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Translating Wavelengths to Colors!

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Hey Everyone!


When I first started shopping for lasers, I wasn't sure how each wavelength, (also known as "nm" or "nanometre") translated to it's respective color, so I thought I'd share this image with the member-base here, so you can see not only what each wavelength (numbers at the bottom) translates to in color, but also how the human eye perceives that wavelength. So for example, 525nm - 575nm, according to this graph, are the most visible with the minimal amount of wattage.







As an additional bit of information, 556nm lasers are considered the most visible beam, and require very little wattage to produce a visible beam. A green/yellow laser is said to be 5 TIMES more visible than a blue beam. Therefore, a 500mW green laser, is the equivalent in visibility of a 2500mW blue laser! So, if visibility is what you're after rather than "burning power", a green/yellow laser is the one for you.

Here's an example of the beautiful "556nm" (Yellow-Looking) wavelength, next to a "532nm" (Green-Looking) wavelength.





(IMAGE BY LPF MEMBER 'rhd')




I hope this little bit of information helps some out. Best of luck with your Death Rays. :evil: :beer:

(I apologize, as I'm sure this has been mentioned in other posts, but nothing wrong with 'BUMP'ing this information back up, so new members have a better chance of finding it)​
 
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Hap

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Everything looks great :)

But there is one mistake, currently 556nm lasers have the most visible beam.

With a light adapted eye peak wavelength is 555nm, on the other hand a dark adapted eye the peak wavelength is now 507nm :beer:
 
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Everything looks great :)

But there is one mistake, currently 556nm lasers have the most visible beam.

With a light adapted eye peak wavelength is 555nm, on the other hand a dark adapted eye the peak wavelength is now 507nm :beer:
Edited the paragraph to reflect that info. Thanks. :beer:
 

Hap

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Edited the paragraph to reflect that info. Thanks. :beer:
Great!

Extra: You are one of the best newcomers I have seen since I joined LPF, you look like you really want to learn and are willing to take criticism so you can improve yourself.

Earned my respect already :D
 
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Great!

Extra: You are one of the best newcomers I have seen since I joined LPF, you look like you really want to learn and are willing to take criticism so you can improve yourself.

Earned my respect already :D
Haha, well, that's the goal. Learn what I can, share what I know, and enjoy a new hobby along the way. ;)
 

Hap

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Though after re-reading I would maybe change the part where "they are used for star-gazing".

556nm units are very expensive and are not available in high powers unless you have $xx,xxx :)
 

Hap

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False. Even a 50mW 532nm pointer will be substantially brighter than than rhd's 20mW unit.
Yes of course it will.

Im stating that overall per mW 556nm is brighter then 532nm(if the eye is light-adapted) :)
 

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Are you talking about relative visibility? The eye has a different peak visibility in day/night. The scotopic (low light conditions) sensivity is around 500nm, the photopic vision (well-it conditions) is around 550nm. There are different charts with deviant values around. This here shows scotpic and photopic curves:

 

Hap

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Are you talking about relative visibility? The eye has a different peak visibility in day/night. The scotopic (low light conditions) sensivity is around 500nm, the photopic vision (well-it conditions) is around 550nm. There are different charts with deviant values around. This here shows scotpic and photopic curves:

Yes exactly!

555nm is peak brightness for a light-adapted eye, which in turn makes 556nm brighter then a 532nm.

Edit: The "wavelength spectrum" chart you posted insn't 100% accurate :)

550nm is not green, this is a green/yellow mix. Red dosen't start at 700nm it starts at 650nm.
 
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DJNY

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The graphs on the internet contain different (peak) values. Maybe they had a difference definition of "low-light/well-ligth conditions" - would make sense.


550nm is not green, this is a green/yellow mix. Red dosen't start at 700nm it starts at 650nm.
Who is saying that? You? :thinking:
You should be careful with such statements :)

Definition from WIKIPEDIA

Red is the color of blood, rubies and strawberries. It is the color of the wavelength of light from approximately 620–740 nm on the electromagnetic spectrum. Next to orange at the end of the visible spectrum, red is commonly associated with danger, sacrifice, passion, fire, beauty, blood, anger, Christmas, socialism, communism, and in China and many other cultures, with happiness.
 

Hap

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Well most people would consider 700nm to be IR while others consider it dark-red.

I personally believe 650nm is red and 700nm is a slightly darker-red, this is just the way I view it. All depends on perspective.


Many Electronic Spectrums from numerous "University Websites" show Red to start at/around 650nm and IR starting at about 700nm.
 
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DJNY

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^ Accidentaly gave you a +rep, but hope you consider the message next to it for your future posts
 
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Hap

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^ Accidentaly gave you a +rep, but hope you consider the message next to it for your future posts
Yea haha I did notice it. I will consider it, just trying to help the new guy out. Didn't try and sound like I knew everything since I know I don't, im very new in this hobby :)
 

DJNY

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Yea haha I did notice it. I will consider it, just trying to help the new guy out. Didn't try and sound like I knew everything since I know I don't, im very new in this hobby :)
We´ll see! Otherwise, next time -rep :)

It´s good to see young motivated people fascinated about lasers and who also know how to handle them without harming others or themselves.
But as Cyp and some others also tried to tell you > SLOOOOW DOWN and think about your posts before approving them. You don´t have to reply to every single thread you´re interested in. You can also use google to confirm your statements or modify them with correct/additional info before posting them. I do this as well from time2time.



Back to the topic :beer:
 
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