The parts of the compound light microscope and their main functions.

1. The Light
Microscope

2. Convex Lenses are
curved glass used to
make microscopes
(and glasses etc.)
Convex Lenses
bend
light and focus
it in
one spot.
How a Microscope Works

3. How a Microscope Works
Ocular Lens
(Magnifies Image)
Objective Lens
(Gathers Light,
Magnifies
And Focuses Image
Inside Body Tube)Body Tube
(Image Focuses)
•Bending Light: The objective (bottom) convex lens
magnifies and focuses (bends) the image inside the
body tube and the ocular convex (top) lens of a
microscope magnifies it (again).

4. Body Tube
Nose Piece
Objective
Lenses
Stage
Clips
Diaphragm
Light Source
Ocular Lens
Arm
Stage
Coarse Adj.
Fine Adjustment
Base
Skip to Magnification Section

6. Eyepiece / Ocular Lens
• Magnifies the specimen image
• It is where you look through to view the
object placed on the stage.

7. Body Tube
• It supports the eyepiece and lenses.
• It also maintains the proper distance
between the eyepiece and the objective
lenses.

8. Nose Piece
• It holds the objective lenses and
can be turned to increase the
magnification.

9. Objective Lenses
• It is used to magnify the images of the
specimen to form an enlarged image.

10. Stage Clips
• These 2 clips hold the slide/specimen in
place on the stage.

11. Diaphragm
• It controls the amount of light on the
slide/specimen
Turn to let more light
in or to make dimmer.

12. Mirror
• It reflects light to the lens of
the microscope.

13. Arm
• It is the frame to which the base, body
and stage are attached.

14. Stage
• Supports the slide/specimen

15. Coarse Adjustment Knob
• Moves the stage up and down
LARGER focusing of the image.

16. • This knob moves the stage slightly to
sharpen the image for PRECISION
focusing.
Fine Adjustment Knob

17. Base
• Supports the microscope and is also
used for carrying the microscope.

18. Magnification
• To determine your magnification…you
just multiply the ocular lens by the
objective lens
• Ocular 10x Objective 40x:10 x 40 =
400
Objective Lens have
their magnification
written on them.
Ocular lenses usually
magnifies by 10x
So the object is 400 times
“larger”

19. Caring for a Microscope
• Clean only with a soft
cloth/tissue
• Make sure it’s on a flat surface
• Carry it with 2 HANDS…one on
the arm and the other on the
base

20. Using a Microscope
• Start on the lowest magnification
• Don’t use the coarse adjustment
knob on high magnification … you’ll
break the slide.
• Place slide on stage and lock clips
• Adjust light source/ mirror.
• Use fine adjustment to focus

21. Credits
• You and the Natural World:
Integrated Science by Lilia G.
Vengco and Teresita F. Religioso.
Phoenix Publishing House, Inc.
• Discover Science by Allas, et. al.
Diwa Learning Systems Inc.
• http://www.freeclubweb.com/powerp
oints/science/index.html