Throughout this issue of the Archives the reader will find the results, mainly in the form of micrographs, of morphologic studies of ocular tissues obtained with the electron microscope. The techniques employed in electron microscopy differ considerably from those of light microscopy. For the proper appreciation of these results obtained with this instrument some knowledge of the methods used in specimen preparation is required. The purpose of this presentation is to outline some of the principles, materials, and techniques of electron microscopy.
The resolution of the average human eye (i.e., the closest two points or lines can be together and still be perceived as separate) is considered to fall in the range of 0.1-0.2 mm. (100μ-200μ). This inherent limitation of the eye is overcome by use of magnifying lenses which refract light to "spread" these two points apart, so that intermediate points or lines may be distinguished as separate. Glass