Microscope is chip off the old block.

• Position: Engineering

The development of a super-compact, high-resolution microscope small enough to fit on a fingertip has turned science fiction into reality at the California Institute of Technology, Pasadena. This "microscopic microscope" operates without lenses but has the magnifying power of a top-quality optical microscope, can be used in the field to analyze blood samples for malaria or check water supplies for giardia and other pathogens, and can be mass-produced for around $10.

"The whole thing is truly compact--it could be put in a cell phone--and it can use just sunlight for illumination, which makes it very appealing for Third-World applications," notes Changhuei Yang, assistant professor of electrical engineering and bioengineering who developed the device, dubbed an optofluidic microscope.

The instrument combines traditional computer-chip technology with microfluidics--the channeling of fluid flow at incredibly small scales. An entire optofluidic microscope chip is about twice the size of a dime, although the part of the device that images objects is only the size of Pres. Franklin Roosevelt's nose on that dime.

"Our research is motivated by the fact that microscopes have been around since the 16th century, and yet their basic design has undergone very...