Mark

You're not getting it focused. If it is actually putting out 118mW it WILL burn your skin (in a very short time).

Peace,
dave
 
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I was thinking, is it possible to pulse a laser at a rate at which the temperature would be hot enough to kill germs or a disease but leave regular tissue untouched.

I tried using my dx200 on this ginger kids arm, but it didn't do anything except make his arm glow red.( the light dissipated in his arm to quickly)


I would like to know how much heat is produced when properly focused on say black paper.
 
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Mine burns wood pretty good, wish I had a infra red thermometer. I would really like to measure the surface temp on the burning wood.
 
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daguin said:
[quote author=rocketparrotlet link=1226631087/0#3 date=1226709307]I can't get mine to hurt me, it only feels a little warm!  It's measured at 118mW. (Then again, I am really afraid of focusing it at close range without goggles.  I'll just wait a few days.)
I thought I had it at the focus point, but I was using my breath to visualize the beam while focusing it.  Not too accurate.  Oh well.  I'll figure this out...
-Mark

You're not getting it focused.  If it is actually putting out 118mW it WILL burn your skin (in a very short time).

Peace,
dave[/quote]

118mW, as measured by jayrob. As I said before, though, I don't want to look at it so close, so it probably wasn't focused right.

-Mark
 

daguin

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rocketparrotlet said:
118mW, as measured by jayrob.  As I said before, though, I don't want to look at it so close, so it probably wasn't focused right.
-Mark


Definitely, then. You can focus it without danger by shining it on a non-reflective dark (brown or black?) surface. With my 110mW, I just focus the beam until it smokes the front of my (distressed) dark brown wooden desk drawer ;) It will burn my arm when focused that way.

Peace,
dave
 

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laserwanabe said:
I was thinking, is it possible to pulse a laser at a rate at which the temperature would be hot enough to kill germs or a disease but leave regular tissue untouched.

I tried using my dx200 on this ginger kids arm, but it didn't do anything except make his arm glow red.( the light dissipated in his arm to quickly)


I would like to know how much heat is produced when properly focused on say black paper.
Yea , I noticed that you have to have a pretty dark skin tone to be burned by a red laser.Blu-ray on the other hand burns white paper, so it will burn white skin pretty well too.It also gives you cancer.
As for killing germs and disease, lasers may kill or may stimulate growth of certain bacteria while having all sorts of effects on tissue, depending on wavelength , power , and exposure time of course, so you would have to do a really in-depth study to tell for sure.Though I bet the information is out there already. :p

And as for how much heat is produced on black paper all you need to know is the absorbance ratio.Heat is basicaly energy.So if black paper absorbs 70% and reflects 30% of a 300mW laser then 210mJ are produced each second, and dissipated depending on the papers properties , ambient temperature, air flow, etc.You can then convert that to calories if you like. :p
 
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laserwanabe said:
I was thinking, is it possible to pulse a laser at a rate at which the temperature would be hot enough to kill germs or a disease but leave regular tissue untouched.

I tried using my dx200 on this ginger kids arm, but it didn't do anything except make his arm glow red.( the light dissipated in his arm to quickly)


I would like to know how much heat is produced when properly focused on say black paper.
UV light kills bacteria ;)

Ted
 

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Montana64 said:
[quote author=laserwanabe link=1226631087/0#5 date=1226710280]I was thinking, is it possible to pulse a laser at a rate at which the temperature would be hot enough to kill germs or a disease but leave regular tissue untouched.

I tried using my dx200 on this ginger kids arm, but it didn't do anything except make his arm glow red.( the light dissipated in his arm to quickly)


I would like to know how much heat is produced when properly focused on say black paper.
UV light kills bacteria  ;)

Ted
[/quote]

And people. ::)


Well, it's not as simple as that.But I think the general consensus is that 405nm isn't UV, so we don't have UV lasers to play with.
The water purifying and germ killing thingies that use UV are of a very short wavelength which is extremely dangerous to us too.If we had 100mW pointers of that wavelength , those would be very dangerous, and we would all probably get cancer. :p
 
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I think we will get UV pointers one day, i know the HeCd lasers are UV and there amazing looking. I think 405 might be pretty dangerous, it pretty close to UV it burns skin easily and we don't really know that much about it.

We don't really have the resources to research this 405nm wave length.
 

diachi

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laserwanabe said:
I think we will get UV pointers one day, i know the HeCd lasers are UV and there amazing looking. I think 405 might be pretty dangerous, it pretty close to UV it burns skin easily and we don't really know that much about it.

We don't really have the resources to research this 405nm wave length.


405nm isn't UV, and cannot give you skin cancer. Only UVB and UVC can do that.

-Adam
 
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Diachi said:
[quote author=laserwanabe link=1226631087/0#12 date=1226765087]I think we will get UV pointers one day, i know the HeCd lasers are UV and there amazing looking. I think 405 might be pretty dangerous, it pretty close to UV it burns skin easily and we don't really know that much about it.  

We don't really have the resources to research this 405nm wave length.


405nm isn't UV, and cannot give you skin cancer. Only UVB and UVC can do that.

-Adam[/quote]
I didn't say anything about Cancer... I said it is "Dangerous" which it is because it burns skin easy. And i know 405 isn't UV i said it is pretty close to UV.
 





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