Researchers at an I.B.M. laboratory have captured a three-dimensional image of a biological virus using, for the first time, a technique that has some similarity to magnetic resonance imaging, a tool routinely used by physicians to peer inside the human body.

Although the technique is akin to M.R.I., the results were 100 million times better in terms of resolution with the new technique, magnetic resonance force microscopy, or M.R.F.M. The team of researchers, based at the computer maker’s Almaden Research Center in San Jose, Calif., reports in the The Proceedings of the National Academy of Sciences that they have captured a 3-D image of a tobacco mosaic virus with a spatial resolution down to four nanometers.

Techniques like atomic force and scanning tunneling microscopes have provided images of individual atoms. (An atom is about one-tenth of a nanometer in diameter). But these techniques are more destructive of biological samples because they send a stream of electrons at the target in order to get an image. And these microscopes cannot peer beneath the surface of the Lilliputian structures. The researchers said that many of their ideas had evolved from earlier work on atomic force microscopes. “The one thing that has always intrigued me, is, can we take the same idea and do it in three dimensions?” said Daniel Rugar, an I.B.M. physicist who helped design the first M.R.F. microscope in 1993. “We’d like to be able to take pictures of atomic structures like molecules. That’s been our motivation.”

The development of M.R.F.M. as a three-dimensional microscope actually began in 1991 with publication of a speculative paper by a theoretical physicist, John A. Sidles, who was then searching for new tools to help design drugs to combat the AIDS virus. After reading about atomic force microscope research at I.B.M., Dr. Sidles, who is a professor of orthopedics at the University of Washington School of Medicine, called Dr. Rugar and proposed a related tool that measured minute magnetic fields to construct images of biological structures.