Detection techniques in low-coherence interferometry and their impact on overall measurement accuracy

Area of Science:

• Optical Engineering
• Metrology
• Instrumentation

Background:

• Low-coherence interferometry is vital for contactless 3D inspection of macroscopic objects.
• Accurate interference fringe center detection is critical for measurement precision.

Purpose of the Study:

• To analyze and compare various interference fringe center detection techniques.
• To assess the impact of these techniques on measurement accuracy in low-coherence interferometry.
• To evaluate computational complexity and resistance to optical dispersion.

Main Methods:

• Complex analysis of frequently used fringe center detection algorithms.
• Comparative evaluation based on computational load, accuracy, and dispersion resistance.
• Testing under conditions simulating optical dispersion from wedge-shaped components.

Main Results:

• Different detection techniques exhibit varying levels of measurement accuracy.
• Computational complexity differs significantly among the analyzed methods.
• Resistance to optical dispersion is a key differentiating factor for technique selection.

Conclusions:

• The choice of fringe center detection technique directly influences 3D inspection accuracy.
• Technique selection should balance computational cost, accuracy requirements, and expected optical dispersion.
• Understanding these trade-offs is essential for optimizing low-coherence interferometry applications.