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11.
Insert the liner tube into the liner pipe.
12.
Mount the anode by turning it clockwise, and close the electron gun.
13.
Press the EVAC/AIR switch to evacuate the air from the specimen chamber. After
completing the evacuation, The lighting pattern of EVAC LED (blue) changes from
blinking to lighting. In the next step, perform beam axis alignment (see 5.2).
Figure 5.3-11 Replacing the Condenser Lens Aperture (4)
5.4 Objective
Aperture
Replacement
The objective aperture is built into the liner tube. After the system has been in use for about
6 months and it appears that there is image deterioration (an out-of-focus condition), replace
the objective aperture. When replacing the objective aperture, it is recommended that the
condenser lens aperture be also replaced at the same time.
1.
Introduce air into the specimen chamber.
Press the [EVAC/AIR] button to introduce air into the specimen chamber. After
completing the introduction, the lighting pattern of AIR LED (yellow) changes from
blinking to lighting.
2.
After confirming that AIR LED lights yellow, terminate the application program and turn
off the power switch on the right side of the main unit.
CAUTION
: After the system has been in use, the Wehnelt and the anode around the
filament are heated about 90
C. Touching any of them can cause burns.
Before undertaking any filament replacement work, turn off the main unit
and wait at least 30 minutes to allow it to cool down.
3.
Wait for a minimum of 30 minutes, and then open the top cover. Holding onto the lower
part of the top cover with your finger tips, gently lift it.
Liner Pipe
