Of course, like many newer things, this idea belongs to the Japanese, in this case to a group of scientists from the Graduate School of Life Science and Systems Engineering of the Kyushu Institute of Technology (KIT), led by Shuji Hayase.
What the scientists did was using some of the optical fiber’s properties to generate electricity from light. They formed dye-sensitized solar cell layers concentrically around a 3.5cm glass rod, as you can see in the image above.
The cell is formed this way: a layer of titanium dioxide and a sensitizing pigment, a porous Titanium layer as the anode, a porous layer containing an iodine solution and other electrolytes, and a layer of Platinum and Titanium, serving as cathode. The entire solar cell is then covered with Titanium, excepting for the ends of the glass rod, that have to admit and release light.
The efficiency of this fiber-optic solar cell can be increased either by increasing the fiber length, or by reducing its diameter, said Hayase. He says it could go to about 10%.
Also, the cell is aimed at using near-infrared light, spectrum to which classic solar cells are not so sensitive.