SCHOTT solutions no. 2/2013 > Fiber Optics

Photo: Celsius

Clockwork Communicator

The makers of Celsius X VI II mobile devices have an unusual dream: a solely mechanical cell phone. In their newest model, SCHOTT has helped them enable an imaging system that works entirely without digital screens.

Thomas H. Loewe

It is the ultimate fusion of communication technology and micromechanics: a cellular phone by Celsius X VI II. The innovative French brand has been combining modern mobile telephony with prestigious mechanical watchmaking since 2008. ”I had the idea during a flight from Paris to Hong Kong,” says company founder Thomas Pruvot. Frustrated at losing the time display when he had to switch off his cellphone, he imagined adopting a mechanical solution – a cell phone merged with a tourbillon watch and an exclusive butterfly winding mechanism. The most recent model includes an innovative Image Guiding System developed in collaboration with specialists from SCHOTT Lighting and Imaging.
The OptiC GMT from the French brand Celsius X VI II is a very special cell phone indeed. This stylish device combines mobile communications technology with the traditional art of watchmaking. Multicore light rods from SCHOTT make it possible to show the date and time even without electricity. Photo: Celsius
”At first glance, the date numbers of the OptiC GMT appear on a small pixelated screen, as if emerging from nowhere,” says Pruvot. But in fact, they are inscribed on a rotating cylinder nestled at the heart of the micromechanical clockwork inside the phone. “There is no digital imaging involved at all,” explains Martin Cramer from SCHOTT’s Engineering and Development team.
Instead, light is guided onto the inscribed cylinder through glass rods and cones and back out again. The imaging system relies solely on mechanical and optical components – with multicore light rods custom developed by SCHOTT.

But what looks like a single piece of glass is actually an optical feat made of multiple fibers. Cramer: ”Each rod consists of over 1,000 single strands of glass as thin as a hair.” Together, they form an imaging solution that can be molded into the desired shape. This way, the cone geometry used for both the date and time zone displays also has a magnifying effect. And because each optic fiber transmits just a single pixel of light, the combination of all fibers enables the system to transmit a crispy clear image from within
the phone.

With every new model Celsius develops, they are one step closer to realizing their dream. A dream that embraces a concept, which is still impossible today but may come true in future: an entirely mechanical cell phone. Pruvot: ”With SCHOTT’s help, we have come a little closer to making it happen.”