The substance is called GelSight, and it is a transparent, synthetic rubber, one side of which is painted with a substance that contains flecks of metal. When the painted side is pressed against a surface, it conforms to that surface, showing a detailed image. The gel is attached to a soda-can sized camera that, when the photo is processed, can produce a 3D image of the surface for computer analysis.
GelSight could allow for a more detailed look at the surface of objects that cannot fit under a microscope. The technology has forensic, dermatological and biometric applications. GelSight can help in the identification of the markings on spent shell casings, the identification of cancerous skin growths and detailed fingerprint analysis.