Earth in a DropletAnya AnimeshAward: Top 100
School: ridge high school For my photo, I used the principle of refraction to capture an image of the Earth through a droplet. To create the droplets, I used a mixture of water and glycerol, since water alone did not form perfect spheres while falling due to relatively weak intermolecular forces between the water molecules. The glycerol increases these forces, and thus surface tension of the drops, helping them resist deformation while falling. Since the refractive index of the water-glycerol mixture is significantly higher than that of air, when light enters the droplet, it slows down, allowing the drop to act as a convex lens. Convex lenses are thicker at the center and thinner at the edges, causing them to converge incoming parallel rays of light to a focal point. In the photo, the focal point is between the camera and the droplet, and the background is parallel to the drop to prevent the image from being distorted. To capture the entire planet in the drop, I placed the background at a distance more than two times the focal length of the lens, creating an inverted and smaller image of Earth. Another phenomenon I was able to capture in the image was the dispersion of light in the larger droplet. As the white light enters the drop's curved surface, shorter wavelengths, like blue, slow down and bend more sharply than the longer wavelengths like orange and yellow, causing the colors to fan out into a small spectrum around the drop. 
|
|