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Received an order of special large core fibers for the Subaru Telescope

February 12, 2014

Fujikura Ltd. (Yoichi Nagahama, President and CEO) received an order of 200 kilometers fibers for the Subaru Telescope from Tokyo University.

The new project named SuMIRe began in order to make a three dimensions map of dark matters and dark energy, the keys to explore the origin of the universe, galaxies and stars and to foresee the future of the universe, and to discover the secret of history of the expansion of the universe. This project will set a spectrograph that can observe thousands of far galaxies in the Subaru Telescope, operated by the National Astronomical Observatory at the peak of Mauna Kea- 4200 meters above the sea level- in Hawaii, and will approach the origin of the universe by watching galaxies that are several billions light years away.

Because the Subaru Telescope needs to observe thousands lights of astronomical image, the wavelength of the light is from 380nm to 1300nm, through its main lens at the same time, thousands fibers need to bring those lights to the spectroscope that is dozens of meters away with low loss. The spectrograph provides many sample data to find when and where lights of astronomical image come from. In addition, in order to receive slight lights efficiently, the large core fiber requires high numerical aperture (NA≥0.22).

To this date, it has been difficult to realize large core fibers with low loss and high numerical aperture from short wavelengths to long one. Fujikura lowers structural defects of silica glasses that have absorption loss in the ultraviolet region, by optimizing fiber structures and production methods. As a result, it successfully developed large core fibers that have the field's lowest loss as 38dB/km (typical value) at 395nm, which is one of the important wavelengths for observing, maintaining low loss around 1300 nm region.

Various evaluation by the customer showed that our low loss large core fibers have outstanding characteristics compared to competitors' fibers for astronomical observation. Thanks to this result, we received the order from Tokyo University. These fibers are expected to be applied for applications that require low loss characteristics in wide wavelength range such as spectroscopic analysis.

Fujikura will contribute to development of society by applying optical fiber technologies developed in the field of telecommunication to scientific technologies such as spectroscopic analysis equipment etc. and medical devices.

Special large core fibers used for the Subaru Telescope

Special large core fibers used for the Subaru Telescopev