4.4 Troubleshooting
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4.4.4 When Image is not Shown on Screen
If an image does not appear on the screen or if it is difficult to focus the image, check the
following.
(1) Is a specimen loaded? Is the specimen at the exchange position? Are the accelerating
voltage and emission current normal? Is either SE (secondary electron) or BSE
(backscattered electron) selected as a detector? Is the probe current set too low?
See <3.3.2 Setting the Accelerating Voltage and Filament Current>.
See <3.5.1 Selecting a Detector>.
See <3.10.2 Probe Current Settings and Image Quality>.
(2) Set contrast at maximum.
(3) Open the objective lens movable aperture (set it to the 0 position). If an image appears,
perform mechanical axial alignment and aperture alignment adjustments on the objective
lens movable aperture.
See <3.4.2.2 Axial Alignment Items in Detail>.
(4) If an image fails to appear in Step (3) above, perform a beam alignment.
See <3.4.2.2 Axial Alignment Items in Detail>.
(5) On Operate menu, set the Filament Image mode. If a round image appears off center on
the screen or the circle is chipped, re-adjustments should be performed.
(6) If the BSE option is selected, is the detector properly inserted? Pull out the specimen stage
and verify that the BSE is inserted on the underside of the lens.
If image signals are not displayed at all and the screen fails to become bright even when the
Brightness knob is turned to a maximum position, the problem may be that the PC screen is not
set properly. It should be noted that the screen on the personal computer has the following
default settings:
(Specified using Screen Properties and Setting)
Color palette: Full color (approximately 16,000,000 colors)
Desktop: 1280 x 1024 pixels
Refresh rate: 60 Hz or 75 Hz (monitor-dependent)
If the problem still cannot be resolved, call the service engineer.