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ArcticMyst Security by Avery

"Burning Power" unit of measurement please?

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The other variable is focus... I've heard members complaining that their
100mW Blu-Ray can't pop a balloon... while I have a 50mW Blu-Ray that
burns the wood on clothes pegs...:thinking:

@Meatball... I don't have any other ideas as of yet...;)


Jerry


Ok... so about focus. We could incorporate a dot size I suppose..

Dang, this solution was supposed to be a simple one.

Now we have all these factors to incorporate in not just a procedure, but a formula. We need to find an equation that relates wavelength-distance-optical power-dot size-time- whats next? The humidity of the room?
 





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I'm sticking with "If you want to know the output of your lasers, buy an LPM", personally ... And yes, if you're measuring a DPSS laser, factors such as ambient temperature, etc definitely do come into play so the number of variables that would need to be overcome almost negates the entire concept of a "simple" test.
 
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I'm sticking with "If you want to know the output of your lasers, buy an LPM", personally ... And yes, if you're measuring a DPSS laser, factors such as ambient temperature, etc definitely do come into play so the number of variables that would need to be overcome almost negates the entire concept of a "simple" test.


I'm not very interested in the power output of my lasers. It's just a theoretical light measurement that can't be directly applied to the laser's abilities. Like I said earlier, when someone says they have a 175mw green laser, that doesn't mean much to me since I don't know how much "work" it can apply to a target. I won't be able to compare it's abilities to somone's 200mw red. Anyone can say that their 200mw greenie is more powerful than a 200mw red, simply because we know that the green laser will have more energy density, more ability to "do work" on a target. What I'm looking to do, is somehow quantify a laser's ability to "do work". I want to know, just "how much" better, is that 200mw greenie over the red?

This isn't about power output just in case you misunderstood or something. LPMs are useless to me.

BTW, do you have that 8x Kryton up and going? :D
 

sbdwag

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Measuring energy

Seems to me that If you had a knows quality of opaque liquid in a say glass test tube you could measure a temperature change over a given period of time to determine the mw of light energy converted to heat. You would have to determine the amount of light energy reflected away as well as the ambient temperature inertia of the container along with the heat transfer properties of the liguid. If you could calibrate this you could determine very accurately from sample to sample

regards
sbdwag
 

YGG

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There are just so many variables in each situation. It's going to be hard to make a proper formula, if you can do that properly.
 
D

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One moment. This will just give the burning power trough black electrical tape. Brown matches for example, are easier to burn with red than with bluray!
 
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Seems to me that If you had a knows quality of opaque liquid in a say glass test tube you could measure a temperature change over a given period of time to determine the mw of light energy converted to heat. You would have to determine the amount of light energy reflected away as well as the ambient temperature inertia of the container along with the heat transfer properties of the liguid. If you could calibrate this you could determine very accurately from sample to sample

regards
sbdwag

That's what a thermal LPM does.... but a little faster...:)

What Meatball is looking for is a standard measuring stick to know which (let's say 200mW)
laser of different wavelengths burns a standard something (black tape) more aggressively...


Jerry
 
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One moment. This will just give the burning power trough black electrical tape. Brown matches for example, are easier to burn with red than with bluray!

Thats why black tape should be used, since its will absorb a huge majority of all wavelengths of visible light. Forget this brown match poo. A brown match will reflect more light than black electrical tape. It would be best to use something that absorbs the energy of each laser wavelength.


That's what a thermal LPM does.... but a little faster...:)

What Meatball is looking for is a standard measuring stick to know which (let's say 200mW)
laser of different wavelengths burns a standard something (black tape) more aggressively...


Jerry

Exactly!

Perhaps to measure how effectively a laser applies energy to a target, regardless of power output or wavelength. Guys wouldn't it be the ultimate to know not just the power of your own lasers, but to be able to measure and quantify their unique ability to burn? To compare each one of your own lasers regardless of color? Don't you want to know HOW much better one of your greens is, over your reds?
 
D

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Thats why black tape should be used, since its will absorb a huge majority of all wavelengths of visible light. Forget this brown match poo. A brown match will reflect more light than black electrical tape. It would be best to use something that absorbs the energy of each laser wavelength.




Exactly!

Perhaps to measure how effectively a laser applies energy to a target, regardless of power output or wavelength. Guys wouldn't it be the ultimate to know not just the power of your own lasers, but to be able to measure and quantify their unique ability to burn? To compare each one of your own lasers regardless of color? Don't you want to know HOW much better one of your greens is, over your reds?
The fact that you see it black means that it absorb all the visible wavelenghts. There could be 2 things that you see black one of them abosrbing UV and the other not.

Thats why you can't use this to test 405nm.
 
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What? Black doesn't absorb 405nm? Why would the tape burn so easily then?
 
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I like this idea, it's not very specific but we could use it for quick comparisons. The thing is that we'll end up using the power as the main indicator so the math function would turn out to be useless.
 
D

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What? Black doesn't absorb 405nm? Why would the tape burn so easily then?

I'm not saying black doesn't absorb UV, I'm saying that the fact that you see something black doesn't mean it abosrb UV.
 
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A good flat Black surface also absorbs invisible wavelengths...:cool:

Jerry
 
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Yes I could agree to the same thing, simply because 405nm burns electrical tape so well. I think its safe to say that it is mostly absorbed.
 
D

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and how can you difference those than the black which doesn't? Again, this is only going to give you an idea on how fast does a laser cut electrical tape.

Brown matches for example, cannot be ignited with bluray but easy with red.
 
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and how can you difference those than the black which doesn't? Again, this is only going to give you an idea on how fast does a laser cut electrical tape.

Brown matches for example, cannot be ignited with bluray but easy with red.

Thats why we would use black electrical tape. Its black because it is awesome at absorbing the light we see. We CAN see 405nm light. When that energy is absorbed, it is converted into heat, which does work on the chemical bonds holding that tape together.

Brown matches don't work well simply cause they apparently don't absorb enough 405nm for enough work to be done from the energy applied.

It think its apparent enough, that 405nm light is absorbed just like red light and all the wavelengths in between.
 




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