The origin of the microscope was given that the ancients knew that looking through curved mirrors or glass spheres with water, made small things see with magnification. It is then when the first decades of the seventeenth century began to carry out tests with lenses in order to obtain a greater magnification of the objects. For this they were based on the first instrument made with lenses that had great success "the telescope " used for the first time in astronomical purposes by Galileo in the year 1609.
At the beginning of the 20th century the manufacture of this was concentrated mainly in Germany and in the following years phase contrast, fluorescence, holography, interference, X-rays, ultraviolet light, methods with electrons and protons were developed. Computerized microscopes were also developed for quantification, quantification and three-dimensional analysis, these instruments opened many fields in the area of microscopy. From the year 1660 to the present, the optical microscope has been the fundamental pillar for the study of the invisible. Although, its resolution increased over time with the improvement of the quality of the lenses as well as its power of magnification.
In 1930 the submicroscopic world was expanded with the creation of the electron microscope whose main difference to the optical microscope is the increase of 1000 times more in the magnification phase of the observed material, accompanied by a better resolution capacity generating better definition and magnification in the microscopic world.
There are two types of basic electron microscopes, both were invented at the same time but they fulfill different functions, these are:
- Transmission electron microscope (MET): this is responsible for projecting electrons through a thin layer of material or tissue to be observed, reflecting an image on a phosphorescent screen.
- Scanning electron microscope (SEM): this produces an image that gives the impression of being in three dimensions. This microscope uses three or two points where the electrons of the sample arrive to scan the surface of the specimen to be observed.
Most of the pioneers of electron microscopy in biology are still alive and the most important are: Albert Claude, Earnest Fullam, Don Fawcett, Charles Leblond, John Luft, Daniel Pease, Keith Porter and George Palade.
