Sample Calibration Target
Selecting and Using Calibration Targets
The following guidelines are intended to help you select a calibration
target for measurements.
- Any dot grid type of target can be used
for calibration.
- The calibration target should be chosen
to fit the accuracy requirements of the application.
- In general, the calibration target should
have a 5 to 10 times greater accuracy than the tolerance of the part
to be measured.
- Chrome dots on a ceramic surface (or other
diffuse surface) can be used for front-lit applications.
- Chrome dots on a glass surface can be
used for back-lit applications.
- Calibration targets are available from
many commercial suppliers. Two examples are shown below.

The example on the left is from Dot
Vision: https://www.dot-vision.com.
The example on the right
is from Edmund Optics: https://www.edmundoptics.com/f/diffuse-reflectance-grid-distortion-targets/13635.
- Target tolerances for commercially available
grid calibration targets are typically +/-0.001mm (+/-1 micron), which
is sufficient for most high-accuracy applications.
- Paper targets with lower accuracy
can be printed from the Sysmac
Studio Calibration
Plate Print Tool and can be used to test the calibration
process. The dots in the 15 x 15 grid are nominally 4 mm apart.

Calibration Guidelines
- It is very important that the dots on
the calibration target be placed at exactly the same distance from
the camera that the part will be. If the system is not calibrated
with the target at the same distance, the measurements will read larger
or smaller than the real-world dimensions of objects in the field
of view.
- If it is not possible to set the dots
of the calibration target at the same plane as the part, you can apply
a scale factor determined by measuring a “golden part“ to adjust the
readings.
