Microscopy || Types Of Microscope

 Types Of Microscopes:

 

Microscope 

Microscopy is a technical field of using a microscope to view objects and the areas of objects that cannot be seen with the naked eye

Microscopy is the science of investigating small objects and structures using a Microscope.

Microscope means being invisible to the eye unless aided by the microscope.

Variables Used In Microscopy:

1) Magnification:

The magnification or linear magnification is defined as the ratio of the image size to the object.

Both Magnification and magnifying power or angular magnification is the angle subtended by the object and the image

The magnification of objective lens is called linear magnification. While the Magnification of Eyepiece is called Angular Magnification.

So, The total magnification of the compound microscope is the product of both the linear magnification of objective lens and angular magnification of eyepiece.

               Total Magnification = Magnification Of Eyepiece X  Magnification of Objective.

2) Resolving Power:

It may be defined as the ability of microscope to distinguish two objects that are closer together.

The limit of resolution is defined as the minimum distance between the two points that allow the discrimination as two separate points.

It is inversely proportional to the limit of resolution

3) Focal Depth:

The focal depth (depth of focus) is the range of distance for which the object is imaged with an acceptable sharpness on the image plane.

The focal depth is proportional to the spatial resolution of a microscope and to the square of magnifications, and inversely proportional to the numerical aperture angle.

4) Focal Length:

The distance from the center of the lens to the focal point is called focal length.

Because the image occurs on the other side of the lens from where the object is positioned, the focal length for convex lenses has a positive sign.

Concave Lenses--where the faces of the lens curved inward--have negative focal length

5) Lens Strength:

Focal length is important because it determines the lens strength, which is an indication of how much the lens enlarge the image.

Lens Strength is calculated by dividing the number one by the focal length--taking the inverse of the focal length.

6) Ocular Lens:

The focal length of an objective is the distance from the lens to the point where parellel rays of light passing through the lens converge

Types Of Microscopes:

Depending upon the principle on which magnification is based;

There are two types of Microscopes.
1) Light Microscope
2) Electron Microscope

1) Light Microscope:

Light Microscopy in which magnification is obtained by a system of optical lenses using light waves.

Types Of Light Microscopes:
1) Bright Field Microscope
2) Dark Field Microscope
3) Phase Contrast Microscope
4) Fluorescence Microscope

2) Electron Microscope:

Electron Microscope is used when the maximum revolution is required, and when a living state can be ignored.

Types Of Electron Microscope
1) Transmission Electron Microscope (TEM).
2) Scanning Electron Microscope (SEM).