Continuous measurement of optical surfaces using a line-scan interferometer with sinusoidal path length modulation

Area of Science:

• Optical Engineering
• Metrology

Background:

• Accurate measurement of optical surfaces is crucial for various applications.
• Existing methods may lack speed or continuous measurement capabilities for complex surfaces.

Purpose of the Study:

• To develop and demonstrate a fast, continuous measurement approach for rotationally symmetric optical surfaces.
• To validate the measurement and stitching concept using a five-axis system.

Main Methods:

• Utilized a line scanning interferometer with sinusoidal optical path length modulation.
• Employed a five-axis system with a high-precision rotational table for specimen and sensor positioning.
• Discussed the calibration procedures for the line sensor and the scanning/positioning system.

Main Results:

• Successfully demonstrated continuous measurement of optical surfaces.
• Presented proof-of-principle results for a rotational symmetric sinusoidal structure.
• Showcased measurements of a spherical lens with moderate slope, validating the stitching concept.

Conclusions:

• The presented approach offers a fast and effective method for continuous measurement of rotationally symmetric optical surfaces.
• The integration of a line scanning interferometer and a five-axis system provides high precision and flexibility.
• This technique is suitable for metrology applications requiring accurate characterization of optical components.