A recent paper describes how laser pulses can be used in order to make us see novel colours. This post explains how that works, and asks if we could see similar colours through the use of optical illusions that induce negative afterimages (The answer is we’re not sure, but we do get some nice visulisations of different colour spaces on the way there). dynomight also created a generator for these kinds of illusions, which is very cool, and also linked out to this very early-noughties style website that I enjoyed.