Colors are the result of electromagnetic waves occurring in a specific “wavyness” as this image shows 
Seen another way, the visible spectrum is the range of wavyness (wavelengths) that human eyes can see. Notice how violet is way off on the edge.
But why do I say you can’t show violet on a screen? We can clearly show purple. Isn’t violet a shade of purple? Here’s where what you thought you knew gets turned upside down.
Remember how we can make colors from other colors.
Red and yellow combine to make orange and so on.
Purple is a mix of red and blue.
Red and yellow combine to make orange and so on.
Purple is a mix of red and blue.
Now look at the spectrum again.
We see how orange is produced when we go from red to yellow.
And green is produced when we go from yellow to blue.
But something is wrong. We never actually go from blue to red. So what’s that purple looking color doing at th end?
We see how orange is produced when we go from red to yellow.
And green is produced when we go from yellow to blue.
But something is wrong. We never actually go from blue to red. So what’s that purple looking color doing at th end?
Well red is all the way at the other end, doesn’t blue transition back to red to produce purple?
As this diagram shows, rainbows actually keep going on both ends producing astronomically more colors than we are able to see.
As this diagram shows, rainbows actually keep going on both ends producing astronomically more colors than we are able to see.
The human eye has a problem, what should it make us see when red and blue mix when one never actually transitions to the other in nature!?
We’ll come back to that. Let’s talk about your computer/phone screen for a second...
We’ll come back to that. Let’s talk about your computer/phone screen for a second...
Your screen is made up of tiny dots of color called pixels.
Under a microscope you’ll see they actually look more like traffic lights with the colors red, green, and blue
They can vary the amount of each to produce any color as our color wheel showed...
Under a microscope you’ll see they actually look more like traffic lights with the colors red, green, and blue
They can vary the amount of each to produce any color as our color wheel showed...
Well...not any color.
Violet is a color produced by blue transitioning to a color that *we cannot see* yet we can see violet itself.
This is why we call the invisible color “ultraviolet”
But for this reason, it is impossible for modern screens to even show it!
Violet is a color produced by blue transitioning to a color that *we cannot see* yet we can see violet itself.
This is why we call the invisible color “ultraviolet”
But for this reason, it is impossible for modern screens to even show it!
Try to take a photo of a rainbow, which will create true violet.
...it won’t work. You’ll have to view it on a screen and screens don’t have violet pixels.
If it shows that part at all, your phone will replace it with purple.
...it won’t work. You’ll have to view it on a screen and screens don’t have violet pixels.
If it shows that part at all, your phone will replace it with purple.
It makes you wonder when the last time was you even saw violet. Picture it now, are you sure you even remember?
Maybe you’ve seen it printed somewhere, no pixels no problem right?
Maybe you’ve seen it printed somewhere, no pixels no problem right?
Printed colors (bottom) use magenta, cyan, and yellow. When these colors are mixed, they produce...red, green, and blue!
From there, the vast array of colors on posters and billboards can be produced in the right combinations.
BUT NOT VIOLET.
From there, the vast array of colors on posters and billboards can be produced in the right combinations.
BUT NOT VIOLET.
The next time you see a rainbow in the sky or from a window in your home, take a look at true violet in all its glory.
Remember that problem the human eye had with perceiving a transition color from blue to red...something that cannot happen in nature?
Remember that problem the human eye had with perceiving a transition color from blue to red...something that cannot happen in nature?
It turns out, your eyes have receptors that are sensitive to three colors: red, green, and violet.
We were taught red, yellow, and blue are primary colors. In fact, only red is to our eyes.
Every other color is derived from mixing red, green, and...yep...violet!
We were taught red, yellow, and blue are primary colors. In fact, only red is to our eyes.
Every other color is derived from mixing red, green, and...yep...violet!
It makes you wonder why we don’t make screens and inks use violet instead.
We’ve all been walking around deprived of seeing a color we are perfectly built to see!
We’ve all been walking around deprived of seeing a color we are perfectly built to see!
It turns out the problem is alll in the slight spike in red. Do you see it under the hilltop of the violet curve?
It means we can’t use violet as a mixing color because it sensitizes our eyes slightly to red whenever used.
It means we can’t use violet as a mixing color because it sensitizes our eyes slightly to red whenever used.
We’d need to make pixels with a violet column (where the yellow column shows in this photo on the left)
But it would only get turned on when showing pure, true, violet.
But it would only get turned on when showing pure, true, violet.
But why do we see purple when we mix blue and red?
Buckle up, it gets complicated here.
This diagram shows the complete spectrum of colors we see when our three types of receptors are stimulated in different amounts...
Buckle up, it gets complicated here.
This diagram shows the complete spectrum of colors we see when our three types of receptors are stimulated in different amounts...
Draw a line between green and red in the diagram before. Now put a dot in the middle, and we get yellow, which we’d expect from how RGB screens work.
Now draw a line between blue and red and put a dot in between.
Notice we need a little more blue than red but we get there, the eyes come to a consensus that happens to be in violet (bottom left corner)‘s backyard.
But the only way to get true violet...is to get true violet.
Notice we need a little more blue than red but we get there, the eyes come to a consensus that happens to be in violet (bottom left corner)‘s backyard.
But the only way to get true violet...is to get true violet.
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