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Comparison Measurements
Comparison measurements rely on the known dimensions of an object
that has been set in the field of view either by the manufacturer or by the
probe or takes advantage of known dimensions within the frozen image.
The MViQ processor uses these known dimensions as a reference scale for
measuring an unknown target. You can take comparison measurements
on a frozen (non-3DPM) image or on a recalled image that was saved in
Comparison measurement mode.
Making a Comparison Measurement
Use the head guard or attach any standard forward-view or side-view
tip to the probe. Select the Field of View (FOV) for your OTA from the soft
key or the touch screen. This allows the system to improve accuracy by
compensating for the OTA's optical distortion. If FOV is not known consult
Appendix B
. Position the camera for maximum accuracy, by making the
surface to be measured appear perpendicular to the probe view. The
target and known object should both be in the same plane at the same
distance from the camera and as close as possible while fitting them both
fully into the image.
1
– Select
Comparison
to launch the measurement mode. Begin by
selecting the measurement type.
Click here to view a description of each
measurement type.
2
– A reference of known length must next be input by placing two cursors
and defining the reference length.
3
– The reference length cursors remain.
4
– Arrange measurement cursors to determine the unknown dimension.
In this case, the system is performing a Length measurement.
5
– Select
Add Measurement
to input a New Reference Dimension, Add
another measurement (up to 5), or change the active measurement (by
selecting Next Measurement).
6
– Once a reference length is defined, a circle of known diameter can be
displayed on the image by selecting this option. The circle gauge may be
used as a “go/no-go” gauge when its diameter is set to a defect size limit.
