Contributions to Quantitative Electron Microscopy

Abstract

The effect of various parameters on contrast in an electron microscope image is analyzed and a simplified formula tested. The dependence of contrast on the weight per unit area, voltage, and aperture is in good agreement with the theory of electron scattering. The observed dependence of screening angle on atomic number deviates from the theory for higher atomic numbers, but carbon and elements of comparable atomic number are not affected. The application of quantitative electron microscopy to biological objects can be considered workable to ±10%.