The crystals on the surface of an emery board, as seen without (top) and with (bottom) the GelSight paint (Image: Micah Kimo Johnson)
Typically, if someone wishes to obtain three-dimensional images of micrometer-scale objects, they need to use a device such as a confocal microscope or a white-light interferometer. Such equipment is big, expensive, and often has to be mounted on a vibration-free table. Even then, it can take up to a few hours to get the finished images. Scientists at MIT’s Department of Brain and Cognitive Sciences, however, have created a system that can obtain the same kind of images almost instantly, using a soda can-sized sensor and a sheet of rubber. It’s called GelSight.