Positional Deviation
Incremental errors in the reading of a displacement sensor occur when internal components shift relative to their calibrated zero point. Gradual changes in temperature or mechanical fatigue cause the glass or metal scale to expand or contract.
Measurement Instability
Cumulative inaccuracies in the reported coordinates result from small changes in the physical mounting of the sensor head. The electronics within the reader head generate heat that may alter the local environment of the scale. Software routines track these changes to prevent the misinterpretation of pixel locations in the resulting image.
When the measured position no longer matches the physical location of the stage, linear encoder drift introduces blurring or geometric distortion in the 3d reconstruction.
Environmental Sensitivity
Control of the ambient temperature within the machine enclosure limits the rate of positional change. A variation of even one degree Celsius is enough to move a high-resolution stage outside its specified tolerance. Closed-loop feedback systems attempt to correct for linear encoder drift by referencing a fixed physical point during the initialization sequence.
Regular calibration against a known standard ensures that the displacement readings remain within the required accuracy for sub-micron inspection tasks. High-precision x-ray systems use linear encoder drift as a metric for the stability of the motion stage over extended operating periods.
