1. Microscope History and Development
Field of view and Magnification

2. Robert Hooke
In 1665, the English physicist Robert Hooke looked at a sliver of cork through a microscope lens and noticed some "pores" or "cells" in it.
Hooke was the first person to use the word "cell" to identify microscopic structures when he was describing cork.

3. Antique microscopes

4. Early Microscopes - Anton Van Leeuwenhoek
The father of microscopy, Anton Van Leeuwenhoek of Holland ( ).
Anton Van Leeuwenhoek was the first to see and describe bacteria (1674), yeast plants, the teeming life in a drop of water, and the circulation of blood corpuscles in capillaries.

6. Robert Brown
In 1820 was using a more advanced microscope with 2 lenses and was able to see that there were smaller parts within a cell
He was the first to use the term “nucleus” to describe a round object in the center of the cell

7. The Cell Theory All living things are made up of one or more cells
The cell is the functional unit of life.

8. Technological Advances in Microscopes

9. Compound Light Microscopes
Uses light
Has two lenses
Magnification limited to 2000x (400x at LHHS)

10. Transmission Electron Microscope (TEM)
Uses beams of electrons
Magnification of x
Has two limitations:
Good only for thin specimens
Only dead cells can be observed

11. Scanning Electron Microscope (SEM)
Electrons are reflected from the surface of the specimen
Produces a 3-d image
Good for the thicker specimens
Lacks the magnification and resolution of the transmission electron microscope

12. Magnification Magnification = Objective lens X Ocular lens
(4x, 10x, 40x) (10x)

13. Calculating the size of a specimen
binder

14. Calculating the size of a specimen Example under med. objective
Object size = Size of field of view Number of objects across field of view
Object size = 1.72 mm
Object size = 0.1 mm