Recent progresses of electronics, essentially due to its miniaturization, are opening new fields that were just dreamed of, notably in astronomy. At start in paragraph 3, we introduce the time variation of images expressing the dual nature of the optical signal (ZO) and we expose several useful applications where the optical signal variations are not faster than CCD. However we prefered to initiate the article with a deeper question posed inadvertently in paragraph 2: what causes the rapid, w...