Instruction manual

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surface of the specimen. At a shorter WD, higher resolution is attainable.

At a longer WD, a larger tilt angle and a greater depth of focus is attainable.

When a WD is selected from pull-down menu, the objective lens current is adjusted in order to

focus an image at the specified WD.

This function is useful for:

1) To obtaining focus of the specimen surface quickly after introducing a specimen.

2) Focusing the specimen at a specific WD.

For X-ray analysis, the same WD (15 mm) should be used in order to maintain the

X-ray take-off angle. In that case, set WD from pull-down menu and adjust Z position of the

specimen stage to focus the image. (Use focusing operation only for fine adjustment.)

The shortest usable WD is changed according to present accelerating voltage. The possible

The WD range indication shows the present available value.

The following table shows relation of WD and resolution, depth of focus or specimen tilting

angle.

Short WD Long

Resolution High Low

Depth of focus Shallow Deep

Specimen tilt angle Small Large

Specimen

Objective lens