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If a Green 532 is the brightest then what's second brightest?

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Capitol

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I already have a green 532 laser and I understand it's the brightest color of laser available.
If the 532 is the brightest then what's the next level down in brightness?
 





Capitol said:
I already have a green 532 laser and I understand it's the brightest color of laser available.
If the 532 is the brightest then what's the next level down in brightness?
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trussmonkey25 said:
531 nm
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HaHa, that is the correct answer except that it doesn't exist as far as I know. The answer your probably looking for is 520nm. I have one and even at only 82mW it still has a visible beam.

Alan
 
Pi R Squared said:
HaHa, that is the correct answer except that it doesn't exist as far as I know. The answer your probably looking for is 520nm. I have one and even at only 82mW it still has a visible beam.

Alan
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There is a paper about a diode pumped self frequency-doubling Nd:GAB that lases at 531nm but I also think 520nm is the answer he wants. :D
 
Well, I'm sure I remember there being 545nm and even 556nm DPSS lasers, no? But those aren't very common. 561nm DPSS is not ultra rare like the others, so that would be the closest that's somewhat commonly available. So really, 532 is sort of the second. Maybe even third, depends on your definition of common.
 
I usually use this calculator made by RHD to compare the brightness of different wavelengths with eachother. I didn't find it as accurate as I thought it would be when comparing my own 1W 405nm with a 50mW 532nm, but that could be because not everyone is as sensitive for a certain color than others.
 
Gabe said:
So really, 532 is sort of the second. Maybe even third, depends on your definition of common.
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A lot of people seem to be forgetting that perceived brightness depends on wavelength AND power.

A 3mW 561nm pointer will only have 13% more luminosity (therefore <4% increase in perceived brightness) compared with a 3mW 532nm pointer. This is negligible - you're not even going to see a 4% difference.

A 4mW 532nm pointer is still brighter han a 3mW 561nm pointer. 532 DPSS is available in much higher powers for much lower prices than 561 DPSS.

Going with "the spirit" of the question, 520nm would subjectively be the proper answer.
 
Actually the peak brightness for beams (using the CIE 1978 model corrected for Rayleigh scattering) is closer to 540nm. Therefore, the brightest commonly available laser beam is from a 543nm HeNe. Then again the difference is so small anything from 520nm to 561nm should look about the same brightness, and anything from 500nm to 600nm should look pretty bright.

Edit: but of course Cyp is correct and the NDB7475 is probably the brightest single diode around.
 
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Cyparagon said:
Source? All the CIE 1978 plots I've seen peak at 555.
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He meant beam brightness. Because shorter wavelengths get scattered more in the air, a shorter wavelength is going to loose more power through beam scattering, resulting in a brighter beam. I'm sure you knew this I just wanted to clarify.
 
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Cyparagon said:
A lot of people seem to be forgetting that perceived brightness depends on wavelength AND power.

A 3mW 561nm pointer will only have 13% more luminosity (therefore <4% increase in perceived brightness) compared with a 3mW 532nm pointer. This is negligible - you're not even going to see a 4% difference.

A 4mW 532nm pointer is still brighter han a 3mW 561nm pointer. 532 DPSS is available in much higher powers for much lower prices than 561 DPSS.

Going with "the spirit" of the question, 520nm would subjectively be the proper answer.
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I was assuming, I think along with everyone here, that he meant at the same power. I also imagined that the difference between 561 and 532's brightness is more than negligible, I thought I remembered a few people saying their 20mW 561nm were as bright or brighter than a 30mW 532. 'Course, I don't think they metered each one. I see how easily I could be wrong, a whole lotta 'I think' s and 'I assume' s in there. But, in my mind, every nanometer closer to the peak sensitivity counts, and 561 is not a crazy rare nearly unheard-of wavelength like 545nm or 556nm. So I felt like 561 is the brightest somewhat public wavelength, then 532nm, THEN 520nm. Then 515, 589, and so on.
EDIT: You're right, I got mixed up. Misread the question. Yes, 520 is the next step down in brightness. BUT, there's also a next step up in brightness, which is 561. I thought he was asking for the second brightest, my bad.
 
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Cyparagon said:
Source? All the CIE 1978 plots I've seen peak at 555.
Click to expand...

micheal rosen said:
He meant beam brightness. Because shorter wavelengths get scattered more in the air, a shorter wavelength is going to loose more power through beam scattering, resulting in a brighter beam. I'm sure you knew this I just wanted to clarify.
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Yes, that's what I meant. Here's a chart of the normalized curves, including one corrected for scattering (1/λ^4):

Untitled.jpg
 
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