Components and Functions of the Microscope The Vernier Scale: What it is, how to read it How to use a Microscope

1. THE MICROSCOPE Components and
Functions

2. Eye Piece
Body Tube
Limb
Nose Piece
Objective
Lens
Stage Stop
Fine Focus
Course Focus
(Although not
shown!) On/off
switch
Iris Diaphragm/Rheostat
Base
Light
Source
Condenser
Stage

3. THE STAGE COMPONENTS
Mechanical
Stage Control
Vernier
Scale
Apertur
e
Stage
Clip
Stage
Lock
Control

4. FUNCTIONS. Body Tube
Hollow tube
housing eye piece
in top and nose
piece in lower end
Eye Piece
• Contains ocular and field
lens
• Magnifying primary image
formed by objective lens
• Commonly magnify x10

5. FUNCTIONS Limb
Connects base with body
and supports microscope
structure
Nose Piece
In base of body
tube housing &
objective lenses
in rotating turret
Objective Lens
Commonly four housed
within nosepiece:
• x4 Scanning
• x10 Low Power
• x40 High Dry
• x100 Oil Immersion
Stage Stop
Safety feature to
prevent stage coming
into contact with
objective lens

6. FUNCTIONS
Fine Focus
Adjustment
provides subtle
adjustment to
stage height
improving clarity
of image
Course Focus
Adjusts stage height
to provide initial
focusing of the
specimen
Iris Diaphragm/Rheostat
• A lever controlled aperture
that modifies the amount
of light passing through
the condenser
• Some have coloured filters
(e.g. blue to reduce the
amount of red or yellow
Condenser
• Two lens fitted
below stage
• Light is
condensed from
light source
providing a sharp
and bright image
• Adjusts
accordingly
• Image is viewed
upside down and
reversedLight Source
• Bulb controlled by rheostat
(controls amount of power
supply)
• Turn light down prior to
switching off to preserve bulb!
Base
Firmly supports other
components

7. FUNCTIONS OF THE COMPONENTS
OF THE STAGE
Part Function
Stage Clip Holds microscope slide in place
Aperture Window held within the stage
Mechanical Stage • Hole in centre allows light from
condenser to illuminate specimen
• Holds slide in place, facilitate movement
of slide (east-west, north-south)
Mechanical Stage Control Enables the slide holder to be moved left,
right, up or down
Vernier Scale Vertical (X axis) and horizontal (Y axis)
main scales used to relocate a specific
point on the slide
Stage Lock Locking device fixing the stage in place

8. USING THE MICROSCOPE
1. Plug the microscope into the power socket
2. Clean the eye pieces and condenser lens with lint free, lens cleaning tissue
3. Use rheostat to turn the light intensity to the lowest setting to avoid bulb damage
4. Turn on the power switch at the wall and on the microscope
5. Rack down mechanical stage to its lowest point using the course focus knob
6. Select the lowest power objective lens and lock into place using the rotating turret
7. Place prepared slide onto stage and secure with stage clips – ensure slide is
correct way up, frosted edge to the left

9. USING THE MICROSCOPE
8. Before looking into the eye piece, rotate the course focus knob until
the stage is at its highest position
9. Adjust rheostat to a medium setting
10. Adjust height of the sub stage condenser to a few mm below the
stage
11. Using the course focus knob, move the stage downwards until the
image comes into focus
12. Use fine focus to refine detail
13. Adjust condenser and diaphragm accordingly
14. Increase the objective lens power in order and accordingly

10. THE BATTLEMENT TECHNIQUE
This technique is when viewing an object using x100 (oil immersion).

11. THE VERNIER SCALE
First, we need to
look where the 0 is.
We can see here
that it is between
10cm and 10.1 cm.
Because it is in the
middle, you should
use the lower
value, so 10cm.
Next, it needs to
be determined
where the main
scale marries up
with the vernier
scale. Here, the
lines marry up at
2.
Vernier Scale =
10.2

12. THE VERNIER SCALE
The 0 lies between 3
and 4. So, we need
to use the lower
value of 3.
The main scale and vernier
scale marries up at 3.
Vernier Scale = 3.3
** If the 0 falls on a
whole number (i.e. not
in between two values),
then the vernier scale
reading wont be
required (e.g. 34.0)**

13. HAVE A GO…
Vernier Scale =
5.6