1. The Microscope

2. Definition
A compound microscope is an optical instrument used to magnify and resolve fine detail within a transparent specimen. It has two separate lenses:
(1) The objective lens and (2) the eyepiece

3. Function of Microscope Parts

4. Eyepiece
The topmost optical lens system, also called the ocular. This is where the eye is positioned to view the object. Magnifies 10X
Eyepiece

5. Pointer
Used to locate an object being viewed under the scope. Turning the eyepiece changes the pointer.
Pointer
(inside)

6. Body Tube
This is where the rays of light are bent so that the object being viewed is enlarged by the scope
Body Tube

7. Arm
Supports the body tube and the objectives. Used to carry the microscope
Arm

8. Low Power Objective
Magnifies 10x and is found above the specimen. Always begin focusing under low power
Low Power
(smallest
objective)

9. Medium Power Magnifies 25x. Use second after low power. Medium Power
(middle sized
objective)

10. High Power Objective
Magnifies 65x and is used last for greatest detail
High Power
(largest
objective)

11. Coarse Adjustment Knob
The larger set of knobs used for coarse focusing under low power
Coarse
Adjustment
Knob

12. Fine Adjustment Knob
Smaller set of focusing knobs used to control fine focusing under medium and high power
Fine
Adjustment
Knob

13. Base
Supports the scope. Also used to carry the scope along with the arm
Base

14. Stage
Flat area that supports the microscope slide
Stage

15. Stage Clips
Hold the slide in place
Stage Clips

16. In-Stage Condenser
Focuses and concentrates the light coming through the stage so that the object is correctly illuminated
Aka aperture
In-Stage
Condenser

17. Diaphragm
The rotatable disc located beneath the stage that controls the amount of light entering the in-stage condenser
Diaphragm

18. Nosepiece
Supports the revolving nosepiece
Nosepiece

19. Revolving Nosepiece
Supports the objectives and is used to change from low to high
Revolving
Nosepiece

20. Resolution Vs. Magnification

21. Resolution
The ability of a microscope to distinguish two objects as being separate

22. Magnification
The ability of a microscope to make objects appear larger.

23. Resolution is more important than magnification!

24. Magnification

25. The magnification of the low power objective is 10x

26. The magnification of the medium power objective is 25x

27. The magnification of the high power objective is 65x

28. The magnification of the eyepiece is 10x

29. To find the Total Magnification you must Multiply
Low Power X Eyepiece = Total magnification Under low power 10 x 10 = 100

30. Carrying a Microscope

31. 1. One hand is placed around the arm and the other is placed under the base.

32. 2. Always hold in an upright position

33. 3. The stage clips should be turned inward

34. 4. Eyepeice at “home position” on low power.

35. 5. Body tube is in “home position” (all the way up)

36. 6. All slides have been put away and are no longer on the stage.

37. 7. Cord is unplugged and wrapped around the base

38. Procedures for Focusing the Microscope

39. 1. Put the microscope on low power and turn the stage all the way down

40. 2. Place the microscope slide on the stage and secure with stage clips

41. 3. While looking through the eyepiece, turn the coarse adjuster toward you until the object comes into focus

42. 4. Turn the objective to medium power and refocus while looking through the eyepiece using the fine adjuster

43. 5. Turn the objective to high power and refocus while looking through the eyepiece using the fine adjuster

45. (whole thing)
Body tube
eyepiece
pointer
Nosepiece
Arm
Revolving Nosepiece
Stage Clip
Objectives
(opening) In-Stage
Condenser
Stage Stop
Stage
Coarse
Adjustment
Diaphragm
Light
Fine
Adjustment
Power Switch
Base

46. Lab Safety: What NOT to do!