1. Introduction to Microscopy

2. Objectives Learn to use a compound microscope correctly. Diagram the path of light through a compound microscope. Name major parts of a compound microscope. Identify three basic morphologies of bacteria.

3. Size in Microbial World

6. Magnification Refraction (bending) of light as it passes through the lens produces magnified image Two sets of lens contribute to total magnification Four objective lenses: 4x (scanning), 10x (low power), 40-45x (high power), 100x (oil immersion). Ocular lens: 10x

7. Resolution Wavelength of light used Resolving Power = 2 x numerical aperture

8. Qualities of a Good Image Brightness - related to NA. Focus - related to Focal Length. Resolution - related to NA & λ. Contrast - related to illumination (can be improved)

9. Focusing and Iris Diaphragm