47
IX73
Problem
Cause
Remedy
Page
a) The bulb does not light.
Power cord of the TH4 is unplugged. Plug the power cord into a power
outlet.
62
Main switch of the TH4 is not “ I ” ON. Set the main switch to “ I ” (ON).
14
Bulb is burnt out.
Replace the bulb.
52
b) The bulb lights but the field of
view is dark.
Lamp voltage is too low.
Increase the light intensity to an opti-
mum voltage.
14
Condenser is not well positioned.
Adjust the condenser height until the
field iris diaphragm image is formed
in the specimen plane.
28
Light path selector knob is set for the
left side port light path.
Change the light path.
15
Too many filters are used.
Reduce the number of filters to the
minimum required.
26
Stage center plate is engaged in the
light path.
Move the stage and place the speci-
men again.
18
Field iris diaphragm is not opened
wide enough.
Open the field iris diaphragm suf-
ficiently.
27
c) Field of view is obscured or not
evenly illuminated.
An objective that falls outside the
condenser’s illumination range is
used.
Use a condenser that matches the
objective.
28
Field iris diaphragm is not properly
centered.
Center the field iris diaphragm cor-
rectly
28
Field iris diaphragm is stopped down
too far.
Open the field iris diaphragm suf-
ficiently.
27
A filter is stopped in an intermediate
position.
Set the filter at the appropriate posi-
tion.
26
d) Dirt or dust is visible in the field of
view.
Dirt/dust on the specimen.
Clean thoroughly.
6
Dirt/dust on the eyepieces.
Dirt/dust on a mirror unit.
Dirt/dust on the optical element.
Condenser is not correctly positioned
and the frost filter Ø45 mm (45FR) or
filter is focused.
Adjust the condenser height until the
field iris diaphragm image is formed
in the specimen plane.
28
e) Image glares.
Condenser is raised too high.
Lower to the proper position.
28
Aperture iris diaphragm is stopped
down too far.
Open the aperture iris diaphragm.
30
Under certain conditions, performance of the microscope may be adversely affected by factors other than defects. If problems
occur, please review the following list and take remedial action as needed.
If you cannot solve the problem after checking the entire list, please contact your local Olympus representative for assistance.
7
TROUBLESHOOTING GUIDE
