5 OPERATION
EM210F-1
5-39
?
The center spot in the diffraction diagram is called as “direct spot” and other
spots are called as “Diffraction spots”.
6.
Depress the MAG1 switch (R1-
②
) to obtain the MAG mode.
7.
Adjust the image brightness using the BRIGHTNESS knob (L1-
⑥
).
A dark field image (Fig. 5.37-c) appears on the screen.
?
Use the SHIFT knobs (L1-
⑧
, R1-
③
) to center the beam if necessary.
5.4.3 Low Magnification Image
This mode is useful when searching the field of view in the wide area and also useful for
searching the field at low magnifications. Since the objective aperture cannot be used in
this mode, the field limiting aperture is used to enhance the image contrast.
5.4.3a
Low magnification image observation
1.
Select “Maintenance” on the “TEN Controller” main menu to display the
“Alignment Panel for Maintenance” screen.
2.
Carry out column alignment (
F
Sect. 5.3.2).
3.
Remove the objective and field limiting apertures from the beam path (
F
Sect. 5.2.9).
4.
Depress the LOW MAG switch (R1-
②
).
5.
Select the desired magnification with the MAG/CAM L knob (R1-
⑤
).
A selected magnification appears on screen.
6.
Adjust the image brightness using the BRIGHTNESS knob (L1-
⑥
).
A dark field image appears on the screen.
?
Use the SHIFT knobs (L1-
⑧
, R1-
③
) to center the beam if necessary.
7.
Perform the current center adjustment (
F
Sect. 5.4.3b).
5.4.3b Current center adjustment
1.
Select “Maintenance” on the “TEN Controller” main menu to display the
“Alignment Panel for Maintenance” screen.
2.
Depress the BRIGHT switch (L1-
⑥
) or turn on “Wobbler-OBJ” on the
“Alignment Panel for Maintenance” screen.
?
The image rotates around a point on the screen. This center is called “Current
center”.
3.
Depress on the BRIGHT TILT switch (L1-
⑥
) or turn on “DEF Select-CLA” on
the “Alignment Panel for Maintenance” screen.
4.
Bring the current center to the screen center using the DEF/STIG knobs (L1-
⑩
, R1-
④
).
5.
Turn off “WOBBLER-OBJ” on the “Alignment Panel for Maintenance” screen.
6.
Carry out the astigmatism correction (
F
Sect. 5.4.4).
