Microscopy: The History Of Microscope

723 Words2 Pages

MICROSCOPY
Microscopy is the technique to examine minute objects through microscope which can not be seen by naked eye. (1)
HISTORY OF MICROSCOPY
SCIENTIST YEAR CONTRIBUTION
Hans and Zacharias Janssen 1590 Created first microscope
Robert Hooke 1667 Published micrographia
Anton van leeuwenhoek 1675 Used microscope with one lens. He was first to observe bacteria.
Joseph Jackson lister 1830 Discovered that weak lenses in combination provide clear magnification
Richard zsigmondy 1903 Invented ultra microscope
Frits xernike 1932 Invented phase contrast microscope
Ernst ruska 1938 Invented electron microscope
Gerd binning and Heinrich rohrer 1981 Invented scanning tunneling microscope (2)
MICROSCOPIC TECHNIQUES
There are many microscopic …show more content…

This technique has a very little contrast which is mostly provided by staining specimens.
• LIGHT MICROSCOPY
It is the technique that uses visible light as a source of illumination to view small objects which are in finer detail than the ability of naked eye.
HISTORY
Antony van leewenhoek invented simple microscope in 1670 which was able to magnify upto 200x so he was the first person to see individual cells.
Another scientist Robert Hooke further advanced the compound microscope by adding some additional instrumentation such as stage, an illuminator and coarse and fine adjustment knobs.
WORKING PRINCIPLE
Compound microscope contain two lenses in series
• The objective lens
• Eye piece lens
The objective produces magnified real image of the object which is further magnified by the ocular lens to obtain final virtual image of the specimen. (3) (10)
NUMERICAL APERTURE
Numerical aperture is defined as the diameter of the objective lens in relation with focal length
n.a = n sin 0
TOTAL MAGNIFICATION
The total magnification is the product of ocular magnification and objective magnification
Mt= MOB X MOC
USES
• Easy to use
• reasonably priced
• live samples can be

More about Microscopy: The History Of Microscope

Open Document