Tonight, I will talk about "Color Vision and Human Diversity".

There are many colors in our surroundings.

When we walk around the town, the various colors of signboards and show windows go into our eyes.

However, not all people see the same color as you.

They are Salvia flowers! Flowers of sage.

On the left is the original picture, and on the right is a simulation of one type of color vision.

That I made.

This type of color vision is called protanopia, a kind of red-green color-blindness.

The flower petals of Salvia look similar to its leaves.

Therefore, this flower is hard to see for people with this condition.

People who have the inability to distinguish the differences between colors, have the condition

called " Color Vision Deficiency" (CVD), AKA daltonism or color-blindness.

I will show you some other examples.

These are cherry tomatoes. I picked them on my uncle's farm.

He is a tax accountant but also a good farmer.

On the right is a simulation picture of another kind of "Color Vision Deficiency" called Deuteranopia.

It is difficult to find ripe tomatoes for Deuteranopes.

Red and green are not the only colors that can cause confusion for "Color Deficient People",

but also "pink and cyan", "brown and purple", "orange and ochre" and others.

These are artificial flowers of pink and cyan.

I got them from a hundred-yen store near my house.

Totally, only two handred Yen.

Both flowers look completely the same color for Protanopia.

Color Deficient People h can sometimes feel inconvenience in their daily life.

This is Hida beef. Do you know Hida beef?

Hida beef is a famous brand of beef in Japan, like Matsuzaka beef or Kobe beef.

This beef is very tender and tasty--really delicious!

I like it very much.

I got it in Gifu when an academic meeting of color science was held in Gifu city.

The best way to eat Hida beef is Sukiyaki!

When we cook Sukiyaki, 4 or 5 people eat together.

We put a gas stove and pot in the center of the table and cook the Sukiyaki at the table.

Once the cooking is started, you should watch the pot carefully, and take the beef as soon as it is cooked.

Otherwise, someone else will take it.

But it is difficult to find the cooked beef for "Color Deficient People",

because raw beef and cooked beef are the same color for them.

So, they always lose the Sukiyaki battle.

How common is it?

Well, about 5-8% of men and 0.2% of women are "Color Vision Deficient ".

This number includes various degrees of deficiency.

This slide shows the distribution of "Color Vision Deficiency " in males around the world.

As you can see, "Color Vision Deficiency " is found all over the world.

In the USA and Europe about 8% of men, or one in twelve,

and in Japan and most of Asia about 5% of men, or one in twenty, are color vision deficient.

How do we see color?

We have a retina at the back of the eyeball.

There are 3 kinds of cone cells in the retina.

Each cone has its own spectral sensitivity.

It means we have 3 kinds of light sensor (color sensor) to see color.

The output of the cones is finally sent to the brain. Then, the brain interprets the color.

If one of the 3 kinds of cones is absent,

or if the peak spectral sensitivity is shifted in one cone, "Color Vision Deficiency " will occur.

These deficiencies are genetic, inherited from the parents and is congenital.

There are 3 kinds of common color vision deficient types

depending on which cone is abnormal.

They are Protan, Deutan and Tritan.

Isaac Newton said, "The Rays are not coloured".

The visible color for every person may be different.

Even if we see the same spectral light, it may be perceived differently by each person.

It is because we "see " the color in the brain.

These are some examples of confusion color pairs for "Color Deficient People".

Shown on the left side are confusion colors for Protans. And on the right side are for Deutans.

These examples are by no means complete. There are many other confusion color pairs.

This confusion has led to the concept of "Color Universal Design",

using perceptible colors for both "Color Normal People" and "Color Deficient People".

I will show you a good example of "Color Universal Design".

This slide shows a previous version of an information board from Asahiyama Zoo,

a very popular zoo in Hokkaido, Asahikawa.

On the right is a picture of what Deuteranopes see.

Dark brown areas are hard to distinguish from the dark green areas.

This slide shows a revised version of the information board.

The dark green has become lighter.

Now we can see that it is much easier to distinguish the different areas of zoo for Deuteranopes.

So how to increase awareness?

This is an application software I have developed called the "Chromatic Vision Simulator".

This is for "Color Normal People"

and it can show how the 3 most common types of gColor Deficient People h perceive color in real-time.

It works on smartphones.

This application is very useful for raising awareness and applying "Color Universal Design" principles.

The "Color Universal Design" is a great idea.

But it is only effective for artificial things.

Things in nature such as flowers, vegetables, Sukiyaki beef cannot be redesigned.

For this problem, I have developed a portable color assistance tool, called the "Chromatic Glass ".

It also works on smartphones

and It increases color visibility and enhances the ability to distinguish color for "Color Deficient People".

Allow me to demonstrate.

This is the screen of my iPhone.

I am launching Chromatic Glass.

There are Salvia flower again.

This application also has a simulation mode. Turn it on.

This screen is what Protanopes see.

You can hardly distinguish the flowers. But, it becomes visible with this software.

Thank you.

These are cherry tomatoes.

It is a Deuteranopes simulation.

But they can find ripe tomatoes with this software.

OK?

These are released for free.

At the moment, there are about 47,000 users throughout the world.

Now you may be thinking that

life for "Color Deficient People" must be very difficult because they can only see limited colors.

However, nature is a great compensator.

"Color Deficient People" can actually have superior vision to "Color Normal People" in certain conditions.

For example, at night, under the sea, in fog...

According to a report from the second world war,

"Color Deficient People" can find soldiers who wear camouflage suits in the jungle.

And my friend, who is color deficient, said, he can see the landscape even in heavy snowstorms when driving.

Since you may still be skeptical, I will show you an example.

Can you read it?

I think most people can not read it.

Please look at this through the "Chromatic Vision Simulator".

This is a screen of my iPhone again. The "Chromatic Vision Simulator" is running now.

OK?

In the simulation picture, you may be able to read it.

Can someone read it?

Yes. This is 46.

Sometimes "Color Normal People" are superior to "Color Deficient People ",

and sometimes "Color Deficient People " are superior to "Color Normal People".

It can be said that "Color Vision" is personality, "Color Vision" is individuality.

Each person is different. We all have our own strong points and weak points.

If I go camping with my color deficient friend,

I can help him to find ripe, wild-strawberries in the fields,

and he can help me to find insects in the forest.

So, we have to help each other mutually.

Thank you.