VRm AreaScan3D, Руководство пользователя

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Operation
5.3 Positioning the Measured Object
After the sensor has been positioned, the measured object most prob-
ably has to be aligned, too.
Positioning the measured object
1. Use the user software to project a static fringe pattern onto the
object.
2. Position the object so that the predominant or the most undulated
surface structures are aligned perpendicular to the stripes (see
following figure). Aligning those surface structures parallel to the
stripes would lead to larger triangulation angles up to the occur-
rence of shadowing and can also result in artifacts (height peaks)
with strongly reflective surfaces.
ð
A good alignment is given if both wide and narrow fringes deli-
ver a good contrast in the camera image over the entire surface
area and depth range.
3. Depending on surface reflectance and local angles relative to the
sensor, direct reflections of projector light into the camera can oc-
cur. This may result in excessive brightness values and may cause
missing or wrong data at these points.
If this is the case, tilt the object slightly. Keep an eye on the measu-
red surface: it has to stay within the distance range of the central
measuring field.
For further instructions refer to the software documentation on the
provided USB stick.