ABSTRACT
In the physical world, light is not only part of the mainstream of energy that supports life; it also provides us with important sources of information. One can easily imagine that without light present civilization would never have emerged. Furthermore, humans are equipped with a pair of exceptionally good, although not perfect, eyes. With the combination of an intelligent brain and remarkable eyes, humans were able to advance themselves above the rest of the animals in the world. It is undoubtedly true that if humans had not been equipped with eyes, they would not have evolved into their present form. In the presence of light, humans are able to search for the food they need and the art they enjoy, and to explore the unknown. Thus light, or rather optics, has provided us with a very useful source of information whose application can range from very abstract artistic to very sophisticated scientific uses.
