2.3.9

2.3.9.1Optics Tab

The Optics tab is for setting operating condition of the electron optical column.

(1)ELECTRON BEAM Window

Sets electron optical system conditions.

Fig. 2.3-40 Setup Window – Optics Tab

(a)Vacc

Sets and accelerating voltage. This function is equivalent to the ELECTRON BEAM window on the Operation Panel.

(b)Emission Current

Indicates the present emission current.

(c)Filament

Changes the filament current and adjusts the temperature to which the filament is to be heated. The filament current should be adjusted to a point slightly below the saturation point for the emission current.

The Auto Filament Saturation (AFS) function automatically sets an appropriate filament current. AFS can be run in three modes, low, medium, and high, and can be used for the following purposes:

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