I am a graphic designer and I really want to have knowledge about human colour perception but the longer I am looking for and the more I read the harder this topic seems to be. Physics is not my strong side so I need someone who check what I (think I) know so far and tell me if it's right or wrong, and answer my additional questions.
Below is what I think after reading many and many articles and seen some videos (sometimes with opposite answers or too far simplifies):
1. Nature of light
a) Ray of white light consists waves of different lengths.
b) Different wavelenghts give to the brain different impression of colour.
c) We can see it when a ray of light splits to the constituent waves in rain drops or when it go through material with higher density like glass prism. In those cases we can observe visible light spectrum which consists separate wavelenghts that give impressions of colours: violet, blue, cyan, green, yellow, orange, red.
2. Absorbtion and reflection
a) Surfaces of objects absorb and reflect some of lenghtwaves of white light ray.
b) Object that appears red absorb all the other wavelenghts and reflect only one wave from highlenghts range.
c) Object that appears green absorb all the other wavelenghts and reflect only one wave from medium range.
d) Object that appears blue absorb all the other wavelenghts and reflect only one wave from lowest range.
e) Object that appears yellow absorb all the other wavelenghts and reflect only one wave from range between medium and highest range.
f) Object that appears cyan absorb all the other wavelenghts and reflect only one wave from range between lowest and medium range.
g) Object that appears magenta absorb all medium wavelenghts and reflect simultaneously two waves from the lowest and the highest ranges. (← correct?)
h) Object that appears black absorb all wavelenghts and reflect no light.
i) Object that appears white absorb none of the wavelenghts and reflects all together (reflects whole white light ray).
a) In eye on the retina there are receptors called cones and rodes. Cones are responsible for colour interpretation.
b) There are three types of cones – receptors of small wavelengths [S] (mostly sensitive for ranges giving blue hues impressions), receptors of medium wavelenghts [M] (mostly sensitive for ranges giving green hues impressions), receptors of large wavelengths [L] (mostly sensitive for ranges giving red hues impressions but having small range giving violet hues impressions.)
c) Ranges of cones partially overlap.
d) Lightray, depending of it's composition after reflect from object, can stimulate one, two or all three cones.
e) Pure red/green/blue object reflect pure L/M/S wave and stimulate only one of cones at the time: red/green/blue.
f) Wavelenghts that lies between overlaping ranges of the cones stimulates them both eg. wavelenght responsible for yellow colour impression activate M ("green") and L ("red") cones, and wavelenght responsible for cyan colour impression activate S ("blue") and M ("green") cones.
g) Somehow magenta colour impression ("bright pink" or "intensive purple" as you can say, different from violet) appear when both S and L cones are activate by the one lenghtave from the lowest range and one wavelenght from the highest range. Magenta impression is not cause by one particular wavelenght that's why it's not appear in visible spectrum and rainbow. (← right?)
h) White impression appear when all three cones are stimulated with the same, high intensity.
i) Grey impression appear when all three cones are stimulated with the same, medium intensity.
j) Black impression appear when all three cones aren't stimulated (object absorb all the wavelenghts and doesn't reflect any of them to the eye).
k) Other colours that we can name such as brown, light pink etc. that we can't find in visible spectrum are actually variations of the colours include in spectrum but with different saturation and lightness. (← true?)
Please, If someone of you studied physics, optics, biology, knows the subject can help me to understand this I will be very gratefull. I am looking for these answers for a long time.
Let me know if this above is correct. Feel free to use simply examples and comparsions like you were explaining it to the child.