Microscopes 101
Examples of Early Microscopes (16-1700s)
Oculars: 10x
Body Tube: conduct light
Arm: carrying
Nosepiece: rotate lenses
Objective lenses:
◦ Scanning: 4x
◦ Low: 10x
◦ High: 40x
◦ Oil Immersion: 100x
Base: carrying
Illuminator: light
Diaphragm: ↑ or ↓ light
Condenser: Focus light
Stage: Hold slide
Stage clips: Secure slide
Stage knobs: Move slide
Coarse adjustment: First
focus (scanning or low)
Fine adjustment: Final
focus (high)
Electron Microscopes
Transmission
◦ Thinly sliced
◦ Like Compound Light
◦ 2 dimensional
Allon Weiner, The Weizmann Institute of Science
Scanning
◦ Whole
◦ Like Stereomicroscope
◦ 3 dimensional
William Crochot, Dartmoth Electron Microscope Facility
Safety & Care
DO
Report damages
Adjust light
Clean lenses
Turn light off
Point 4x down
Cover
Carry with 2 hands
DON’T
Put eyes directly on
oculars
Wrap cord around
base
Use coarse focus
above low power
Leave slides on stage
Be afraid to ask for
help/questions
How do I work this thing?
Slide on Stage
Scanning/ Low Lens
Coarse Adjustment
Nosepiece
High Lens
Fine Focus
Handling Slides Properly
Mini Lab & Practice
Your cells are showing…..
Directions
1.
Obtain the following items:
1. Microscope (remove cover)
2. Slide
3. Cover Slip
4. Cotton Swab
2. One volunteer will rub the cotton swab on the inside of his or her cheek for at
least 10 seconds
3. Smear the cotton swab on to the center of the slide for about 4 seconds to get
the cells on the slide.
4. RAISE YOUR HAND to receive a drop of methylene blue solution
5. Gently place a cover slip on top (to cover the stain and the smeared cells)
6. Begin using your microscope beginning on the LOWEST objective lens
1. Scan the stage using the adjustment knobs until you locate your cells
2. Once located, increase magnifications to the next objective lens
3. Continue to focus on your cells until the image is crisp!
4. Repeat until you reach highest objective (BUT NOT OIL IMMERSION)
• Clean up your station and store microscope properly!
Cleaning Slides
•Slides are GLASS
•Use EXTRA CAUTION when handling
•Cover slips are GLASS
•Extremely thin and difficult to see if
dropped
•Breaks EXTREMELY easily
•Use alcohol wipe to remove dust and
oils from fingers
•Dry using Kim-tech tissues ONLY
•Carefully return to storage