What is Fluid Lensing?


Mapping the closest frontier, our oceans.

Whenever you look through a substance, whether it’s the water in a pool or a pane of old, rippled glass, the objects you see look distorted. For centuries, astronomers have been mapping the sky through the distortions caused by our atmosphere, however, in recent years, they’ve developed techniques to counter these effects, clearing our view of the stars. If we turn to look at the Earth instead of the skies, distorted visuals are a challenge too: Earth scientists who want to map the oceans or study underwater features struggle to see through the distortions caused by waves at the surface.

Researchers at NASA’s Ames Research Center, in California’s Silicon Valley, are focused on solving this problem with fluid lensing, a technique for imaging through the ocean’s surface. While we’ve mapped the surfaces of the Moon and Mars in great detail, only 4% of the ocean floor is currently mapped. Getting accurate depth measurements and clear images is difficult in part, due to how light is absorbed and intensified by the water and distorted by its surface. By running complex calculations, the algorithm at the heart of fluid lensing technology is largely able to correct for these troublesome effects.

You’ve probably noticed these distortions between light and water before. When you look down at your body in a swimming pool, it appears at odd angles and different sizes because you’re looking at it through the water’s surface. When light passes through that surface, it also creates bright bands of light, in an almost web-like structure that you see at the bottom of the pool called caustics. When caustics, are combined with the other distortions caused by water, they make imaging the ocean floor a difficult process. Caustics on the ocean floor are so bright that sometimes they are even brighter than sunlight at the surface!

Continue reading at NASA Ames Research Center

Image via NASA Ames Research Center