Theoretical error analysis of the sampling moiré method and phase compensation methodology for single-shot phase...

Area of Science:

• Optical Metrology
• Precision Measurement
• Phase Analysis

Background:

• The sampling moiré method offers rapid, single-shot phase measurement for small displacements.
• Accurate phase measurement is crucial for micro-displacement analysis.
• Mismatches in grating pitch can introduce errors in sampling moiré techniques.

Purpose of the Study:

• To theoretically analyze phase errors in the sampling moiré method due to linear intensity interpolation with mismatched grating pitches.
• To develop an effective phase compensation methodology to mitigate these errors.
• To validate the compensation method's effectiveness for accurate single-shot phase analysis.

Main Methods:

• Theoretical analysis of phase error in sampling moiré.
• Development of a phase compensation algorithm.
• Numerical simulations to demonstrate compensation effectiveness.

Main Results:

• Periodic phase error is proportional to the square of moiré fringe spatial angular frequency.
• The proposed compensation methodology effectively reduces periodic phase error.
• Simulations confirm accurate single-shot phase analysis even with pitch mismatch.

Conclusions:

• The developed phase compensation methodology enhances the accuracy of the sampling moiré method.
• This technique enables precise small-displacement measurements even with imperfect grating pitch matching.
• The findings are significant for applications requiring high-accuracy, rapid phase measurement.