Science meets art in large rainbow installation at Amsterdam's main train station to celebrate IYL 2015

On 11 December 2014 a large public artwork at the monumental Amsterdam Central train station saw first light, in the form of a rainbow that is projected on the large arch construction that spans over the platforms. The project, called Rainbow Station, constitutes a unique collaboration between world-renowned Studio Roosegaarde, astronomers from Leiden University and optics researchers from North Carolina State University. The core technology of the installation is a patterned liquid crystal grating that creates a curved spectrum that follows the shape of the roof, and is extremely efficient over the entire visible wavelength range. The rainbow will be visible once a day for the duration of 2015, the International Year of Light.

Impression of the Rainbow Station art installation at the Amsterdam Central station. Credit: Studio Roosegaarde.
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Impression of the Rainbow Station art installation at the Amsterdam Central station. Credit: Studio Roosegaarde.

To celebrate the 125th anniversary of the Amsterdam train station, Studio Roosegaarde, which is famous for its innovative light artworks, was commissioned to create an installation that celebrates both the beautiful historic steel construction and modern technology. The Studio's vision for the Rainbow Station project was to create a rainbow with genuine colors by dispersing the light from a white light source, instead of projecting an image of a rainbow. The obvious choice for a dispersive element was a grating, but regular gratings can only produce straight spectra.

Daan Roosegaarde comments:

When we started the Rainbow Station project, everybody told me that it couldn't be done. Until I met these astronomers.

Dr. Frans Snik and Dr. Michiel Rodenhuis of Leiden University are both working on new astronomical instruments to study exoplanets (planets around other stars than the sun). Snik adds:

We are developing new technology to be able to directly image exoplanets, as their signals can be more than a billion times fainter than the light from their parent stars. And once we see such planets, we want to analyze their light to find out what their atmospheres are made of. It turned out that our astronomical technology could also be applied to create a rainbow at the Amsterdam train station.

The Leiden group collaborates intensively with Dr. Michael Escuti, Associate Professor at the North Carolina State University research group that pioneers patterned liquid crystal optics and systems. For the Rainbow Station they designed a modified polarization grating, which is a kind of geometric phase hologram, yielding a spectrum following the exact shape of the arch at Amsterdam train station. Escuti:

Thanks to multiple layers of liquid crystals, this grating is so efficient that it actually includes many more colors than our typical smartphones and TVs can produce, or that our digital cameras can capture. With our technology we were also able to ensure that 99% of the light goes into the rainbow, and not anywhere else.

In addition to state-of-the-art technology, the Rainbow Station is intimately linked to forefront astronomical science. Snik:

Astronomers have used spectra for more than a century to determine temperatures and compositions of stars. For us, the rainbow is a symbol for understanding the universe. Now we are also performing spectroscopic observations of planets around stars. In the foreseeable future we will even be able to investigate whether life is present on such planets! To enable this, we are now building the largest optical telescope ever (the European Extremely Large Telescope), that has a diameter that is almost exactly the same as the diameter of the arch at Amsterdam Central station: 39 meters.

The Rainbow Station installation will produce a rainbow every day in 2015, just after sunset. But, like a real rainbow, its appearance is unpredictable and lasts only a few minutes.

 

About Leiden Observatory

Leiden Observatory at Leiden University (the Netherlands) is a world-leading astronomical institute. Its instrumentation group develops technologies and instruments for current and future telescopes including new approaches to directly image planets around stars other than the sun. These technologies are also applied to other scientific challenges such as the characterization of dust particles in the Earth's atmosphere.

About IYL 2015

The International Year of Light and Light-Based Technologies (IYL 2015) is a global initiative adopted by the United Nations (A/RES/68/221) to raise awareness of how optical technologies promote sustainable development and provide solutions to worldwide challenges in energy, education, agriculture, communications and health.  With UNESCO as lead agency, IYL 2015 programs will promote improved public and political understanding of the central role of light in the modern world while also celebrating noteworthy anniversaries in 2015—from the first studies of optics 1,000 years ago to discoveries in optical communications that power the Internet today. The IYL Global Secretariat is located at the Abdus Salam International Centre of Theoretical Physics (ICTP).

The Founding Partners of IYL 2015 are the American Institute of Physics (AIP), the American Physical Society (APS), the Deutsche Physikalische Gesellschaft (DPG), the European Physical Society (EPS), the Abdus Salam International Centre of Theoretical Physics (ICTP), the IEEE Photonics Society (IPS), the Institute of Physics (IOP), Light: Science and Applications, the lightsources.org International Network, 1001 Inventions, The Optical Society (OSA) and the International Society for Optics and Photonics (SPIE).

Patron Sponsors include Bosca, the International Association of Lighting Designers (IALD), Royal Philips Lighting, Thorlabs and UL.

Contacts

Frans Snik
Leiden University
snik@strw.leidenuniv.nl

Lidi Brouwer
Studio Roosegaarde
lidi@studioroosegaarde.net

Michael Escuti
North Carolina State University and ImagineOptix
mjescuti@ncsu.edu

John Dudley
Steering Committee Chair
International Year of Light and Light-based Technologies 2015
president@eps.org

Joe Niemela
Global Coordinator (IYL Secretariat)
International Year of Light and Light-based Technologies 2015
light2015@ictp.it