February 27, 2009--Down periscope!

Scientists at Vanderbilt University have built the smallest periscope yet made—about the width of a human hair.

The device, known as a mirrored pyramidal well, uses pyramid-shaped cavities molded into silicon that are then coated with a reflective layer of gold or platinum.

When a tiny object is placed inside the well and viewed through a microscope, the observer can see several sides of the object at the same time.

For example, the image above, released on Tuesday, shows a single grain of sunflower pollen from five different angles.

Scientists are already using the wells to study the structure and behavior of living cells in 3-D.

These tiny tools are much cheaper to make than traditional forms of 3-D microscopy, researchers say. The wells can also reduce the amount of damaging ultraviolet light needed to track fluorescent molecules in cells, a popular technique in gene studies.

(Related: "'Brainbows' Illuminate the Mind's Wiring.")

"This could easily become as ubiquitous as the microscope slide and could replace more expensive methods currently used to position individual cells," team member Ron Reiserer said in a statement.

—Victoria Jaggard