1. The Compound Light Microscope

2. Parts of the Microscope 1. Ocular lens: eyepiece (10x magnification) First lens First lens 2. Arm: connects base and body tube Must hold arm while carrying microscope Must hold arm while carrying microscope 3. Course Adjustment knob: roughly focuses object Used to find specimen Used to find specimen

3. Parts of the Microscope 4. Fine Adjustment Knob: small knob Finely focuses specimen Finely focuses specimen Used after object has been found Used after object has been found 5. Power Cord: must be wrapped around arm after use 6. Nosepiece: revolving; holds 3 objective lens

4. Parts of the Microscope 7. Objective Lens: second lens Scanning lens (4x), RED Scanning lens (4x), RED Low power (10x), YELLOW Low power (10x), YELLOW High power (40x), High power (40x), Oil immersion (100x), WHITE Oil immersion (100x), WHITE

5. 8. Stage Clips: holds slide in place 9. Stage: flat plate where the slides are placed 10. Diaphragm: regulates the amount of light exposed to the specimen Parts of the Microscope

6. 11. Condenser Lens: focuses light on specimen 12. Power Switch: turns light on and off 13. Base: support of the microscope Parts of the Microscope

7. Field of View The total area visible through the ocular lens. The total area visible through the ocular lens. The higher the magnification, the smaller the field of view. The higher the magnification, the smaller the field of view. Scanning: 40xLow Power: 100xHigh Power: 400x

8. Calculating total magnification Total Magnification = ocular lens x objective lens For example, if the 40x objective is in place the total magnification would be 400x (10*40=400).

9. Drawings PENCIL!  Drawings in PEN are UNACCEPTABLE! PENCIL!  Drawings in PEN are UNACCEPTABLE! Do not forget TOTAL magnification Do not forget TOTAL magnification

10. Focusing the Microscope Locate the slide specimen at scanning power. Locate the slide specimen at scanning power. Then move the area to be viewed to the center of the field of view. Then move the area to be viewed to the center of the field of view. Make sure the slide is in perfect focus at scanning power before moving up to low power. Make sure the slide is in perfect focus at scanning power before moving up to low power. Turn your objective without moving the slide or stage. Turn your objective without moving the slide or stage. You will slightly adjust the image at the next objective. You will slightly adjust the image at the next objective. At high power use only the fine focus knob and do not turn it more than 1/2 turn. At high power use only the fine focus knob and do not turn it more than 1/2 turn.

11. Rules to Remember Always carry with one hand on arm and one on base of the microscope. Always carry with one hand on arm and one on base of the microscope. Use a slide and cover-slip. Use a slide and cover-slip. Clean Up: Always return to scanning (lowest) power. Always return to scanning (lowest) power. Always lower stage all the way. Always lower stage all the way. Unplug, wrap cord and cover. Unplug, wrap cord and cover.