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Prove my science teacher wrong!

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cool make a review when you get it...
 

Cyparagon

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I thought the higher power density of 405nm diodes was primarily due to their smaller die size. Now I am not confident in that, but I am confident in my previous post.
I'm pretty sure sure they are the same size - something like 1x2 microns. Violet can be focused smaller because it has smaller diffraction limitation. Here's an article that explains some of it.

tthudium, you have the wrong approach to this problem. "The purpose of an argument should not be victory, but progress."
 
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Trevor

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She explained it poorly, but she is correct.

The shorter a laser's wavelength, the more energetic the photons. This is independent of power.

Also, what Cyparagon said... :thinking:

Trevor
 

tthudium

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I like your quote "the purpose of an argument shoulf not be victory, but progress" quote cyparagon. ^_^
 

Lase

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The shorter wavelengths allow the photons to rapidly excite a target area, which leads to faster transfer of energy.

Take a 660 laser and a 405 @ ~300mW:
- The 405 will be able to impart it's energy into the target faster and burn it.
- The 660 will still be able to burn the target but will take a longer amount of time to do so.

Lase
 
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Cyparagon

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The shorter wavelengths allow the photons to rapidly excite a target area, which leads to faster transfer of energy.
That would mean microwave ovens are impossible and X-rays would cause you to burst into flames ;)
 

Lase

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That would mean microwave ovens are impossible and X-rays would cause you to burst into flames ;)
Im recalling that from yr 9 science... So about 10 years ago, must've gotten mixed up.

But its something like that i'm pretty sure.

Lase
 
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DrSid

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True, blue photons do carry more energy, but that also means it's harder to produce them. 200mW is 200mW, be it blue, green, red or microwave. The power is the same. Count of the photons to get that power is not the same.
So simply do not compare colors of lasers, just compare their power. Then the more powerful is well .. more powerful.
 
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I think red cars are the fastest. Much faster than blue or green cars. Although yellow cars are really fast too, maybe almost as fast as red cars. Purple cars are just stupid and slow.
 
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"She said that green lasers were more powerful than red, and purple were (more) powerful than green."

I think that the original statement isn't defined properly.
Get a different or better definition for her use of "powerful".
My biggest problem with teachers way back when going to school had to do with the single mindedness of some. They only think of things in their own way and do not allow for possible misinterpretation by others.
I have been told that I am a great teacher as I can always state a point or thought in many different ways allowing for everyone to understand. (I find it to be a good mental exercise personally. Keeps your thought processes limber, so to speak.)
The electrical definition of power is actually quite limited. 500 mw is 500 mw no matter what wavelength.
However, as explained previously here, the energy state of the photons of different wavelengths will differ greatly.
So depending on how the original term "power" was being intended is the real question.
Or was that a paraphrase of a discussion with the wrong terminology being posted by you ?
:thinking:
 

DrSid

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If there was 500mW green laser on the table and 200mW red, then indeed, the green laser was more powerful then the red ! Problem solved.
 




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