Hypnotic reflections
On Saturday I was at an end of term party at our principals house and noticed this interesting mobile so filmed it with my phone. At first sight it looks like some sort of Moire fringe interference effect but on second thoughts I don't think it is. Its made out of a series of reflective squares arranges at different angles. The intriguing aspect is the way that the whole of a square reflects the same colour. What I think is happening is that each square is acting like a lens reflecting light from its focal point. By the time I noticed this it was late and I was on my way out of the house so didn't have time to perform any experiments but I'm going back at the end of the week so can test my hypothesis. It's OK, he is a physics teacher too.