Kuo I A, Glaeser R M
Ultramicroscopy. 1975 Jul;1(1):53-66. doi: 10.1016/s0304-3991(75)80007-6.
Specimen damage resulting from inelastic scattering is one of the factors that limits high-resolution electron microscopy of biological specimens. We have, therefore, sought to develop a method to record images of periodic objects at a reduced electron exposure in order to preserve high-resolution structural detail. The resulting image will tend increasingly to be a statistically noisy one, as the electron exposure is reduced to lower and lower values. Construction of a statistically defined image from such data is possible by spatial averaging of the electron signals from a large number of identical unit cells. In this paper, we have first investigated the theory pertaining to the attainable resolution as a function of the electron exposure, the magnification, and several other relevant parameters. In addition, we report experimental results obtained with a commercial image intensifier and with nuclear track photographic emulsion, both of which are highly sensitive recording devices. Usable images can be recorded and processed at exposures in the image plane as low as 10(-3) electron/micron2 (1.6 x 10(-14) coulomb/cm2).
非弹性散射导致的标本损伤是限制生物标本高分辨率电子显微镜观察的因素之一。因此，我们试图开发一种方法，在降低电子曝光量的情况下记录周期性物体的图像，以保留高分辨率的结构细节。随着电子曝光量降低到越来越低的值，所得图像将越来越趋于成为统计上有噪声的图像。通过对来自大量相同晶胞的电子信号进行空间平均，可以从这些数据构建统计定义的图像。在本文中，我们首先研究了与可达到的分辨率相关的理论，该分辨率是电子曝光量、放大倍数和其他几个相关参数的函数。此外，我们报告了使用商业图像增强器和核径迹照相乳剂获得的实验结果，这两种都是高灵敏度记录设备。在图像平面曝光低至10^(-3)电子/微米²（1.6×10^(-14)库仑/厘米²）时，可以记录和处理可用图像。
