microscopes. eyepiece contains the ocular lens nosepiece holds the high and low-power objective...
DESCRIPTION
What’s my power? To calculate the power of magnification, multiply the power of the ocular lens by the power of the objective.TRANSCRIPT
Micros
copes
EyepieceContains the ocular lens
Nosepiece Holds the high and low-power
objective lenses; can be
rotated to change
magnification.
Objective Lenses
Magnification ranges from 10X to 40X
Stage Clips
Holds the slide in place
StageSupports the slide
being viewed
Light SourceProjects light
upwards through the
diaphragm, the specimen, and
the lenses.
BaseSupports the microscope
DiaphragmRegulates
the amount of light on the specimen
Fine Adjustment
KnobMoves the
stage slightly to sharpen the image.
Coarse Adjustment
KnobMoves the
stage up and down for focusing.
ArmSupports
upper parts of the
microscope, used to carry
the microscope.
Fill in the table
• Our ocular lens has a magnification of 10X.What are the powers of magnification for
each of the objectives we have on our microscopes?
Fill in the table on your worksheet.
Objective lens Total Magnification
4X
10X
40X
Comparing Powers of Magnification
We can see better details with higher the powers of magnification, but we cannot see as much of the image.
Which of these images would be viewed at a higher power of
magnification?
Handling The Microscope
• When you need to move the microscope from one place to another, use both hands!– One hand should be under the base and the other
one on the arm.• Do not touch the lens with your fingers. • Use ONLY lens paper to clean the glass—
tissue, TP, paper towels with scratch the lens!
Using the microscope
• Make sure the power is on the lowest magnification (4X).
• Place the slide on the stage and use the stage clips to hold it in place.
• Adjust the diaphragm—to let more or less light travel through.
Using the Microscope
• Use the coarse adjustment knob to move the stage and get the specimen in focus.– You can use the fine adjustment (very slightly) to
sharpen the focus.
• Adjust the diaphragm as needed to change the amount of light if more or less contrast is needed.
• Turn to the 10X lens and use ONLY the FINE adjustment to focus.
• If needed, you may change your magnification to high power (40X).– NEVER use the coarse adjustment knob on
medium or high power objective lenses!!!!
Microscope Use
• To use the microscope place a glass slide on the stage of the microscope, and turn the revolving nosepiece until the low power (4X) objective is in line with the eyepiece.
• Use the coarse adjusting knob to turn the objective lens close to the stage.
• Slowly move the coarse adjusting knob until the specimen becomes focused.
• Once your specimen is found on low power you can move the objective to 10X for more magnification, and then 40X.
Microscope Use
• When your objective lens is on high power you only use the fine adjusting knob to focus.
• Stage clips may or may not be used to hold your slide on the stage.
• The diaphragm allows you to adjust the light allowed onto the stage.
Microscope Care
*When done using a microscope move the objective lens to low power and place the cover over the microscope.
• If you move a microscope use both hands and be careful.
• Make sure to unplug your microscope when done.
• Use lens paper to clean off dust from a slide of microscope lens.