Microscopy is a technique used to visualize structures or objects of very minute magnification. The invention of microscopes has revolutionized science, medicine, technology and other areas where microscopic structural examination is required for betterment. It was possible to identify microbes like bacteria, fungi, protozoans etc. which are the causes of epidemic diseases in medicine, some of them were found to yield human beneficial products like insulin, antibiotics etc.
Types of microscope:
Simple microscope is a just microscope with a single magnification lens like 10x. It is used to visualise any small objects invisible to direct naked eye.
Stereoscopic dissecting microscope: This microscope is commonly used to study and to identify the opaque objects. It is generally used for low power observation, dissection, etc. Its magnifying power varies from 4x to 40x or even 60x. It has two objectives and two eyepieces which help to make a 3D image of an object.
Compound microscope: Compound microscope is the most commonly used microscope it has 2 or 3 objectives and a single eyepiece. The magnification power ranges from 5x to 8x, 10x to 15 x with the magnification of the objectives that ranges between 10x or 40x. It is used to examine semitransparent and translucent objects, or part of objects in the form of thin slides.
Phase contrast microscope: Phase contrast microscope is commonly used to study biological tissues and specimens. It is also known as one of the most important tool in medical research. It is generally used to study the specimens that are colorless and transparent and usually difficult to distinguish from their surroundings such specimens and objects are commonly known as phase objects. All phase contrast microscope are not same but they work on the same principle and have five eyepieces of different magnification that includes 10x, 20x, 40x, 100x and Bright Field (BF).
The electron microscope: The electron microscope is used to study a variety of biological and non-biological products such as cells, microorganisms, biopsy sample, metals, crystals and large molecules. It is one of the important tools for biological and medical sciences as it magnifies the image of an object by 10,000,000x. In electron microscope two types of lenses “electrostatic” and “electromagnetic” are used to control the beam of electron which helps to illuminates the specimen and produces its magnified image. Electron microscope is of five different types:
1. Transmission electron microscope (TEM) 2. Scanning electron microscope
3. Reflection electron microscope 4. Scanning transmission electron microscope
5. Low-voltage electron microscope