Yes and No!
LED's are normally one colour, but put three together of colours Red, Green and Blue and you can generate the different colours that you see by varying the mix of the intensity of each LED.
Same principle as in a CRT or LCD screen.
Your eye's in combination with your brains interpretation of the colours seen, produce the different colours we perceive.
Some of my solar garden lights have a single LED with red, green and blue chips inside and also inside is an IC that sequences the colours slowly.
I made "mood lights" that shine on the ceiling with millions of different colors. They use red, green and blue LEDs, each with its own fading oscillator.
A single LED junction produces only a single colour.
Multiple colours are produced by packaging different colour LED junctions very close together in a single package.
Ok here are my views I think you are interested to know about LED tv, now mostly in the market commercial television those are said by sales people "LED" tv are actually LED backlight LCD tv. So these work on principle of LCD. However there are LED tv's are even available which are mainly used in video wall application. These displays mostly uses a pixel as tri-color led's and the intensity of these all three color led's can be controllable simultaneously.......
as i given led diagram in #3 post use that one and if you want to glow to read then supply at only read pin if green then only supply green only and same for blue.
and combination of three using variable voltage you can get different color as you want.