Wei-ming CHENG, Lin-zhi SUN. Improvement of positioning precision for precise stage with compensation[J]. Optics and precision engineering, 2008, 16(5): 884-888.
Wei-ming CHENG, Lin-zhi SUN. Improvement of positioning precision for precise stage with compensation[J]. Optics and precision engineering, 2008, 16(5): 884-888.DOI:
Improvement of positioning precision for precise stage with compensation
System errors should be removed to improve the precision of a precise positioning stage because of their influence to affection the precision. As a mean of effective and lowly-costing compensation
the reverse compensation could be mainly used to eliminate the errors. According the principle of the reverse compensation
the error curve of a stage is reversed to match negatively the original one that was measured and drawn before
so that the largest proportion of error
which is just the system error
could be separated and removed. The positioning stage described in this paper has a 2-layer structure
in which the lower is macro-stage and the upper is micro-one. The macro-stage is driven by precision ball lead-screw and positioned by optical grating. And the micro-stage is driven by PZT and uses an inductance as sensor. The positioning precision of the macro-stage is measured as 17.4μm before compensation
which is
obviously
too big to conform to the requirements of micro-stage’s moving. The precision is improved to 1.3μm after using the principle described above
then the macro-stage satisfies the need of precision positioning. As the same
the precision of micro-stage is improved from 137.6nm to 22.2nm
which accomplishes nano-scale positioning successfully. The experiment shows that the reverse compensation is effective to eliminate the system errors
and on the other hand
it also shows that the method is not very good at removing the random errors because it is impossible to find the reverse curve to match.