The Microscope and all information about it

all info about microscope

1. The Microscope
Lab 1
Dr.Shahin H.Mustafa
16.9.2025

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

3. Copyright © The McGraw-
Hill Companies, Inc.
Permission required for
reproduction or display.
3
Scale

5. Body Tube
•The body tube holds the objective lenses
and the ocular lens at the proper distance

6. Nose Piece
•The Nose Piece holds the objective lenses and
can be turned to increase the magnification

7. Objective Lenses
•The Objective Lenses increase magnification
usually consist of (4x ,10x, 40x, 100x)

8. Stage Clips (slide holder)
•The clip hold the slide/specimen in place on
the stage.

9. Diaphragm (condenser)
•The Diaphragm controls the amount of light
on the slide/specimen

10. Light Source
•Projects light upwards through the diaphragm,
the specimen and the lenses
•Some have lights, others have mirrors where
you must move the mirror to reflect light

11. Ocular Lens/Eyepiece
•Magnifies the specimen image

12. Arm
•Used to support the microscope when carried.
Holds the body tube, nose piece and
objective lenses
Carry it with 2 HANDS…one on the arm
and the other on the base

13. Stage
•Supports the slide/specimen

14. Coarse Adjustment Knob
•Moves the stage up and down (quickly) for
focusing your image

15. Fine Adjustment Knob
•This knob moves the stage up and down
SLIGHTLY to sharpen the image

16. Base
•Supports the microscope

17. 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”

18. 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 (if it’s a mirror…don’t stand
in front of it!)
•Use fine adjustment to focus

19. The four stage process of using the oil immersion
lens:
1.Focus very carefully with the 40x objective over
the specimen on the slide.
 
2.Rotate turret half way so that the 40x and 100x
objectives straddle specimen.
3.Apply a small drop of oil directly on the slide over
the specimen.
4.Rotate 100x objective into the immersion oil.
*Three important rules attend the use of this lens:
1.Never use an oil immersion lens without the oil.
2.Never get oil on any other lens.
3.Clean up all oil when finished.

21. Copyright © The McGraw-
Hill Companies, Inc.
Permission required for
reproduction or display.
21
Types of Microscope
•many types
–bright-field microscope
–dark-field microscope
–phase-contrast microscope
–fluorescence microscopes
1. Compound Light Microscope
1
st
type of microscope, most
widely used
light passes through 2
lenses
Can magnify up to 2000x

22. 2. Electron Microscope
–Used to observe VERY small objects: viruses, DNA,
parts of cells
–Uses beams of electrons rather than light
–Much more powerful
•wavelength of electron beam
is much shorter than light,
resulting in much higher
resolution

23. 3. Transmission Electron Microscope (TEM)
–Can magnify up to 250,000x

24. 4. Scanning Electron Microscope (SEM)
–Can magnify up to 100,000x

25. Thank you