Probe and Other Microscopies

The history of twentieth-century microscopy is often told as a transition from imaging with light (focused using glass lenses) to imaging with electrons (focused using magnetic lenses). In that story, electrons are simply particle-waves, which act like photons but have a much higher frequency and therefore better theoretical resolution (see chapters on transmission electron microscopy, scanning electron microscopy, and lithography). Even in the 1930s, though, researchers saw that electrons could image surfaces in ways not analogous to light. Such techniques developed and diffused slowly, despite achievements such as the first images of individual atoms. In the 1980s, though, one variant - the scanning tunneling microscope - caught on and led to the invention of the atomic force microscope and its relatives. These “probe” microscopes are now as common as electron microscopes. Their success has catalyzed the union of materials research and the life sciences that accelerated at the turn of the twentieth century.