From Washington Post on 5 Feb. 90 via Dallas News Paper Scientist' experiments focus on making better microscope
Scientists have achieved the first step toward the invention of an entirely new kind of microscope that they predict could be able to see objects as small as the individual molecules in a living cell.
While the electron microscope can see molecules, it will not work on living subjects at normal temperatures and pressures.
The new procedure, called "molecular exciton microscopy," promises to do this because it uses a modified form of ordinary light. The smallest object visible with a light microscope is roughly the size of the shortest wavelength of visible light, which is blue and measures about 400 nanometers (a nanometer is a billionth of a meter).
This is small, but still so big that a single ray illuminates manymolecules at one time, masking differences. The new method, reported in the Journal of Science by Aaron Lewis of Hebrew University in Jerusalem and Raoul Kopelman of the University of Michigan and their colleagues, squeezes light waves into far smaller dimensions.
They did it by shining light through a funnel with an extremely tiny tip. When photons, particles of light, reach the tip, they are absorbed by a crystal of anthracene. Inside the crystal, the photons become excitons (a combination of an electron and a "hole," an electrically charged void). Excitons are far, far smaller than an atom. As they emerge from the tip of the funnel, they are reborn as photons.
