Multi-Primary Color Display Emerges as Next-Gen Color Reproduction Technology

Can anyone explain how this works? Humans have 3 (sometimes 4) cones, so I thought that going beyond 3 primaries wouldn't increase the perceivable gamut.

Update: thanks for all the great explanations!

I don't know either, but if we visualize the RGB color space as a triangle that is entirely contained within the weird shape that represents the set of all colors the human eye can perceive ( https://en.wikipedia.org/wiki/RGB_color_model#/media/File:CI... ), presumably the idea is to cover more of that human-perceived space via a quadrilateral with four anchor points rather than a triangle with three. Presumably the "C" in "RGBC" stands for cyan, and in the linked image the cyan portion of the color space is particularly poorly represented.

We have a very "fuzzy" visual perception. I remember seeing an RGB response curve of the human vision mechanism once. I doubt it was measured. Maybe they extracted it from the CIELab stuff.

Anyway, things like the green (or blue -can't remember) receptor have a strong curve in the green spectrum, but also a "bump," over in red (I think).

We're an organic mess.

Looking at RGB curves for LEDs, they are three perfect little mountains. No "bumps," anywhere.

I guess that the goal is to try to mimic the "messy" human visual perception.

Also, expect these monitors to be non-cheap. Companies like Eizo are having a difficult time, justifying their prices, these days.

I don't have an answer, I'm just wondering out loud.

Cone cell activation is complicated. Displays with three well chosen primaries are economical and effective, but they aren't intended to produce every perceivable color. And our chromaticity diagrams, that pointy splotch that's often used to compare display gamuts, is based on a "standard observer" that is a simplified model for human perception.

An ideal pixel would be able to emit any kind of electromagnetic radiation of any intensity, kind of fun to think about but unrealistic and impractical.

What additional primaries mathematically do is expand a gamut from a triangle to a convex polygon. While ten or a hundred primaries would be bonkers, I bet we could fit a quadrilateral or a pentagon to the perceivable gamut in ways that'd see some gains.