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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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Tracking error is the time interval between the set and actual positions when traversing a vector.
What causes tracking error?
Because a scanner's mass inertia hinders it from instantaneously reaching the intended set position, it must accelerate and decelerate. A steady speed is desirable for laser marking, so the servo shouldn't attempt to overtake the set position during vector traversal. Instead, it needs to move at constant speed.
The time interval between the set and actual positions is called tracking error and is essentially independent of vector speed.
The spatial difference, i.e. the lag error, is proportional to speed.
The following applies: lag error = tracking error x speed.
A small tracking lag enables shorter scan delays and is thus advantageous for fragmented marking, but it limits the maximum speed. Depending on the application, a good match might be achievable through various tunings.
Tuning is a particular method of dynamically optimizing the scan system. Here, fine adjustments are applied to the analog or digital servos that determine the scan system's dynamic response to deviations from the set position.
Most tunings are characterized by tracking error and maximum speed. A small tracking error enables fragmented/fine-structured marking, but sharply limits maximum speed. In contrast, higher speeds also increase tracking error.
On analog systems, tuning is directly implemented in the servo electronics. Systems with iDRIVE technology (e.g. intelliSCAN) can internally store up to three tunings. During marking, you can switch between those tunings.
What kind of tunings are available?
Tunings can optimize scan systems to meet diverse requirements, e.g. for vectors, jumps, corner-precision or micro-machining.
The following table provides an overview of the most common tunings:
|(Fast) Vector Tuning||Well-balanced, optimal relationship between all parameters for a wide range of applications||Vector marking|
|Jump-Tuning||Minimal jump times for long jumps||Drilling|
|Sharp Edge Tuning||Low acceleration times, small corner-rounding||
|Micromachining Tuning||Low dither, low line-ripple||Vector marking,
|Line Scan Tuning||Highest line speeds (with higher acceleration time)||USP laser processes|
see Angle Terms