Ibn Al Haytham discovered in this tribulation the properties of light and wrote his well-known book (Optics) during the period that he spent in prison. He says that light contains straight lines falling from self-illuminating figures, like the sun, lit wide like a candle, or reflected like moonlight carrying images. This expression is crucial because it is the same expression that Newton uttered centuries later about the nature of light (lazemtefham.com). Ibn Al Haytham also proved the fact that light comes from objects to the eye and not the other way around as was believed at the time, and he attributed the principles of the invention of the eye to