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Prove my science teacher wrong!

tthudium

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Ok so me and my science teacher were talking about a science Olympiad event; optics. She said that green lasers were more powerful than red, and purple were powerful than green. She explained this because purple laser's wavelengths were very "hyper" and red was slower. I tried to explain that it depends on how much power they had and how many mws they had... And the wavelength determined the color.

Was I right or was she?
 

cvbcbcmv

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Ok so me and my science teacher were talking about a science Olympiad event; optics. She said that green lasers were more powerful than red, and purple were powerful than green. She explained this because purple laser's wavelengths were very "hyper" and red was slower. I tried to explain that it depends on how much power they had and how many mws they had... And the wavelength determined the color.

Was I right or was she?
You're correct. Science teachers have some of the least knowledge of science of anyone I have every known. She's completely wrong, I'm mobile so I can't type out the scientific explanation, I'm sure someone will be on it soon. 405nm makes the most minimal difference as possibly burning better due to it's wavelength, but is not considered more powerful in any form.
 
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LaZeRz

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Not more powerful, but can be absorbed by a wider range of objects. Try burning white paper with a 660, then a 405. The 405 wins.
 
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The visibility of a laser is dependent on wavelength and power, green is indeed most visible but only because the human eye has peak sensitivity to 555nm, so we see 532nm brightest.
 

cvbcbcmv

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But while something is brighter, it is by no means more powerful. my 500mW green is brighter than my 1W blue, but the blue is a hell of a lot more powerful.
 
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Right, because the wavelength sensitivity of our eyes. :) It is interesting to me that some animals see different wavelengths as brightest.
 

HaloBlu

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When talking about single photons 405nm is more energetic.
Since you mention "hyper" perhaps she was referring to that.
 

cvbcbcmv

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Yeah, that is pretty cool about animals.


hey, a bit off topic, but, anyone buy one of those 250mW 635nm reds from o-like, I bought mine about a month ago and was told they were going to be rebuilt like 2 weeks ago. I didn't spend 25 dollar shipping for nothing.
 
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Food for thought: Planck relation
The Planck constant was first described as the proportionality constant between the energy (E) of a photon and the frequency of its associated electromagnetic wave (ν). This relation between the energy and frequency is called the Planck relation or the Planck–Einstein equation:
E=hv
As we all know, wavelength is inversely proportional to frequency. One "blue" photon has a greater energy than one "red" photon.
 
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It's obvious the winner is 405 :D Why because of the same reason they started using it in CD writers in the first place.
it has a narrower beam than a 532nm or 650nm or a 880nm laser so it's power in more dense cuz it in a smaller area.
this is how they get so much more info on a BluRay disc because it's physicly a smaller beam.
Think about it like this if you have 100 watts of beam power in a 1 inch wide beam and it can only cut
through 6mm of plate steel then 100watts in a 1/2 inch wide beam can cut through 24mm of plate steel :D

It's a beam density thing and not a nm thing.
some one check me here if I'm wrong.

hope that helps...
 
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It's obvious the winner is 405 :D Why because of the same reason they started using it in CD writers in the first place.
it has a narrower beam than a 532nm or 650nm or a 880nm laser so it's power in more dense cuz it in a smaller area.
this is how they get so much more info on a BluRay disc because it's physicly a smaller beam.
Think about it like this if you have 100 watts of beam power in a 1 inch wide beam and it can only cut
through 6mm of plate steel then 100watts in a 1/2 inch wide beam can cut through 24mm of plate steel :D

It's a beam density thing and not a nm thing.
some one check me here if I'm wrong.

hope that helps...
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.
 
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Yeah, that is pretty cool about animals.


hey, a bit off topic, but, anyone buy one of those 250mW 635nm reds from o-like, I bought mine about a month ago and was told they were going to be rebuilt like 2 weeks ago. I didn't spend 25 dollar shipping for nothing.
im confused did it arrive not working? and you sent it back and they are supposed to fix it?
 




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