High-quality images – Electron microscopes produce highly detailed images of structures which are of high quality, revealing complex and delicate structures. Electron microscope is a major capital investment and is not needed for the laboratory diagnosis of most infectious diseases. The major limitations of this microscope are as follows:
In an ordinary microscope, the glass lenses bend (or refract) the light beams passing through them to produce magnification. In an electron microscope, the coils bend the electron beams the same way.
Apart from Microbiology, electron microscopy have a diverse range of applications in many different fields such as technology, industry, biomedical science, and chemistry. In pathology, it is used to examine microscopic features of different diseases including tumors.
Electron microscopy can be used to observe biofilms, but only after dehydrating the specimen, which produces undesirable artifacts and distorts the specimen.
One big advantage of light microscopes is the ability to observe living cells. It is possible to observe a wide range of biological activity, such as the uptake of food, cell division and movement.
Because optical microscopes are limited to the wavelengths of visible light, they can only offer limited magnification (around 1,500 x) and cannot go beyond around 200 nm resolution laterally and 600 to 700 nm axially. In comparison, SEMs are capable of much greater magnification and higher resolution.
Advantages of electron microscopy Magnification and higher resolution – as electrons rather than light waves are used, it can be used to analyze structures which cannot otherwise be seen. The resolution of electron microscopy images is in the range of up to 0.2 nm, which is 1000x more detailed than light microscopy.
What are the advantages of electron microscopes over optical microscopes? - They have a higher resolution and are able to magnify things up to 2 million times. -Light microscopes only magnify up to 1000-2000 times.
Optical microscopes use photons or light energy, while electron microscopes use electrons, which have shorter wavelengths that allows greater magnification. 6. Overall, electron microscopes deliver a more detailed image compared to optical microscopes.
Electrons have much a shorter wavelength than visible light, and this allows electron microscopes to produce higher-resolution images than standard light microscopes. Electron microscopes can be used to examine not just whole cells, but also the subcellular structures and compartments within them.
Advantage: Light microscopes have high magnification. Electron microscopes are helpful in viewing surface details of a specimen. Disadvantage: Light microscopes can be used only in the presence of light and have lower resolution. Electron microscopes can be used only for viewing ultra-thin specimens.
Electron Microscope Disadvantages The main disadvantages are cost, size, maintenance, researcher training and image artifacts resulting from specimen preparation. This type of microscope is a large, cumbersome, expensive piece of equipment, extremely sensitive to vibration and external magnetic fields.
A microscope is an optical instrument having one or more lenses system which is used to get a clear magnified image of minute objects or structures that can’t be viewed by the naked eyes.
Microscopy can simply be understood as the ‘use of microscope’. Microscopy can be defined as the scientific discipline of using microscopes for getting a magnified view of objects that can’t be viewed by naked eyes.
In the 1 st Century AD, the Romans invented the glass and used them to magnify objects.
Magnification is the process of producing an enlarged image of a specimen by using a lens system. In a microscope, magnification can be computed by calculating the magnification power of the eyepiece by the magnification power of the objective in use.
In a simple light microscope, a thin specimen containing a slide is placed on the stage of the microscope.
Broadly parts of a microscope can be studied in 2 groups; optical parts including lenses and light source, and structural parts including head, base, arms, and joints. Modern microscopes have additional electronics and display devices.
A simple microscope is a type of microscope that uses a single lens for magnification. It uses a single convex lens of a small focal length for magnification. In general, its magnification is about 10X. Its magnifying power (m) is given by;
Electron microscope is a major capital investment and is not needed for the laboratory diagnosis of most infectious diseases. The major limitations of this microscope are as follows: It is expensive, requires a large space in the laboratory, and is highly sensitive equipment.
Magnification and higher resolution –Electron microscopes provide an image resolution in the range of up to 0.2 nm. An electron microscope can achieve magnification in excess of 100,000x compared with 1000X magnification with light microscopy.
Like any ordinary microscope, the electron microscope also uses a light source, a combination of lenses to produce a magnified image, however, this vary slightly as compared to ordinary light microscope. Source of light: The source of light is replaced by a beam of very fast-moving electrons.
There are 3 sets of electromagnetic lenses in an electron microscope as compared to two in light microscopes. In addition to the condenser and objective lenses, a third projector lens is also present.
In an electron microscope, the coils bend the electron beams the same way. Image viewing and recording system: The magnified image of the specimen is formed as a photograph (called an electron micrograph) or as an image on a TV screen.
In an ordinary microscope, the glass lenses bend (or refract) the light beams passing through them to produce magnification.
The specimen suitable for electron microscopes should be very thin (20-100 nm thickness) so the bacterial cells and any other biopsy materials should be slice into thin layers. The general flow of sample preparation is as follows: