Citizen debuted the Eco-Drive in 1995 with the Caliber 7878, but it had been evolving the tech since 1976. As opposed to its original Crystron Solar Cell, which was the world’s first commercial analog quartz watch powered by solar cells, Eco-Drive had thinner cells that could accommodate indoor light as well. This was groundbreaking and still feels ahead of its time, since most of us might not necessarily spend a whole lot of time outdoors to charge our timepieces under the sun.
Celebrating 50 years of solar innovation, Citizen has debuted the Eco-Drive Photon, taking inspiration from the double-slit light experiment you may have done in physics class.
A Physics Lesson on Your Wrist
In 1801, British scientist Thomas Young devised the…