Microscopes

1
Microscopes
2
Some Microscope Parts
3
Some Microscope Parts
(a.k.a body tube/keeps eyepiece at correct
distance from objective)
(lens to see through Magnifies 10x)
NOSE PIECE
(select objective lens)
(Carry microscope)
(lenses close to object/specimen Magnifies 10x,
20x, or 40x)
STAGE
(holds slide)
(sharpens focus)
(Lifts or lowers stage to produce a focused
image)
(focuses/condenses light on specimen)
(Carry microscope)
4
Iris Diaphragm (open 1/close 5)

• Can be used to increase contrast (close 5)
• Or increase amount of light (open 1)

Stage Clips
Diaphragm
Diaphragm lever
5
Magnifying Power

• Eyepiece x objective lens TOTAL magnification
• LOW POWER 10x X 10x 100x
• HIGH POWER 10x X 43x 430x
• correct units for a microscope micrometer (µm)
• 1 µm (1/1000) mm

6
KEEP IT CLEAN!

• When to use

Objective lens Glass slides Cover slips Condenser Eye piece
Lens tissue
Slide tissue
X
X
X
X
X
7
Sequence for Viewing

1. plug in turn on
2. find object in LOW POWER
3. focus with coarse adjustment adjust light
   (light 1 lets in the most 5 least)
4. center object (still in low power)
5. turn to high power objective without changing
   focus
6. re-adjust light
7. sharpen focus with fine adjustment

8
PARFOCAL

• ability for the microscope to remain in focus
  when objective lens is changed

Low power
9
Make a Wet Mount
10
Store your Microscope Properly

1. Take slide OFF
2. Put lower power above stage
3. Roll nosepiece up (old) Stage down (new)
4. Turn OFF light
5. Wrap cord around scope

11
How not to break the microscope

• Always carry the microscope with 2 hands, one
  hand under the base the other grasping the arm.

12
Discussion and Summary
Appears in the Eyepiece
H
A
F
13
What a microscope does to an image

• It _____________________
• It turns it _______________
• _____________________

Magnifies
Upside down
Backwards
14
As the power of the microscope

• Magnification increases
• The field of vision
• The depth of field
• Amount of light passing through the lens system

DECREASES
15
0.2mm
0.1nm