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Discontinuous Light Spectrum


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3 hours ago, Mehmet Saygın said:

The daylight continuous broad spectrum percevies as a white color to eye. How the fluorescent light make the same effect due to have narrow and discontinuous emission bands

spectral_responses2-housecraft-dot-ca.png

We have three types of colour sensitive cells in our retina. If different spectra trigger them all equally, we see them as equal.

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1 hour ago, studiot said:

Flourescent lights work by using the phosphor coating on the inside of the tube to emit the wnanted light.

 

Different phosphors give different spectra.

 

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So the color of the flourescent is depending the phosphor coating color. The actual color of flourescent light isn't white. The white phosphor coating gives the white color to flourescent light, is this the answer ?

18 minutes ago, Bender said:

We have three types of colour sensitive cells in our retina. If different spectra trigger them all equally, we see them as equal.

But this is the reason why I asker this question. The monochromatic light distribution of flourescent light is not similar to daylight. I mean there is a big light intensity increases in some narrow band,but the other regions have very low intensity values compared to the these regions.

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42 minutes ago, Mehmet Saygın said:

But this is the reason why I asker this question. The monochromatic light distribution of flourescent light is not similar to daylight. I mean there is a big light intensity increases in some narrow band,but the other regions have very low intensity values compared to the these regions.

Then what exactly de is your question? 

We sample only three values of a spectrum. More degrees of freedom are lost to us.

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41 minutes ago, Bender said:

Then what exactly de is your question? 

We sample only three values of a spectrum. More degrees of freedom are lost to us.

I mean according to Sir Isaac Newton, the white light is mixture of six monochromatic lights which are violet,blue,green,yellow,orange,yellow. These lights are available in daylight almost the same amount,but we can not to say this for flourescent light spectrum. Altough, how eye perceives the flourescent light as a white light ?

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Newton defined seven colours (you forgot indigo), but chose that number because seven is a special number. It is otherwise completely arbitrary.

We can only detect three colours (range of colour to be more correct), and perceive combinations of those as all the other colours. If we see yellow light, our red and green detectors get triggered, which our brain translates to "yellow" . When we simultaneously detect green and red light, the same detectors get triggered and our brain translates to "yellow". We cannot differentiate between those two situations.

The same happens with white light, but instead all three of our detectors get triggered. There are many ways to do this with different spectra.

We exploit the fact that we only have three detectors by putting only red, green and blue lights in any screen, as combinations of those can produce (almost) any colour we can perceive.

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10 hours ago, Mehmet Saygın said:

I mean according to Sir Isaac Newton, the white light is mixture of six monochromatic lights which are violet,blue,green,yellow,orange,yellow.

Seven. Red, Orange, Yellow, Green, Blue, Indigo, and Violet

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These lights are available in daylight almost the same amount,

Not really. There's a significant drop-off at the ends of the visible spectrum

5ac741fd38ac3_solarspectrum.jpg.a3c693e246779b4b2b3ad2c9476833ab.jpg

https://www.intechopen.com/books/advanced-catalytic-materials-photocatalysis-and-other-current-trends/first-transition-metal-oxocomplex-surface-modified-titanium-iv-oxide-for-solar-environmental-purific

 

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but we can not to say this for flourescent light spectrum. Altough, how eye perceives the flourescent light as a white light ?

Because the eye has different color receptors, as was explained.

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