Microscope Notes
Parts of the Microscope
Coarse adjustment knob- Focuses the image under low power (usually the bigger knob)
Fine adjustment knob-Sharpens the image under all powers (usually the smaller knob)
Arm- supports the body tube and is used to carry the microscope.
Body tube – connects the eyepiece to the nosepiece (usually moves during focusing)
Eyepiece- the lens you look through (usually at 10X magnification)
Nosepiece- holds all the objectives and it revolves
Base- supports the microscope and used for carrying the microscope.
Stage – used to support the slide
Stage clips- used to hold the slide in place
Diaphragm- Used to regulate the amount of light
Light source- provides light
Low power objective- has the lowest magnification and is the shortest objective
Medium power objective – increases the magnification
High power objective- provides the most magnification and is the longest objective.
Care of the microscope
1. Always carry the microscope with one hand holding the arm and the other supporting the base.
2. Don’t touch the lenses with your fingers
3. Never lower the coarse adjustment knob while looking through the eyepiece.
4. Always focus first with the low-power objective.
5. DON’T use the coarse adjustment knob with medium or high power.
6. ALWAYS leave the microscope with the low power objective in place and the body tube at its
highest position.
7. Cover the microscope.
Using the microscope
1. The microscope should be on a level surface (your desk).
2. Make sure the diaphragm is open and plenty of light comes through.
3. FOCUSING
a. Always start with the low power objective and focus with the coarse adjustment knob.
b. Once you have found and focused on an item, move the slide so the item is in the center of
your field of vision.
c. Rotate the nosepiece so that the medium objective is clicked into place. Do NOT use the
coarse adjustment knob.
d. Focus on the item using the fine adjustment. Move the slide so the item is in the center of
your field of vision.
e. Rotate the nosepiece until the high power objective is clicked into place. Do NOT use the
coarse adjustment knob on high power.
f. Use the fine adjustment knob to focus.
g. If you lose the image going from one objective to the next, do NOT adjust the focus. Go
back to the previous objective and center the item.
Making a wet mount slide
1. Place the item in the center of the slide.
2. Place 1 drop of water on the item.
3. Get a clean coverslip. Be sure to hold it by the edges.
