4. Maintenance
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(3)Focusing knob
z Check this knob for any abnormal tightness, play, unevenness, and sound.
(4)XY stage
z Check the stage glass for scratches and contaminants.
z Move the XY stage over the measuring range by hand to check for any abnormal tightness, play,
unevenness, and sound. (Perform the same cheek on the stage by turning the micrometer heads.)
(5)Angle dial
z Loosen the angle dial clamp knob and turn the dial to check for any abnormal tightness, play,
unevenness, and sound.
(6)Field of view
z Look into the eyepiece under contour illumination and check the entire filed of view for
vignetting and uneven illumination.
(7)XY stage feeding accuracy
z This inspection will be affected by the measuring environment, alignment error, and other
adverse conditions. Keeping these factors in mind, check the feeding accuracy by measuring a
workpiece or a standard scale with an appropriate dimension of 5mm.
1. Position a workpiece, for which accurate dimensions are known, on the stage glass and
bring it into focus.
2. Align a measuring point on the workpiece with one of the cross-hairs, according to the
moving direction of the workpiece.
3. Obtain the dimension from the readings on the Micrometer Head. Refer to “3.2.1
Dimensional measurement”.
4. Measure the X- and Y-axis dimensions of the workpiece.
If the difference between the measured and nominal dimensions is less than 5Ǵm (for any 5mm
travel range), the XY stage feeding accuracy is adequate.
(8)Resolution
z Position a workpiece on the XY stage and bring it into focus. Check if any region of the image in
the field of view has poor resolution.
