In the field of photonics—the science of light generation, manipulation and detection—two companies are working on innovative technologies that hold promise for future uses. Ambient Photonics, in California, was inspired by photosynthesis to develop a solar cell that can generate power from low-level ambient light rather than direct sunlight. These indoor solar cells use a special dye to absorb light and create energy, making them more versatile and efficient than traditional solar panels. Because they are thin, flexible and can be applied to most surfaces, they could potentially replace batteries.