Researchers from the Northwestern University have discovered that the pattern of information written on a Blu-ray disc works very well for improving light absorption across the solar spectrum. Blu-ray discs contain a higher density of data than DVDs or CDs due to smaller pits and lands (0s and 1s). The quasi-random pattern of pits and lands, provides the right texture to improve the cells’ light absorption and performance when transferred to the surface of solar cells.
For solar cells to become more efficient the light has to be scattered more effectively which is achieved by placing a texture on them. Scientists have long been searching for the most effective texture with a reasonable manufacturing cost.
The researchers from McCormick have demonstrated that the texture of a Blu-ray disc gives solar cells the near-optimal surface texture to improve their absorption over the broad spectrum of sunlight. The pattern of the Blu-ray texture was more efficient than a random pattern texture. A random pattern in it’s place worked better than no pattern, but the pattern on Blu-ray discs was proven to be best.
It didn’t matter what kind of Blu-ray disc used, all kinds of discs were tested including action movies, dramas, documentaries, cartoons and black-and-white content. The tests concluded that the video content did not matter.
The researchers wondered why the Blu-ray pattern works so well and conclude that the quasi-random array of pits and lands with feature sizes between 150 and 525 nanometers works quite well for light-trapping applications over the entire solar spectrum.
Therefor it’s expected that Blu-ray patterns could be broadly applied for light trapping in other kinds of solar cells.