2015 as the International Year of Light and Light-based Technologies

The year 2015 represents over ten centuries, since the publication of the great works on optics by the medieval Arab scholars, during the Islamic Golden Age.  It is significant therefore that the UN General Asembly recently declared 2015 as the International Year of Light and Light-based Technologies.


015 has been at last proclaimed as the International Year of Light and Light-based Technologies (IYL 2015).  This was done on Friday the 20 December, during the 71st Plenary Meeting of the UN General Assembly 68th Session.  The move has been lauded by a number of scientific societies and institutes.  The IYL-2015 partnership, formed in 2010, is a cross-disciplinary educational and outreach project with more than 100 partners from more than 85 countries, accompanied by the UNESCO International Basic Sciences Program.  A resolution welcoming and endorsing an International Year of Light in 2015 was adopted by the UNESCO Executive Board at its 190th session which took place at the UNESCO Headquarters in Paris from the 3rd – 18th October, 2012.  UNESCO formally submitted to the UN on 6 November 2013.  It is an effort of several years and the persuasion of the numerous optics-related organizations, which eventually lead to the proclamation.  The text of the resolution, which was adopted as part of a more general agenda item on science and technology for development, stated: “Applications of light science and technology are vital for existing and future advances in medicine, energy, information and communications, fiber-optics, astronomy, architecture, archaeology, entertainment and culture.”


year of light 2015

The central role of light needs no elaboration.  On the very basic level it provides us vision.  On the most fundamental level through photosynthesis (mostly in the green leaves of the plants), light is necessary to the existence of life itself.  In humans skins, the sunlight induces the synthesis of the essential vitamin-D.  The science of light is applied in the technological field known as photonics, and this theme addresses the important ways that photonic devices impact on areas such as medicine, communications and energy.  When harnessed, the light-based technologies can promote sustainable development and provide solutions to global challenges in energy, education, agriculture, health and well-being.

Light is more than just science and technology.  Light matters to all of us.  The IYL-2015 will create a forum for scientists and engineers and all others inspired by light to interact both with each other and with the public so as to learn more about the nature of light and its many applications.  IYL-2015 is a tremendous opportunity to ensure that policymakers are made aware of the problem-solving potential of light technology.  As light becomes the key cross-cutting discipline of science and engineering in the 21st century, it is essential that the brightest young minds continue to be attracted into careers in this field.

The year 2015 commemorates a remarkable series of important milestones in the history of the physics of light.  A number of major scientific anniversaries will be celebrated in 2015, starting with the early work on optics by the Islamic scholar Ibn Al-Haytham in 1015.  The notion of light as a wave proposed by Fresnel in 1815; the electromagnetic theory of light propagation proposed by Maxwell in 1865; Einstein’s theory of the photoelectric effect in 1905; Einstein’s embedding of light in cosmology through general relativity in 1915; the discovery of the cosmic microwave background by Penzias and Wilson in 1965; and Charles Kao’s achievements in 1965 concerning the transmission of light in fibers for optical communication.

The year 2015 represents over ten centuries, since the publication of the great works on optics by the medieval Arab scholars, during the Islamic Golden Age.  Abu Saad Alaa Ibn Sahl had translated Greek books on optics including Ptolemy’s Optics.  Ibn Sahl in 984 wrote his book, On The Burning Instruments.  Ibn Sahl’s book is both experimental (he provides the mechanical means to draw the conic sections) and theoretical.

In his book published in 984, Ibn Sahl, stated the law of refraction of light (commonly and erroneously known as the Snell’s law after Dutch scientist, Willebrord Snellius, 1580-1626) long before Snellius himself.  Ibn Sahl was well known among his colleagues and students.  Abu Ali al-Hasan ibn al-Haytham (965-1039, known as Alhacen/Alhazen, the Latin transliteration of his first name al-Hasan) wrote several books on optics acknowledging his mentor Ibn Sahl.  Ibn al-Haytham authored fourteen books on optics alone.  His magnum opus Kitabl al-Manazir (Book of Optics) earned him the title of father of optics.  This book was translated into Latin in 1270 as Opticae Thesaurus Alhazen, and many prominent European scientists including Leonardo da Vinci (1452-1519), Johannes Kepler (1571-1630), Roger Bacon (1214-1292), Isaac Newton (1643-1727), and many others benefited from his theories in this field.

The IYL-2015 is a time to recognize the Greek and the Arab pioneers of optics.  Importantly it is a time to reflect on the decline of science in the Arab and Muslim world.  It is an excellent opportunity to address the theme of the renaissance of science in the Muslim countries.

refraction of light


Above: The diagram on refraction of light from the book by Ibn Sahl (published in 984)


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  2. David C Lindleberg, Medieval Islamic Achievement in Optics, Optics & Photonics News, 14(7) 30-35 (July 2003); Akhlesh Lakhtakia, Optics in Medieval Islam, Letter in Optics & Photonics News, 14(9) 6 (September 2003). 
  3. Zakaria Virk, Europe’s Debt to the Islamic World, Review of Religions, 98(07) 36-52 (July 2003). 
  4. Sameen Ahmed Khan, Medieval Arab Understanding of the Rainbow Formation, Letter in Europhysics News, 37 (3), pp. 10 (May/June 2006).  (Publication of the European Physical Society). 
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  6. Sameen Ahmed Khan, Report of the First International Conference on Arabs’ and Muslims’ History of Sciences, (24-27 March 2008, University of Sharjah, Sharjah, United Arab Emirates), Islamic Voice, Vol. 21-05, No. 257, pp. ?? (May 2008); American Journal of Islamic Social Sciences (AJISS), Vol. 25, No. 3, pp. 158-160 (Summer 2008). 
  7. M. Salih, M. Al-Amri and M. El-Gomati, The Miracle of Light, A World of Science, 3 (4) 2-7 (October-December 2005). http://www.unesco.org/science/infocus_full_oct_05.shtml;  Natural Science Quarterly Newsletter, UNESCO Publication No. 385 (February 2006), (Foundation for Science Technology and Civilization, UK, http://www.fstc.org.uk/).


(Dr Sameen Ahmed Khan is a Professor at the Engineering Department, Salalah College of Technology (SCOT), Salalah, Sultanate of Oman.He can be reached at rohelakhan@yahoo.com or at http://SameenAhmedKhan.webs.com/)