International Day of Light – 16 May

International Day of Light – 16 May

International Day of Light (IDL) is observed on the 16th of May to recognize the importance of light and optics in society, science, and culture, and the continued importance of the study of light. It is a global initiative that provides an annual focal point for the continued appreciation of light and the role it plays in science, culture and art, education, and sustainable development, and in fields as diverse as medicine, communications, and energy.

The broad theme of light will allow many different sectors of society worldwide to participate in activities that demonstrate how science, technology, art, and culture can help achieve the goals of UNESCO – education, equality, and peace. This day is a call to strengthen scientific cooperation and harness its potential to foster peace and sustainable development.


The International Day of Light officially declared by UNESCO has been celebrated since 2018. May 16 was selected as the IDL to commemorate the anniversary of the first successful operation of a laser, in 1960 by physicist and engineer, Theodore Maiman. The laser is a perfect example of how a scientific discovery can yield revolutionary benefits to society in communications, healthcare, and many other fields. However, the International Day of Light is not just about lasers and science. It also includes aspects of art, culture, entertainment – everywhere light is present in fact! This day is a call to strengthen scientific cooperation and harness its potential to foster peace and sustainable development.

In 2015, to raise global awareness of the achievements of light science and its applications, the UN observed the International Year of Light and Light-based Technologies 2015 (IYL 2015). The event helped establish links and collaborations between decision-makers, industry leaders, scientists, artists, social businesses, NGOs, and the public at large. Following the success of IYL 2015, Ghana, Mexico, New Zealand, and Russia placed a resolution before the UNESCO Executive Board supporting the idea of an International Day of Light. It was adopted on September 19, 2016, at the Board’s 200th session at the UNESCO HQ in Paris, France. The Board decision was endorsed by the UNESCO General Conference at its 39th session on November 7, 2017, and the first IDL was held on May 16, 2018.

According to the International coordinators of the International Day of Light, the events have reached an audience of more than 2 million with face-to-face activities, social media posts, video messages, and other campaigns carried out nationally and worldwide.

Humans have always felt –and still feel– a fascination for light, mainly thanks to those magnificent organs of the human body which are the eyes. Luminous phenomena such as rainbows, aurora borealis, sundogs, Fata Morgana, or just the rising and the setting of the Sun still amaze us as they did our ancestors before us. The truth is that light affects every day of our lives. The light emitted by the Sun plays a fundamental role in the development of life on Earth and it is the main source of energy for our planet.

Light is everywhere in our lives, but despite its ubiquitous nature, we are often unaware of the crucial role it plays in our daily lives. From well-established optical communication systems, photographic and video sensors, to the latest developments in the very extensive fields of optical sensing, light is a fundamental transversal component.

Light is at the origin of life, it has inspired beauty, painters, poets, and architects… and is essential to photography, cinema, theatre, or television because there is no doubt that light affects the emotional response of the audience. We just need to look around us to verify that the numerous applications of light in science, engineering, architecture, medicine, communications, culture, art, and leisure have revolutionized society.

How it is observed

IDL is celebrated around the world with a variety of different light-focused events, including UNESCO’s Illuminating Education conference, promoting careers in the physics of light, and the use of light to promote science to the general public. Every May 16th of each year, millions of people around the world will reflect on how wonderful light is and the many ways in which light and light-based technologies can improve our lives. Learn more about the international event at

Suggested Read: Important Days In May

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Simmi Kamboj

Simmi Kamboj is the Founder and Administrator of Ritiriwaz, your one-stop guide to Indian Culture and Tradition. She had a passion for writing about India's lifestyle, culture, tradition, travel, and is trying to cover all Indian Cultural aspects of Daily Life.