Light and Light—based Technologies Advancing Human Civilization and Progress

2015 is the international year for light and light-based technologies， and its short form is 2015 international light Year. Based on the importance of light and light-based technologies to the life of people of the world and the future development of multiple levels of the global community， UN made the resolution with the hope to raise people's awareness of and strengthen the education on optical science & technology through much publicity， which is very important for various countries to deal with the challenges of sustainable development， energy and community health and enhance the quality of life.

In nature， light exists everywhere， and plays a crucial role in human life. Viewing from the most basic level， light is the origin and basis of life， and plants stores energy which can enter lifecycle through photosynthesis. Since the birth， human's awareness and use of light has constantly deepened. Hundreds of thousands of years ago， primitive men got artificial light source， a unique tool for human's progress and development， which can be used to illuminate in the dark. Wonderful optical phenomena in nature are closely related to human life， rainbow， secondary rainbow， lunar halo， aurora and other natural phenomena attract people to explore the secrets behind them. In the continuous exploration， optical science gradually develops.

2015 happens to be an anniversary of a series of important milestones in the history of optical science. In 1015， Ibn al—Haytham published the earliest optical works； in 1815， Fresnel proposed the concept of light waves； in 1865， Maxwell put forward the theory of photo electromagnetic propagation； in 1905， Einstein proposed photoelectric effect； in 1915， Einstein included light as an intrinsic element of cosmology through the general theory of relativity； in 1965， Penzias and Wilson discovered cosmic microwave background， and Charles Kuen Kao proposed fiber optic communication... These splendid names in the history of optical science represent human's constant exploration of the world. Light industry has become a major driving force to the economy. And the application of various light-based technologies are very important to the progress of pharmaceuticals， information and communication， material， astronomy， architecture， archaeology， national security， entertainment and culture. Extensive use of laser technology in medical field has made tremendous contributions to human health. Solar energy is a clean and environmentally friendly energy source， and has great significance for the sustainable development of human society.

Advances in fiber optic technology directly contribute to the unceasing progress of technologies in the field of information and communication， which accelerates the globalization. The development of optical telescope has promoted the process of human exploration of the universe. In the future， light-based technologies will provide more and more solutions for the problems the world faces， especially challenges in energy， education， agriculture， life and community health care， etc.， and become an important driving force for many countries to achieve and exceed UN Millennium Development Goals.

There is still much room for light-based technologies to develop in the future. Many appearing in science fictions can be realized as technology advances. Human exploration of the world is endless， therefore， light-based technologies will certainly continue to develop， promote social progress， and illuminate people's lives.