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Catching the Light from Distant Stars: The Subaru Observatory Optics
At an altitude of 4200m above sea level, the Japanese “Subaru”
large optical-infrared telescope atop Mauna Kea on the island of
Hawaii is home to Canon ultra-high performance lens
technology.
With an 8.2-meter diameter, the telescope’s main mirror is the
largest in the world, and is equipped with an optical system that
creates an image at the principal focus – an unheard-of feature
in large reflecting telescopes. And it is Canon lens technology
which made the principal focus correction optical system
possible. Canon developed this system using the concept of
“smaller and lighter” in order to solve the problem of how to fit
it onto the principal focus of the telescope – a feat otherwise
impossible using conventional optical design. Indeed, compared
to the original design specifications, Canon succeeded in
making the system 70% smaller and 50% lighter than it would
have turned out otherwise
http://software.canon-europe.com/files/documents/EF_Lens_Work_Book_6_EN.pdf
