International Day of Light

INTERNATIONAL DAY OF LIGHT 2025 AT SECHENOV UNIVERSITY (PAST EVENT) Join the Light Science and Art Festival during the open doors International Day of Light 2025 event at Sechenov University!   Lectures and masterclasses from Biomedical Optics and Photonics scientists, magic Tesla coils, VR games, quests and more are waiting for you!  Meets with us at Mokhovaya str., 11/10 on May 16 (14.00 local time). Full details here Contact: Dr. Gennadii Piavchenko (Sechenov University) Date:16/05/2025 - 16/05/2025 Location:Moscow, Russia

VI-th ONLINE-QUIZ FOR YOUNG PHYSICISTS FROM THE PHYSICAL BRANCH OF THE RUSSIAN ACADEMY OF SCIENCES (PAST EVENT) RAS with contribution of Moscow State Pedagogical University perform VIth Online-quiz on Physics, Astronomy and related fields for Scholars. It has been launched in 2020 and join together >1000 participants annually (in 2024 from Russia, China, Kazakhstan, Belarus, Tajikistan). Young physicists obtain the possibility to communicate with leading world-wide recognized scientists. The tasks of this quiz are non-standard, requires physical savvy, prudence and horizons. The winners will be awarded by special honor diploma and prizes at the special meeting with the President of RAS G.Ya. Krasnikov. While photonics is very important for modern science and technology a lot of questions have direct relations to this field. The final round of the Quiz on May 16, 2024 has a special relation to the International Day of Light. Full details here Contact: Corr. memb. RAS Andrei Naumov...

University of Tasmania International Day of Light. Join us on May 16th to honor the incredible impact of light in science, culture, art, education, and sustainable development. This special day marks the anniversary of the first successful laser operation by physicist Theodore Maiman in 1960.  Event Highlight: IDL2025 at University of Tasmania Create your very own suncatcher!  Full details here Contact: Vanessa Henry (University of Tasmania ) Date:21/05/2025 - 21/05/2025 Location: Launceston , Australia Register to participate!

Celebrate IDL with a public lecture “From laser to teleporter - will dreams become reality?”  The lecture will discuss the quantum properties of light, which are the basics of much Quantum Tech being developed today. There will be some exciting demos with lasers and the photon clicker. The event is organised by the ANU Optica and SPIE Student Chapter and TMOS, with help from the ANU Research School of Physics, Questacon, and the IEEE Photonics Society. When: 20 May 2025, 5.30 pm for 6.00. Where: Physics Auditorium, Research School of Physics, Building 160, The Australian National University . From laser to teleporter – will dreams become reality?  |Prof. Hans Bachor | Public Lecture Full details here Contact: Sarah Dean (ANU Optica and SPIE Student Chapter and TMOS) Date: 20/05/2025 - 20/05/2025 Location:Canberra, Australia

AstroKids! Light Benders Celebrating International Day of Light. With your kids, learn how telescopes harness light to enable us to see the universe! Participants will: Go on a kid-oriented tour of 100+ year old telescopes and buildings . Watch “Telescope” – an AstroTour Production Hands on activities about light and space. View the Sun using Solar projection (weather permitting) Full details here Contact: Kirralee McLoughlin (Ballaarat Astronomical Society) Date: 16/05/2025 - 17/05/2025 Location: Ballarat, Australia

The kit Chemistry and Light is designed for teachers who want to fascinate their students with attractive luminescence and photochemistry experiments. The quick and easy to perform experiments help to illustrate in a fresh and modern way a whole range of elementary and middle school topics, enabling the students to get a wonderful hands-on chemistry experience. Test kit. Kit Student. Kit Standard. Kit Professional.

Chemiluminescence is the emission of cold light as a result of a chemical reaction. In a chemiluminescent reaction, reactive intermediates are formed which enter electronically excited states. Subsequent transition back to ground state is accompanied by a release of energy in form of light. The mechanism is depicted in Fig. 5. Fig. 5: Scenarios of a chemiluminescent reaction Compounds A and B react together forming C* and D while C* is in electronically excited or energetically rich state. C* can get rid of its extra energy by several pathways:Non-productive non-radiative transitions producing heat (undesirable process) Direct deexcitation of C* by a radiative transition with concomitant emission of light characteristic for C* Indirect deexcitation – C* transfers its extra energy to a a suitable fluorescer that can act as a temporary energy acceptor and then emit the energy in form of light. The emission spectrum is then dependent on the structure of fluorescer. This can be used with a...

The last luminescent phenomenon is pyroluminescence . It is the emission of light from molecules or atoms that were previously excited by heating to high temperatures, for example by a flame. The classical examples include salts of alkali metals and alkali earth metals in the flame of Bunsen burner. The temperature of Bunsen burner is sufficient for thermal excitation of sodium, potassium, lithium or calcium atoms. Another very attractive experiment is burning of trimethyl borate. During this process, an excited intermediate is produced (BO*) which emits a characteristic green light. Fig. 8: Trimethyl borate flame with a characteristic colour

Fluorescence is a physical phenomenon during which a material is electronically excited by absorption of a quantum of electromagnetic radiation and subsequently emits light. Fluorescence represents a subcategory of cold-light emission – luminescence. The origin of fluorescence is related to the material´s ability to absorb electromagnetic radiation and subsequently release the extra energy in form of a characteristic emission radiation. The irradiated material enters a so called high energy “excited state”. The return from the excited state to the ground state is linked to the emission of a photon. When this happens instantly (<10-8 s), we speak about fluorescence. The wavelength of the excitation radiation is almost always shorter (and therefore higher in energy) than the emission radiation. (There are only very few exceptions to this rule).The typical examples of the excitation radiation are light in UV region, visible light, X-Rays and radioactivity. In the latter case we speak ...

Experiments with hydrogels In the Chemistry and Light kit, you have the opportunity to combine the fluorescence module with the hydrogel module in an attractive way to prepare fluorescent hydrogels (often described as "artificial slimes", which have an impressive appearance and interesting mechanical properties.) These hydrogels are marked by their unusual behavior as non-Newtonian liquids. During the preparation of hydrogels , the low molecular weight water-soluble polymer of polyvinyl alcohol is coordinated with the molecules of the crosslinking reagent. The result of this crosslinking is an abrupt increase in the molecular weight of the formed polymer and the formation of the semisolid hydrogel. In the experiment, you can dramatically demonstrate the effect of molecular weight on the properties of a polymer. Formation of a polyvinyl alcohol-based hydrogel is one of the most popular experiments and it also demonstrates the effect of pH on the shift of the reaction equilib...

Phosphorescence is a physical phenomenon closely related to fluorescence. The main criterion that is used to distinguish between them is the length of emission radiation. While during fluorescence excited molecules emit light instantly (<=10-8 s), during phosphorescence, excited molecules undergo a transition to a lower lying metastable state that can last for longer time (usually seconds to hours). The remaining transition from the metastable state to the ground state releases energy in form of light. Fig. 4: Schematical comparison of fluorescence and phosphorescence The difference between fluorescence and phosphorescence can be easily compared with kicking a ball from a valley to a nearby hill (Fig. 4) In case of fluorescence, the ball reaches an unstable position (excited state) and immediately falls back into the valley (ground state). In case of phosphorescence, the ball rolls down from the peak to a plateau (metastable state) where it can reside for a while and continue falli...

Cyanotypes. Photochemical blueprinting (also known as cyanotype process , from the Greek kyanos-blue) is one of the historically oldest photographic techniques that produce intensively blue pictures. Today it is classified as the member of a family of alternative photographic processes. This process was developed in 1842 by the English natural scientist and astronomer Sir John Frederick Herschel (1792-1871). Cyanotype was thus the third photographic technique after daguerrotype and talbotype (calotype), with which stable photographic pictures could be obtained. Unlike previous silver-based techniques, cyanotype is based on the light sensitivity of iron(III) complexes, which makes it comparatively inexpensive. Herschel himself is the author of today’s common expressions such as negative, positive, photograph and snapshot. Figure 1: Sir John Frederick Herschel, English astronomer, mathematician, chemist and pioneer of photography, especially the cyanotype The intensive blue color of cy...

Mechanoluminescence Mechanoluminescence (ML) represents one of the most interesting and least understood luminescence phenomena. ML means that light is emitted during mechanical stress of solids. Mechanoluminescence is divided into several categories depending on the nature of the mechanical stimulus. The most common form is triboluminescence, also called fractoluminescence which takes place when crystals are mechanically stressed (crushing, milling, rubbing) leading to separation of crystal surfaces. The historically first written example of triboluminescence comes from the English philosopher Francis Bacon from his 1605 book „Of The Advancement of Learning“ and later in „Novum Organum“ from 1620. In these books, Bacon describes appearance of light during crushing of cane sugar. It is known that some Native American tribes used triboluminescence of certain minerals, like quartz, for ceremonial purposes. Piezoluminescence is another subcategory of mechanoluminescence. It differs from ...

We are counting down the days to May 16, 2025, which will see the eighth celebration of the UNESCO International Day of Light, one of the most anticipated science events on the global calendar of United Nations observances. Since its inception in 2018, over 2800 activities and events have taken place in more than 100 countries, reaching and inspiring millions worldwide. We would like to thank you all for the hard work that has made the International Day of Light such a success. As you will see from our global calendar , activities are being organised worldwide for 2025, and we look forward to some fantastic celebrations. Indeed, some have already taken place; One of the unique features of the International Day of Light is the way it brings together so many diverse communities, and this is reflected in the tremendous range of topics that will be celebrated - science and technology, lighting and lighting quality, astronomy, education and more. In addition, 16 May is also the United Nati...

Celebrate the International Day of Light with us! Date: May 14 Time: 5:00–7:00 PM Location: USYD Nanoscience Hub  Join us for a unique science and art poster exhibition, featuring images submitted by students and researchers that highlight their work in optics and photonics. Enjoy guided lab tours and discover some of the exciting research happening behind the scenes. Network with fellow students, researchers, and professionals. Explore optics demonstrations. Whether you're passionate about science or simply curious, everyone is welcome. Registration is required — sign up here Full details here Contact: Leila Vatandoust (The University of Sydney, SPIE and Optica Student Chapter) Date 14/05/2025 - 14/05/2025 Location: Sydney, Australia

PHOTONICS: WORLD OF LASERS AND OPTICS (19TH INTERNATIONAL EXHIBITION) The exhibition was attended by representatives from Russia, China and Belarus etc, including companies, scientific institutions, universities, societies, in particular the Russian Academy of Sciences, Rosatom, Shvabe, VPg Laseruan. The event featured 236 companies, showcasing photonics innovations across 4,400 sq. m. Over 11,000 visitors attended, including students and industry experts. The program included 20+ events, such as the Photonics Congress, the Russia-China roundtable, scientific meetings and panel discussions, highlighting quantum tech and optical sensors. Full details here Contact: Corr. memb. RAS Andrei Naumov (Laser Association; Expocenter) Date: 01/04/2025 - 04/05/2025 Location: Moscow, Russia

Extended meeting of the Scientific Council on Optics and Photonics of the Physical Branch of the Russian Academy of Sciences. The council discussed key 2024 results and trends in optics and photonics. The priority research directions have been discussed: Bio-photonics (medical imaging, diagnostic systems), Quantum technologies (optical clocks, computing), Nano-optics (femtosecond lasers, THz systems), Photonic instrumentation (optical sensors, fiber technologies). Full details here Contact: Corr. memb. RAS Andrei Naumov ( Russian Academy of Sciences , Branch of Physics) Date: 03/04/2025 - 03/05/2025 Location: Moscow, Russia.