X-ray microscopy

The principles and limitations of the chief methods of x-ray microscopy are briefly reviewed in turn: reflection microscopy, contact microradiography, projection microscopy and scanning microscopy. None of the methods as yet surpasses the resolution limit of the light microscope, although all of them approach it more or less closely. Their primary advantage over other microscopical methods is the ability to provide evidence of element distribution, by differential absorption or by characteristic emission. The projection method is proving useful for analysis by microfluorescence as well as by absorption. The scanning x-ray microscope, a developed form of the electron probe microanalyser, has found a wide variety of applications in metallurgy and mineralogy, and to a lesser extent in biology. The present limitations on its performance and the prospects for further development are discussed.