2015 is the International Year of light according to the organization of the United Nations (UN).
At a time when most industrialized countries are making efforts to create alternative energy sources more environmentally friendly, the UN decided to dedicate this year to the light. It is a global initiative that aims to raise awareness among citizens around the globe to its importance and optical technologies in society. To celebrate the light in its various forms, are already being prepared various activities aimed at audiences of all ages and different cultural levels.
With the advent of electricity in the twentieth century, many people have forgotten the luxury that means you can access daily to this energy form. At the same time, in developing countries, there are millions of people who have no access to electricity and is also the problem that the UN wants to emphasize with the anniversary.
The International Year of Light still coincides with several important milestones in the physical study of light's field, as the work on optical Ibn Al-Haytham in 1015; the wave behavior of light, proposed by Fresnel in 1815; the electromagnetic theory of light, proposed by Maxwell in 1865; Einstein's work on a photoelectric effect (1905) and on the link between light and cosmology in the context of general relativity (1915); the discovery of the cosmic microwave background in microwave by Penzias and Wilson in 1965, and the works of Charles Kao (1965) on the use of fiber optics in telecommunications.