The study of cells,cellparts and organisms that are too small to be seen with naked eyes using microscopes
Light microscope
Uses light as a source of radiation to form the image of the specimen being studied
Electron microscope
Uses electron as a source of radiation to form the image of the specimen being studied
Types of electron microscopes
Transmissionelectronmicroscope (TEM)
Scanningelectronmicroscope (SEM)
Transmission electron microscope (TEM)
Electron is passedthrough the specimen and allows us to see thin sections of the specimen, and thus the inside of the cells
Scanning electron microscope (SEM)
Electron beam is passed back and forth over the surface of the specimen, and only the reflected beam is observed to obtain a three dimensional appearance
How the light microscope works
1. Substage illumination is the light source
2. Light must come only from substage position
3. Iris diaphragm controls the amount of light reaching the specimen
4. Condenser focuses the light onto the specimen
5. Objective lens collects the light passing through the specimen and produces a magnified image
6. Eyepiece lens magnifies the image formed by the objective lens and focuses it onto the eye
The objectivelens is responsible for both the magnification and resolution of the image
Theeyepiecelensmagnifies but doesnotresolve the image formed by the objectivelens
