Right now, all current monitors use three (or four) primary colors to create their color, which could never allow them to produce all colors that can be seen by the human eye; in fact, their colors will always be inside a triangle on the xyY diagram of all possible colors.But we could decide to replace these color filters with something such as Lyot filters, which can be tuned, similarly to LCDs, to allow only light whose wavelength is higher/lower than a certain value to pass through. This would mean that we could basically create color filters that can be adjusted to produce any color, by replacing each pixel with two stacked filters, which allow a range $[a, b]$ to pass, and a third filter next to it which allows the range $[c,\infty)$ to pass through.Using Mathematica, I have tested that a mapping between these three values is enough to create any possible $x$, $y$ and $Y$ in the CIE xyY color space:So, in other words, the range of $$\text{XYZ}(a,b,c)=\int_{[a,b]\cup[c,\infty)}\text{I}(\lambda)\cdot(\overline{x}(\lambda),\overline{y}(\lambda),\overline{z}(\lambda))$$, where $\text{I}$ is the illuminant, is enough to produce the color of any object that can be illuminated by that illuminant.So, my questions are: Are there already any such displays that can produce any visible color, and if not, then why not?Could this actually be done in practice?
Display that supports full CIE xyY color space
color science