6 Setting up the 3D scanner system
3DPIXA
CD40131 Version 1
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6.7.1
Checking the synchronization with target speed
Perform the following procedure to check the synchroniziation between the camera and the
target speed:
1. Place a graph paper on a moving stage in the focus of the 3DPIXA camera.
2. Acquire an image of the moving graph paper.
3. Check the image for distortions of the graphic lines by counting pixels:
Image
Distortion
Cause
No distortion
The moving speed and the
integration time are suitable.
Compression along the moving
direction
The moving speed is too high
or
the integration time is too long.
Stretching along the moving
direction
The moving speed is too low
or
the integration time is too short.
Tab. 18: Examples for images
Count the pixels in the center of the image for an accurate determination.
4. If distortion exists, calculate the new moving speed and/or the integration time as follows:
– Count the number of pixels along the blue and the red arrows.
Example compression: 18 pixels along the blue arrow, 9 pixels along the red arrow
Example stretching: 18 pixels along the blue arrow, 27 pixels along the red arrow
– Multiply the current speed/time with the ratio of red arrow pixels to blue arrow pixels.
Example compression:
9/18 * current moving speed = 0.5 * current moving speed = new moving speed
9/18 * current integration time = 0.5 * current integration time = new integration time
Example stretching:
27/18 * current moving speed = 1.5 * current moving speed = new moving speed
27/18 * current integration time = 1.5 * current integration time = new integration time
5. Set the new moving speed and/or integration time (see chapter 6.10, p. 66).
