Waters GCT Premier Operator's Manual page 303

EI Tune tab parameters: (Continued)
Parameter
Beam Steering
Focus 1
Focus 2
Focus 3
Filament and Emission are readback fields.
Note:
Description
The beam steering applies a voltage to one side of
the focus lens and reduces voltage on the lens'
other side. This redistribution of voltage to change
the lens angle effectively steer a beam left or right.
The readback from one side of the focus 1 lens
appears in the left field of the two Beam Steering
fields. The readback for the other side of the focus
1 lens appears in the left Focus 1 field. The read-
back values appear in red.
Voltage on the first focusing lens.
Voltage on the second focusing lens.
Voltage on the third focusing lens.
The Tune window tuning controls B-25