Olo is a good example. It’s due to a quirk of human perception and the structure of our eyes. They basically designed a machine to try and stimulate the green detecting cones without stimulating the red detecting cones. Normally if something pure green hits your eyes, it stimulates those red cones too. So this is something our bodies are capable of perceiving but not something that we can ever perceive under normal circumstances.

Is it a “new color”? Not exactly. Did it take a good bit of imagination to conceive trying to get our brains to see it? Yes.