THE ORIGIN OF SCANNING ELECTRON MICROSCOPE
A typical scanning electron microscope has a magnification range of about 15x to 200,000x and a resolution of 5 nanometers. It is an electron microscope that has a very high energy beam of electrons and a raster scan pattern.
It contains a general information about surface topography,electrical conductivity, and a very high composition. The first image was first taken by a scientist known as Max Knoll, he actually took an image of a silicon steel that has property of an electron contrast.
Then in 1965, was further developed by a professor known as Charles Oatley in the Cambridge scientific company.
X rays can also be detected in an equipped scanned electron microscope. It can only be able to detect X rays if it has X ray spectroscopy, wavelength spectroscopy, and energy dispersive spectroscopy. It has the ability to image very large materials and a small area of a specimen. It also have a sharpmode that can be used to measure the composition and property of a specimen.
There are different types of SEM, depending on their properties. We have the environmental {SEM} and conventional {SEM}.
The conventional scannned electron microscope must be imaged under a vacuum for it to be effective and sharp. Samples that contain a very high amount of vapour and frozen oil bearing rock should be dreid up before being placed under a scanned electron microscope.
Environmental scanned electron microscope was first developed commercially in the 80’s. It is used in an environment that has a low pressure and a very high relative humidity. The first set of this electroscope was first released in 1988 in the United states by an electroscope based corporation.
It is very useful when used for metallic and non metallic materials. Environment scanned electroscope can be used to image or perform X- ray microanalysis and non conducitve specimens. Forensic analysis can also be performed on this electroscope.
With the technological advancement of this age, scanned electron microscope have being upgraded with the best technology materials you can ever think of. It can also only be measured by two methods known as photometric stereo and photogrammmetry.
The images under this electroscope is out of this world, as it is accompanied with a nice artificial colour.
This two types of scanned electroscope i mentioned above are very important, as they have a very high resolution ability.