1. The Microscope

2. A Microscopic History

3. 1590 - Hans and Zaccharias Janssen discovered that lenses in a
tube made objects appear much larger.
1609 - Galileo created a better instrument that could focus.
1674 - Anton Van Leeuwenhoek builds an even better microscope
and is the first to see bacteria.

4. Anton Van Leeuwenhoek

5. The Microscope
Parts and Functions

6. Labeling the Microscope

7. A
The Eyepiece
• A lens that magnifies the image made by the
objective lens.

8. B
Coarse Adjustment Knob
• moves the body tube up and down to focus the
image

9. C
Fine Adjustment Knob
• used to make fine movements of the body tube
to sharpen the image

10. D
Objective Lenses
• These are the lenses that provide for the magnification
of the image.
• There is a high powered lens and a low powered lens
that are held on a turret or nosepiece.

11. E
The Stage
• This is where the slide is held so that it can be viewed.
• There are stage clips on the stage that hold the slide
in place.

12. F
The Arm
• This supports the body tube.
• One hand must be placed here to carry the
microscope.

13. G
The Base
• Supports the microscope
• When moving the microscope, one hand must
be underneath the base.

14. H
The Mirror
• This directs light up through the hole in the
stage (diaphragm) through the slide and the
objective lenses.

15. The Diaphragm
• Controls the amount of light that passes
through the slide and lenses.
• Can be twisted to increase or decrease the
width of its opening

16. Terms

17. Power of Magnification
• The relative enlargement of an specimen seen
through a microscope.
• Can be calculated - Power of the Eyepiece Lens X
Power of the Objective Lens

18. Inversion
• An image appears upside down through the
eyepiece.
• When the slide is moved to the right, it appears
in the eyepiece to move to the left.
• When the slide is moved upwards on the stage,
it appears to move to the bottom of the view.

19. Working Distance
• The distance between the objective lens and
the glass slide.
• The higher the magnification, the less distance
between the two.

20. Field of Vision
• The surface area of the slide that can be seen
through the microscope.
• This decreases with increased magnification.

21. For Homework
• Label the parts of the microscope
• Take a look at the website online at
http://www.emsb.qc.ca/marymount/index.htm
• Study for a microscope parts quiz on Friday,
Sept. 9th (Day 6 last period).