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Here you'll find explanations and definitions of key technical terms from the fields of optics, scanner technology, laser technology and laser processing.
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see offset error
Skew error is tilting of the image field axes compared to the ideal axes.
What causes skew error ?
Skew error is caused by imprecise bonding of the mirrors or incorrect skew compensation.
Ideally, both image field axes should be perpendicular or parallel to the beam entrance axis. Tilted axes distort the rectangular image field into a parallelogram.
Analog controled systems can compensate skew via a motion of the other axis. The specification is the angle between the actual and theoretical axis in mrad.
Remedy
Skew error can be eliminated by applying image field correction (e.g. with CorreXionPro).
The step response time is the time interval required to execute a jump over a specified distance.
Detailed description
For an abrupt change to a new set position, the scanners need a certain time until the actual position matches the set position. Here, time is also required for waiting until the mirrors have settled and remain within a specified precision level.
SCANLAB specifies step response times at 1% of full scale and 10% of full scale for a precision level of 1/1000 of full scale . Specialized systems might require more revealing step response time specifications.
Hard jumps are not recommended for vector tunings; instead, a defined speed and a jump delay should be used.