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FrozenGate by Avery

Newb alert: few questions






Guyfromhe said:
I can't see how wavelength would effect it...
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I always wondered. v=λ*f, where v=velocity, λ=wavelength and f frequency.
Also, Energy is given by E=h*f . in order to achieve high E you need high f since h is stable, so you need small λ in order to keep velocity the same. I doubt this is correct though.
 
People have mentioned that nobody has reported their laser not being sent due to customs confiscating it. Packages and usually xray scanned to see the contents, and a laser pointer probably wont be a red flag, unless it says CONTENT CONTAIN ILLEGALLY POWERFUL LASER. We'll see haha.
 
100mW of violet has fewer photons per second than 100mW of green, but violet photons carry more energy. Think of it as 2 burly men being able to lift as much as what 10 nerdy white kids could.
 
@Guyfromhe

So i was right ! Thanks Cyparagon and Silvershot for the explanation ! You both deserve a +1 rep
 
 
Cyparagon said:
100mW of violet has fewer photons per second than 100mW of green, but violet photons carry more energy. Think of it as 2 burly men being able to lift as much as what 10 nerdy white kids could.
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Then how can you measure a 100mW violet laser and a 100mW green laser on the same LPM? One of them would have to be wrong...

If a violet photon is carrying more energy than a green one it would lead me to believe that it must then be a higher energy rating thus not in fact the same power as the green laser. We aren't talking about power per photon, we are talking about Mill watts which is based on work preformed over a period of time (if you preform more work your wattage rating goes up)

So if both lasers are preforming the same amount of work and assuming the same absorption rate of both wavelengths the burning capability should be the same.
 
I will leave this to the experts !!! Guyfromhe 2 of LPF best members told you that 405nm burns better than 532nm why dont you believe it ?
 
This probably wont be my last buy, so I'm going to go with a tmart ones for $32 marked as 200 mw, assuming its around 50 - 100+ mw in reality. I'll buy the $30 from the link above later and compare. I want a green one because I decided I like how bright it is. Thanks for offering to build one, can you only do blue?
 
jimdt7 said:
I will leave this to the experts !!! Guyfromhe 2 of LPF best members told you that 405nm burns better than 532nm why dont you believe it ?
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No one has yet to explain how you can meter two different wavelengths at the same power on the same thermal meter if each laser is generating a different amount of heat...

In the given analogy "2 burly men being able to lift as much as what 10 nerdy white kids could." It would be more like measure how much a burly man can lift and measure how much a nerdy white kid can lift and then make them equal (same power) Sure there will be less burly men but they will preform the same amount of work. Because we are talking about a unit of work not energy per photon. I agree with you guys on that point.

I asked Lasersbee for his opinion since he knows everything, hopefully he will chip in.
 
@Laserbee

Depending on you !

@Guyfromhe

I had one 100mw 532 metered and one 405nm 98mw metered ! The 405nm could burn my skin but the 532 couldnt the 405 lighted matches in less than 2 seconds ! The 532 more than 5 !
 
I think cyparagon is saying "it takes more 532 to be same mW as 405. but once they are both "100mW" it's still 100mW." but even if not my answer below remains the same...

but when you read about 405nm being smaller than 532nm, on the hobby level it is irrelevant because we don't have the optics to utilze it.

so that being said, 100mW is 100mW. now another topic could be what wavelength is more easliy absorbed into the most commont things we like to burn/cut/ignite with our lasers.


michael.
 
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Guyfromhe said:
Sure there will be less burly men but they will preform the same amount of work.
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"work" in that case being analogous to (not equal to) "power," not burning capability


Guyfromhe said:
how you can meter two different wavelengths at the same power on the same thermal meter if each laser is generating a different amount of heat...
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It would give a readout of the sum of the two powers. What does this have to do with anything? I missed that part.

A violet laser does burn better than an equally powered green, but not because of the energy per photon. It is for two different reasons. 1) the dot can be focused smaller, both because of the lower wavelength, and the larger initial beam diameter. More importantly: 2) materials often absorb violet light better than green light.
 
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Im confused, the 41.99 laser has a focus so it can burn better, but the other one is not capable of burning because it cant focus?

A focus is always nice, but I also feel like the size of the 30 dollar one is better for hiding it around in your pocket.
 
chipdouglas said:
I think cyparagon is saying "it takes more 532 to be same mW as 405. but once they are both "100mW" it's still 100mW." but even if not my answer below remains the same...

but when you read about 405nm being smaller than 532nm, on the hobby level it is irrelevant because we don't have the optics to utilze it.

so that being said, 100mW is 100mW. now another topic could be what wavelength is more easliy absorbed into the most commont things we like to burn/cut/ignite with our lasers.


michael.
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That was the point I was trying to make that's like saying a top fuel dragster and a Honda Civic both driving at 50 MPH the dragster will get to the finish first because it has a bigger engine... The numbers are relative... I was not arguing the point of whether it took more photons of any wavelength to achieve a particular mW rating. I 100% agree on that point.

Absorption is another very good factor and very likely part of it (probably another reason green seems brighter - more things reflect it) I completely agree I am probably wrong on this point purple likely burns better due to better absorption.

Cyparagon said:
"work" in that case being analogous to (not equal to) "power," not burning capability
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But the power is what is doing the burning, just like the burly men would be doing the lifting... the "power X area" ratio is what causes the burn to happen.

Cyparagon said:
It would give a readout of the sum of the two powers. What does this have to do with anything? I missed that part.
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The point being made here is that a green laser will heat an object less than a purple laser with the same power. I am asking how you can measure a green laser and get the same value when you measure the purple laser (not at the same time) on the same meter if green for example heats the sensor by 20 degrees and the purple heats it by 25 how could they possibly have the same power reading? That's all I am getting at.

Cyparagon said:
A violet laser does burn better than an equally powered green, but not because of the energy per photon. It is for two different reasons. 1) the dot can be focused smaller, both because of the lower wavelength, and the larger initial beam diameter. More importantly: 2) materials often absorb violet light better than green light.
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Again I completely agree with the absorption thing I give you that, and maybe you could focus it better but LMPing the two devices if one is focused better would the power reading not be higher?

That is where I am getting lost...
 
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