Electronic Read-Out with an Integrating Intensifier System

Image tube read-out of an electron microscope image must utilize integration of the image, as does photographic recording, if a high signal to noise ratio is to be obtained. The integration time must be of sufficient duration so the noise, or the statistical fluctuations in the number of electrons in an image element is smaller than the signal or contrast of the element with respect to the surrounding region. In our application we are primarily concerned with a system which will allow storage and data processing of the image information contained in the output. An integrating video system can also be used to advantage for visual observation and for focusing, since it provides image intensification at a higher signal to noise ratio than does a conventional intensifier system.