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A wavelengh quiz!!

oikos

oikos

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okay! no open-book and no Googling or other cheating allowed!


Q: what is the wavelength in nm of the 3 colors of traffic lights (red, yellow, green)


the person who get the correct number for ALL 3 colors get +rep :yh:

NO CHEATING ALLOWED NO CHEATING ALLOWED NO CHEATING ALLOWED
 





It varies allot from traffic light to traffic light, but my answer is 624nm red, 585nm yellow, 525nm green (sometimes as low as 505nm). Really there is no correct answer IMO. :)
 
This would be a cool quiz, but I have seen traffic lights that are very different colors. They are not always the same.

Some yellows are more yellow, while the majority around here are more amber. I have also seen several green lights in one area that were blue-ish.

Also, they will not be perfectly monochromatic. So an exact answer will not be possible.
 
The eye picks up some combinations better than monochrome. For example people see the red better if a little blue is added. There were some experiments (I don't know how well adopted the are) where some traffic lights have a blue reflective ring or blue filter lens around the red filter.

Also, any older lights with the white light behind a lens will be different than the newer LED based lights

It's never simple anymore, now is it?

Peace,
dave
 
umm... the traffic lights near my house are LED ones.... yea dave... it's not that simple as i thought :( ookay +/- 5 nm difference allowed now
 
FireMyLaser said:
It varies allot from traffic light to traffic light, but my answer is 624nm red, 585nm yellow, 525nm green (sometimes as low as 505nm). Really there is no correct answer IMO. :)
Click to expand...

umm... you're sooooooooooooo close!
 
Hehe did I get any of them right? The red may be a little higher, 635nm-ish. The yellow maybe 590nm. I'm happy with the green at 525nm OR 505nm.
 
For LED traffic lights im gonna go out on a limb here:

Red - 626nm AlInGaP
Yellow/Amber - 590nm AlInGaP
Green (BlueGreen) - 505nm InGaN
 
oikos said:
ummm..... 525nm OR 505nm what's your FINAL ANSWER??
Click to expand...

7!

No, but I find ~525nm looking to be more common here, though I'm only guessing it to be 525nm. But I know 505nm when I see it so I'm gonna say 505..?
 
aryntha said:
For LED traffic lights im gonna go out on a limb here:

Red - 626nm AlInGaP
Yellow/Amber - 590nm AlInGaP
Green (BlueGreen) - 505nm InGaN
Click to expand...

GOT IT! my answer:

625±5
590±5
505±2

p.s: soo sorry FireMyLaser... your answer was a little broad! but you ere close thou :o
 
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