After Violet

One thing I often wonder is what ultra violet light actually looks like. We can't see ultra violet light because it won't go through the lenses on our Eyes and we don't have cells that will detect that light directly. I was thinking that if ultra violet light was visible then it wouldn't be violet, it would be a completely different colour that we can't imagine. Ultra violet light is very thin, much thinner than the cells in your retina and Infra red light is thicker than the cells in the retina. 

Not only would we see an extra colour. We would see several because there would be different mixtures with ultra violet light present. Ultra violet and yellow mixed together would make yet another colour.