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Either click the auto-focus button or select Auto Focus on the View menu to execute auto
focusing.
Figure 4.2.9-4 Coarse Focusing (Auto-focusing in Progress Screen)
The precision of auto-focusing can be affected by the surface structure of the specimen.
Auto-focusing will not operate properly if the specimen surface contains few minute structural
features, its contrast is low, or the specimen is liable to become charged. In such cases,
manual focusing should be employed.
4.2.10 Selecting an Observation FOV
An FOV can be selected by two methods:
・
Searching for a target FOV by turning the XY motion knobs (see Section 3.2.1) on the
manual stage. (For the manual stage)
・
Searching for a FOV by mouse operation on the observation screen. (For the motor drive
stage)
・
Searching for a target FOV by using the image shift (see Section 4.2.10
2.
).
(1) Manual Stage
To move the FOV extensively, use the XY motion knobs for the manual
stage. To move it finely, use the image shift. When moving the FOV for a high-magnification
observation (x5,000 or higher), it would be difficult to move it to a target location by using the
XY-motion knobs on the specimen stage, in which case the use of image shift is
recommended. Image shift provides a maximum motion size of ±50
μ
m, which makes it a
suitable tool for performing fine adjustments for conducting a high-magnification observation
at x5,000 or higher.
Summary of Contents for TM3000
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